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Tabor Yimam A, Wassie GT, Alene GD. Postoperative trachomatous trichiasis and associated factors among adults who underwent trachomatous trichiasis surgery in Ambassel District, North-East Ethiopia. PLoS One 2024; 19:e0304407. [PMID: 38805451 PMCID: PMC11132444 DOI: 10.1371/journal.pone.0304407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 05/10/2024] [Indexed: 05/30/2024] Open
Abstract
BACKGROUND In Trachoma endemic countries, many people who underwent Trichiasis surgery faced a recurrence of the disease. Postoperative Trichiasis is a significant problem for patients and health care providers because it puts the eye at renewed risk of sight loss. Despite the low utilization of Trachomatous Trichiasis surgery and the high recurrence rate, evidence that elucidate why it recurs after surgery is limited. This study was aimed to assess the magnitude and associated factors of postoperative Trichiasis among 18 years and above individuals who underwent Trachomatous Trichiasis surgery between 2013 and 2019 in Ambassel District, Northeast Ethiopia, 2020. METHODS The community-based cross-sectional study design was conducted from March 10 to March 23/2020 in selected kebeles of Ambassel District. The required sample size (506) was calculated using EPI-INFO Version 7. A multi-stage sampling technique was used to employ study participants. Data were collected through the interviewer-administered structured pre-tested questionnaire and entered into EpiData version 3.1 and then exported to SPSS version 23.0 for analysis. Bi-variable and multivariable logistic regression models were fitted to identify associated factors of Postoperative Trachomatous Trichiasis. RESULTS Four hundred ninety two individuals participated in this study with a response rate of 97.2%. In Ambassel district, the prevalence of postoperative Trichiasis was 23.8% (95% CI = 19.9-27.8). Among associated factors of postoperative Trachomatous Trichiasis: age 50-59 (AOR = 3.34, CI = 1.38-8.1), 60-69 (AOR = 3.24, CI = 1.38-7.61), ≥70 years (AOR = 6.04, CI = 2.23-16.41), duration since surgery (AOR = 1.7, CI = 1.35-2.14), complication (AOR = 2.98, CI = 1.24-7.2), washing the face two times (AOR = 0.25, CI = 0.13-0.47), washing the face three and more times (AOR = 0.1, CI = 0.41-0.25), taking Azithromycin following surgery (AOR = 0.19, CI = 0.09-0.41), pre-operative epilation history (AOR = 2.11, CI = 1.14, 3.9) and having a knowledge about TrachomaTtrichiasis (AOR = 0.21, CI = 0.08-0.58) showed a statistical significant association. CONCLUSIONS The prevalence of postoperative Trichiasis in Ambassel District was higher than most Ethiopian studies. Age, frequency of face washing, medication following surgery, duration since the last surgery, knowledge about trachoma, pre-operative epilation history, and complication after surgery were identified to be independent factors. To minimize postoperative Trachomatous Trichiasis stakeholders need to consider health education for patients, provision of Azithromycin after surgery, and proper training for integrated eye care workers.
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Affiliation(s)
- Abdu Tabor Yimam
- Department of Epidemiology and Biostatistics, School of Public Health, Bahir Dar University, Bahir Dar, Ethiopia
| | - Gizachew Tadesse Wassie
- Department of Epidemiology and Biostatistics, School of Public Health, Bahir Dar University, Bahir Dar, Ethiopia
| | - Getu Degu Alene
- Department of Epidemiology and Biostatistics, School of Public Health, Bahir Dar University, Bahir Dar, Ethiopia
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Kreis AJ, Gower EW, Kropp M, Kello AB, Nouhoum G, Resnikoff S, Talero SL, Solomon AW. The prevention and management of postoperative trachomatous trichiasis: A systematic review. Surv Ophthalmol 2024; 69:93-102. [PMID: 36878359 DOI: 10.1016/j.survophthal.2023.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 02/24/2023] [Accepted: 02/27/2023] [Indexed: 03/07/2023]
Abstract
Among ocular infections, trachoma is the main cause of blindness. Repeated conjunctival Chlamydia trachomatis infections lead to trichiasis, corneal opacification, and visual impairment. Surgery is often needed to relieve discomfort and preserve vision; however, a high postoperative trachomatous trichiasis (PTT) rate has been observed in various settings. We wanted to know why, whether PTT rates could be reduced, and how to manage the PTT that occurs. We performed a search of the literature. Of 217 papers screened, 59 studies were identified for inclusion as potentially relevant, the majority having been excluded for not directly concerning PTT in humans. Preventing PTT is a major challenge. Only one published trial, the STAR trial in Ethiopia, has reported a cumulative PTT rate <10% one year after surgery. The literature on the management of PTT is sparse. Though no PTT management guidelines are available, high-quality surgery with a low rate of unfavorable outcomes for PTT patients is likely to require enhanced training of a smaller group of highly-skilled surgeons. Based on the surgical complexity and the authors' own experience, the pathway for patients suffering from PTT should be studied further for improvement.
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Affiliation(s)
- Andreas J Kreis
- Experimental Ophthalmology, University of Geneva, Geneva, Switzerland; Department of Ophthalmology, University Hospitals of Geneva, Geneva, Switzerland.
| | - Emily W Gower
- Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Martina Kropp
- Experimental Ophthalmology, University of Geneva, Geneva, Switzerland; Department of Ophthalmology, University Hospitals of Geneva, Geneva, Switzerland
| | - Amir B Kello
- World Health Organization Regional Office for Africa, Brazzaville, Congo
| | - Guirou Nouhoum
- Techniques and Technologies of Bamako, Institut d'Ophtalmologie Tropicale d'Afrique, University of the Sciences, Bamako, Mali
| | - Serge Resnikoff
- Organisation pour la Prévention de la Cécité, Paris, France; School of Optometry & Vision Science (SOVS), University of New South Wales, Sydney, Australia
| | - Sandra L Talero
- Research Department of Development and Innovation, Superior School of Ophthalmology, Barraquer Institute of America, Bogotá, Colombia
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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Sullivan KM, Harding-Esch EM, Batcho WE, Issifou AAB, Lopes MDFC, Szwarcwald CL, Vaz Ferreira Gomez D, Bougouma C, Christophe N, Kabore M, Bucumi V, Bella AL, Epee E, Yaya G, Trujillo-Trujillo J, Dejene M, Gebretsadik FS, Gebru G, Kebede F, Mathewos T, Cassama ETDS, Sanha S, Barasa E, Sultani HM, Watitu T, Tekeraoi R, Kalua KM, Masika MP, Traoré L, Minnih AO, Abdala M, Massangaie ME, Win Y, Apadinuwe SC, Mishra SK, Sharma S, Amza A, Kadri B, Nassirou B, Mpyet CD, Olobio N, Hussain A, Khan AA, Jambi G, Ko R, Kello AB, Badiane MD, Sarr B, Dalmar A, Elshafie BE, Kabona GE, Kaitaba O, Mwingira U, Simon A, Kanyi S, Awoussi MS, Togbey K, Baayenda G, Francis M, Tukahebwa EM, Bakhtiari A, Keil AP, Maselko J, Westreich D, Garae M, Taleo F, Al-Khateeb TQ, Mwale C, Solomon AW, Gower EW. Gender differences in the surgical management of trachomatous trichiasis: an exploratory analysis of global trachoma survey data, 2015-2019. Int Health 2023; 15:ii58-ii67. [PMID: 38048383 PMCID: PMC10695456 DOI: 10.1093/inthealth/ihad067] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 06/28/2023] [Accepted: 07/26/2023] [Indexed: 12/06/2023] Open
Abstract
BACKGROUND Trachomatous trichiasis (TT) is a painful, potentially blinding eye condition that can be managed through epilation or surgery. Women are affected by TT approximately twice as often as men and are believed to face gendered barriers to receiving surgical care to prevent vision loss. METHODS We used data from 817 cross-sectional surveys conducted during 2015-2019 in 20 African countries to estimate the prevalence difference (PD) between female and male eyes for four outcomes potentially indicating gender-related differences in TT management: (1) received surgery and developed postoperative TT (PTT), (2) never offered surgery, (3) offered surgery but declined it, and (4) offered epilation but never offered surgery. RESULTS The prevalence was modestly elevated among female eyes compared with male eyes for having PTT (PD:1.8 [95% confidence limits (CL): 0.6, 3.0]) and having declined surgery for the eye (PD: 6.2 [95% CL: 1.8, 10.7]). The proportion offered epilation was similar by gender (PD:0.5 [95% CL: -0.4, 1.3]), while never having been offered surgery was somewhat more prevalent among male eyes (PD: -2.1 [95% CL: -3.5, -0.7]). CONCLUSIONS Our results suggest potential gender differences in TT management. More research is needed to determine the causes and implications of the observed differences.
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Affiliation(s)
- Kristin M Sullivan
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Emma M Harding-Esch
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Wilfrid E Batcho
- Programme National De Lutte Contre Les Maladies Transmissibles, Ministère De La Santé, Cotonou, Benin
| | | | | | - Celia Landmann Szwarcwald
- Institute of Scientific and Technological Communication and Information in Health, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | | | - Clarisse Bougouma
- Direction de la Protection de la Santé de la Population, Ministère de la Santé, Burkina Faso
| | - Nassa Christophe
- Attaché de Santé en Épidémiologie, Programme National de Lutte Contre Les MTN, Burkina Faso
| | - Martin Kabore
- L'unité d'élimination du trachome, PNMTN, Ouagadougou, Burkina Faso
| | - Victor Bucumi
- Département En Charge des Maladies Tropicales, Négligées Ministère De La Santé Publique Et De La Lutte Contre Le Sida, Bujumbura, Burundi
| | - Assumpta L Bella
- Programme National de Lutte Contre La Cecite, Ministère de la Santé Publique, Yaoundé, Cameroun
| | - Emilienne Epee
- Department Of Ophthalmology, University of Yaoundé Yaounde Centre/Ministère de la Santé Publique, Yaoundé, Cameroun
| | - Georges Yaya
- Ministère de la Santé Publique, Bangui, Central African Republic
| | - Julian Trujillo-Trujillo
- Subdirectorate of Communicable Diseases, Ministry of Health and Social Protection, Bogotá, Colombia
| | | | - Fikre Seife Gebretsadik
- Neglected Tropical Disease Prevention and Control Program, Ministry of Health, Addis Ababa, Ethiopia
| | - Genet Gebru
- Neglected Tropical Disease Prevention and Control Program, Ministry of Health, Addis Ababa, Ethiopia
| | - Fikreab Kebede
- Neglected Tropical Disease Prevention and Control Program, Ministry of Health, Addis Ababa, Ethiopia
| | - Tsedeke Mathewos
- Neglected Tropical Disease Prevention and Control Program, Ministry of Health, Addis Ababa, Ethiopia
| | | | - Salimato Sanha
- Programa Nacional De Sau´de De Visão, Minsap, Bissau, Guinea-Bissau
| | | | | | | | | | - Khumbo M Kalua
- Blantyre Institute for Community Outreach, Blantyre, Malawi
| | - Michael P Masika
- Department of Clinical and Medical Rehabilitation Services, Ministry of Health, Lilongwe, Malawi
| | - Lamine Traoré
- National Eye Health Program, Ministry of Health and Social Development, Mali
| | - Abdallahi O Minnih
- Département Des Maladies Transmissibles, Ministère De La Santé Nouakchott, Nouakchott, Mauritania
| | - Mariamo Abdala
- Direção Nacional de Saúde Pública, Ministerio Da Saude, Maputo, Mozambique
| | | | - Ye Win
- Department of Public Health, Ministry of Health and Sports, Nay Pyi Taw, Myanmar
| | | | - Sailesh Kumar Mishra
- National Society for Comprehensive Eye Care, Nepal Netra Jyoti Sangh, Kathmandu, Nepal
| | | | - Abdou Amza
- Programme National De Santé Oculaire, Ministère De La Santé Publique, Niamey, Niger
| | - Boubacar Kadri
- Programme National De Santé Oculaire, Ministère De La Santé Publique, Niamey, Niger
| | - Beido Nassirou
- Programme National De Santé Oculaire, Ministère De La Santé Publique, Niamey, Niger
| | - Caleb D Mpyet
- Department of Ophthalmology, University of Jos, Jos, Plateau, Nigeria
| | - Nicholas Olobio
- Neglected Tropical Diseases Division, Department of Public Health, Federal Ministry of Health, Abuja, Nigeria
| | - Arif Hussain
- Community Ophthalmology, College of Ophthalmology & Allied Vision Sciences (COAVS), Mayo Hospital Lahore, Lahore, Pakistan
| | - Asad Aslam Khan
- College of Ophthalmology and Allied Vision Sciences, Mayo Hospital, Lahore, Pakistan
| | - Garap Jambi
- Prevention of Blindness Committee, PNG Eye Care, Boroko, Papua New Guinea
| | - Robert Ko
- National Department of Health, Waigani, Papua New Guinea
| | - Amir B Kello
- AF/UCU UHC/Communicable and Noncommunicable Diseases Unit, ESPEN, World Health Organization, Brazzaville, Republic of Congo
| | - Mouctar D Badiane
- Programme National de Promotion de La Santé Oculaire, Ministère de la Santé et de L'Action Sociale, Dakar, Senegal
| | - Boubacar Sarr
- Ministère de la Santé et de l'Action Sociale, Senegal
| | | | - Balgesa E Elshafie
- National Program for Prevention of Blindness, Federal Ministry of Health, Khartoum, Sudan
| | - George E Kabona
- Neglected Tropical Diseases Control Program, Ministry of Health, Dodoma, Tanzania
| | - Oscar Kaitaba
- Neglected Tropical Diseases Control Program, Ministry of Health, Dodoma, Tanzania
| | - Upendo Mwingira
- Neglected Tropical Diseases Control Program, Ministry of Health, Dodoma, Tanzania
| | - Alistidia Simon
- Neglected Tropical Diseases Control Program, Ministry of Health, Dodoma, Tanzania
| | - Sarjo Kanyi
- National Eye Health Programme, Ministry of Health and Social Welfare, Banjul, The Gambia
| | | | - Kwamy Togbey
- Programme National des Maladies Tropicales Negligées, Ministry of Health, Public Hygiene and Universal Access to Care, Lomé, Togo
| | - Gilbert Baayenda
- Neglected Tropical Diseases Control, Ministry of Health, Kampala, Uganda
| | - Mugume Francis
- Neglected Tropical Diseases Control, Ministry of Health, Kampala, Uganda
| | - Edridah M Tukahebwa
- Vector-Borne and Neglected Tropical Diseases, Ministry of Health, Kampala, Uganda
| | - Ana Bakhtiari
- International Trachoma Initiative, Task Force for Global Health, Decatur, Georgia, USA
| | - Alexander P Keil
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Joanna Maselko
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Daniel Westreich
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Mackline Garae
- Department of Neglected Tropical Diseases, Vanuatu Ministry of Health, Port Vila, Vanuatu
| | - Fasiah Taleo
- Department of Neglected Tropical Diseases, Vanuatu Ministry of Health, Port Vila, Vanuatu
| | | | - Consity Mwale
- Kitwe Teaching Eye Hospital, Ministry of Health, Kitwe, Zambia
| | - Anthony W Solomon
- Global Neglected Tropical Diseases Programme, World Health Organization, Geneva, Switzerland
| | - Emily W Gower
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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4
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Adimassu NF, Assem AS, Fekadu SA. Postoperative trachomatous trichiasis: a systematic review and meta-analysis study. Int Health 2023; 15:623-629. [PMID: 36852770 PMCID: PMC10629961 DOI: 10.1093/inthealth/ihad014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 01/04/2023] [Accepted: 02/10/2023] [Indexed: 03/01/2023] Open
Abstract
BACKGROUND Trachomatous trichiasis is the potential stage of trachoma in which the eyelashes scratch the surface of the globe, ultimately causing corneal opacity, visual impairment and blindness. The aim of this systematic review and meta-analysis is to obtain the pooled prevalence and associated factors of postoperative trachomatous trichiasis (PTT) in World Health Organization (WHO) trachoma-endemic regions. METHODS An inclusive literature search was undertaken using PubMed, Cochrane Library, Science Direct and Google Scholar databases from 30 May 2022 to 28 June 2022. I2 statistics and funnel plots were used to determine heterogeneity and publication bias among included studies. A random effects model was used to estimate pooled prevalence, incidence and odds ratios (ORs) with the respective 95% confidence intervals (CIs) using RevMan 5.4 software. RESULTS Eighteen articles were included in this meta-analysis and systematic review. The pooled prevalence of PTT was 19% (range 18-21). PTT was lower among young adults compared with old adults (OR 0.63 [95% CI 0.44 to 0.92]), single-dose oral azithromycin as compared with tetracycline eye ointment users (OR 0.82 [95% CI 0.69 to 0.99]) and minor trichiasis before surgery as compared with major trichiasis (OR 0.63 [95% CI 0.47 to 0.85]). CONCLUSIONS The incidence of PTT was higher than the WHO's recommendation. Prescribing single-dose oral azithromycin after surgery, periodic training for trichiasis surgeons, close follow-up and health education after surgery are crucial to minimize the recurrence.Study protocol registration on PROSPERO: CRD42022336003.
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Affiliation(s)
- Nebiyat Feleke Adimassu
- Department of Optometry, School of Medicine, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Abel Sinshaw Assem
- Department of Optometry, School of Medicine, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Sofonias Addis Fekadu
- Department of Optometry, School of Medicine, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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Simpson SJ, Higgins DP, Timms P, Mella VSA, Crowther MS, Fernandez CM, McArthur C, Phillips S, Krockenberger MB. Efficacy of a synthetic peptide Chlamydia pecorum major outer membrane protein vaccine in a wild koala (Phascolarctos cinereus) population. Sci Rep 2023; 13:15087. [PMID: 37699951 PMCID: PMC10497537 DOI: 10.1038/s41598-023-42296-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 09/07/2023] [Indexed: 09/14/2023] Open
Abstract
Chlamydiosis is a significant disease affecting Eastern Australian koala (Phascolarctos cinereus) populations, impacting individual animal welfare and fecundity and therefore influencing population dynamics. The aim of this study was to investigate the effect of a synthetic peptide vaccine based on 4 components of the Chlamydia pecorum major outer membrane protein (MOMP), over an 18-month period in a koala population severely impacted by chlamydiosis. Wild koalas were recruited into a vaccination or a placebo treatment group on a random allocation, then followed through a period of 18 months, with recapture at 6 monthly intervals. Vaccination did not alter clinical disease expression or chlamydial shedding from the ocular or urogenital sites. Vaccination did not stimulate a significant plasma anti-MOMP IgG response, when compared to the placebo group. There was no significant effect of vaccination on IFN-γ and IL-17A mRNA expression of peripheral blood lymphocytes when stimulated with rMOMP. We have demonstrated that a synthetic peptide vaccination against chlamydiosis is not an effective management tool in a koala population with a high prevalence of C. pecorum infection and related disease. The lack of antigenic response found in this study suggests that further research utilising a larger, full-length antigen is an avenue worth investigation if we are to consider vaccination as a part of a management strategy in diseased koala populations.
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Affiliation(s)
- Sarah J Simpson
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, 2006, Australia.
| | - Damien P Higgins
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Peter Timms
- Centre for Bioinnovation, University of the Sunshine Coast, Sippy Downs, QLD, 4556, Australia
| | - Valentina S A Mella
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Mathew S Crowther
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Cristina M Fernandez
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Clare McArthur
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Samuel Phillips
- Centre for Bioinnovation, University of the Sunshine Coast, Sippy Downs, QLD, 4556, Australia
| | - Mark B Krockenberger
- Sydney School of Veterinary Science, The University of Sydney, Sydney, NSW, 2006, Australia
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Gower EW, Kello AB, Kollmann KHM, Merbs SL, Sisay A, Tadesse D, Alemayehu W, Pedlingham N, Dykstra RS, Johnson JE. The impact of incorporating surgical simulation into trichiasis surgery training on operative aspects of initial live-training surgeries. PLoS Negl Trop Dis 2023; 17:e0011125. [PMID: 37014903 PMCID: PMC10112793 DOI: 10.1371/journal.pntd.0011125] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 04/18/2023] [Accepted: 01/30/2023] [Indexed: 04/05/2023] Open
Abstract
BACKGROUND While surgical simulation is regularly used in surgical training in high-income country settings, it is uncommon in low- and middle-income countries, particularly for surgical training that primarily occurs in rural areas. We designed and evaluated a novel surgical simulator for improving trachomatous trichiasis (TT) surgery training, given that trichiasis is mostly found among the poorest individuals in rural areas. METHODOLOGY/PRINCIPAL FINDINGS TT surgery programs were invited to incorporate surgical simulation with a new, high fidelity, low-cost simulator into their training. Trainees completed standard TT-surgery training following World Health Organization guidelines. A subset of trainees received three hours of supplemental training with the simulator between classroom and live-surgery training. We recorded the time required to complete each surgery and the number of times the trainer intervened to correct surgical steps. Participants completed questionnaires regarding their perceptions. We also assessed trainer and trainee perceptions of surgical simulation training as part of trichiasis surgery training. 22 surgeons completed standard training and 26 completed standard training plus simulation. We observed 1,394 live-training surgeries. Average time to first live-training surgery completion was nearly 20% shorter the simulation versus the standard group (28.3 vs 34.4 minutes; p = 0.02). Trainers intervened significantly fewer times during initial live-training surgeries in the simulation group (2.7 vs. 4.8; p = 0.005). All trainers indicated the simulator significantly improved training by allowing trainees to practice safely and to identify problem areas before performing live-training surgeries. Trainees reported that simulation practice improved their confidence and skills prior to performing live-training surgeries. CONCLUSIONS A single high-fidelity surgical simulation session can significantly improve critical aspects of initial TT surgeries.
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Affiliation(s)
- Emily W. Gower
- Departments of Epidemiology and Ophthalmology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Amir B. Kello
- World Health Organization, Regional Office for Africa, Brazzaville, Republic of Congo
| | | | - Shannath L. Merbs
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | | | | | | | | | - Richard S. Dykstra
- Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
| | - James E. Johnson
- Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
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Abstract
Trachoma is a neglected tropical disease caused by infection with conjunctival strains of Chlamydia trachomatis. It can result in blindness. Pathophysiologically, trachoma is a disease complex composed of two linked chronic processes: a recurrent, generally subclinical infectious-inflammatory disease that mostly affects children, and a non-communicable, cicatricial and, owing to trichiasis, eventually blinding disease that supervenes in some individuals later in life. At least 150 infection episodes over an individual's lifetime are needed to precipitate trichiasis; thus, opportunity exists for a just global health system to intervene to prevent trachomatous blindness. Trachoma is found at highest prevalence in the poorest communities of low-income countries, particularly in sub-Saharan Africa; in June 2021, 1.8 million people worldwide were going blind from the disease. Blindness attributable to trachoma can appear in communities many years after conjunctival C. trachomatis transmission has waned or ceased; therefore, the two linked disease processes require distinct clinical and public health responses. Surgery is offered to individuals with trichiasis and antibiotic mass drug administration and interventions to stimulate facial cleanliness and environmental improvement are designed to reduce infection prevalence and transmission. Together, these interventions comprise the SAFE strategy, which is achieving considerable success. Although much work remains, a continuing public health problem from trachoma in the year 2030 will be difficult for the world to excuse.
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Shrestha R, Merbs SL, Bayissasse B, Sisay A, Beckwith C, Courtright P, Gower EW. Characteristics and perspectives of patients with postoperative trichiasis in Hadiya Zone, Ethiopia. Int Health 2022; 14:i49-i56. [PMID: 35385867 PMCID: PMC8986352 DOI: 10.1093/inthealth/ihac004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 12/08/2021] [Accepted: 01/25/2022] [Indexed: 11/17/2022] Open
Abstract
Background Postoperative trachomatous trichiasis (PTT) is a challenge for trichiasis surgery programs. Little is known about PTT patients’ perceptions regarding outcomes and future disease management. This study aimed to understand the characteristics of PTT patients, how they managed trichiasis and their perceptions of prior surgeries and future surgery uptake. Methods Patients with PTT were identified during an existing trichiasis screening program in Hadiya Zone, Ethiopia. A vision assessment and evaluation of the eyelids were conducted to determine distance vision, presence and severity of trichiasis and eyelid contour abnormalities. A questionnaire was administered to obtain information regarding patients’ perceptions of surgery and PTT management approaches. Descriptive statistics were used to characterize PTT and determine associations between PTT severity and patient perceptions. Results Among 404 participants, most were female (79.7%) and aged 40–60 y (62.6%). In total, 514 eyelids had PTT, and nearly half had severe PTT (46.9%). Although >50% of participants were currently epilating to manage their PTT, the majority (82.8%) indicated that they wanted repeat surgery. Most participants indicated that pain persisted despite epilation. The majority (75.1%) indicated satisfaction with their prior surgery and 59.6% indicated that they would recommend surgery to others. Conclusions This study, which included a large proportion of severe PTT cases, indicated that individuals were generally satisfied with prior surgery and would prefer to have surgery again for PTT management.
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Affiliation(s)
- Riju Shrestha
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Shannath L Merbs
- Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | | | | | - Paul Courtright
- Sightsavers, Haywards Heath, UK.,Kilimanjaro Centre for Community Ophthalmology, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa
| | - Emily W Gower
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.,Department of Ophthalmology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
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9
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Effect of repeated epilation for minor trachomatous trichiasis on lash burden, phenotype and surgical management willingness: A cohort study. PLoS Negl Trop Dis 2020; 14:e0008882. [PMID: 33315876 PMCID: PMC7769600 DOI: 10.1371/journal.pntd.0008882] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 12/28/2020] [Accepted: 10/12/2020] [Indexed: 11/19/2022] Open
Abstract
Background WHO endorsed the use of epilation as an alternative treatment to surgery for the management of both minor unoperated TT (UTT) and postoperative TT (PTT). However, some trachoma control programmes hesitated to implement epilation citing concerns that it would hamper TT surgical acceptance and result in larger numbers of and stiffer trichiatic eyelashes than the original TT lashes. We investigated the burden and phenotypes of post-epilation trichiatic eyelashes, and willingness to accept surgical management separately in unoperated and postoperative TT cases. Methodology/Principal findings We recruited cases with minor (≤5 eyelashes from the upper eyelid touching the eye or evidence of epilation in <1/3rd of the upper eyelid) UTT (170) and PTT (169) from community-based screenings in Amhara Region, Ethiopia. Participants eyes were examined and data on present and future willingness to accept surgical management collected at baseline and every month for 6-months. Eyelashes touching the eye were counted and their phenotypes documented. Participants were trained on how to epilate. Epilation was done by the participants at home and by the examiner during follow-ups when requested by the participant. Follow-up rates were ≥97%. There was evidence of a significant reduction in the burden of trichiatic eyelashes in unoperated (mean difference = -0.90 [-1.11– -0.69]; RR = 0.50 [95% CI, 0.40–0.62]; p<0.0001), and postoperative (mean difference = -1.16 [-1.36– -0.95]; RR = 0.38 [95% CI, 0.31–0.48]; p<0.0001) cases 6-month after frequent epilation. Post-epilation trichiatic eyelashes at 6-months had higher odds of being thin (40.2% vs 55.8%, OR = 1.88 [95% CI, 1.21–2.93]; p = 0.0048), weak (39.8% vs 70.8%, OR = 3.68 [95%CI,2.30–5.88]; p<0.0001), and half-length (30.9% vs 43.3%, OR = 1.71 [1.09–2.68]; p = 0.020) than the pre-epilation trichiatic eyelashes in unoperated cases. There was a significant increase in the proportion of weak trichiatic eyelashes (OR = 1.99 [95% CI, 1.03–3.83; p = 0.039) in postoperative cases. In all 6 follow-up time points, 120/164 (73.2%) of unoperated and 134/163 (82.2%) of postoperative cases indicated that they would accept surgery if their trichiasis progressed. Conclusions/Significance In this study setting, frequent epilation neither hampers surgical acceptance nor results in more damaging trichiatic eyelashes than the pre-epilation lashes; and can be used as an alternative to the programmatic management of minor unoperated and postoperative TT cases. Trachomatous Trichiasis (TT), the blinding stage of trachoma, ranges from few peripheral eyelashes touching the eye to all eyelashes scratching the cornea. TT is mainly treated with corrective eyelid surgery. However, not all TT cases require surgical correction, and some, particularly, those with few eyelashes decline surgery. Epilation, the repeated removal of eyelashes, is a very common clinical and traditional practice in many trachoma endemic settings. The World Health Organisation recommends that epilation can be offered as an alternative management strategy to surgery for patients with few eyelashes touching the eye or refusing surgery. However, some trachoma control programmes hesitated to implement epilation with the concern that it would hamper surgical acceptance and results in larger numbers of and stiffer eyelashes touching the eye than the original TT eyelashes. In this study, we explored if these concerns are true in epilating minor (≤5 eyelashes from the upper eyelid touching the eye or evidence of epilation in <1/3rd of the upper eyelid) unoperated (170) and postoperative TT (169) cases. We found, in the contrary to these concerns, the post-epilation eyelashes touching the eye were less damaging being fewer in number, thinner, weaker and shorter than the pre-epilation eyelashes. In addition, the majority of both unoperated and postoperative cases indicated that they are willing to accept surgery if their trichiasis progressed.
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Mwangi G, Courtright P, Solomon AW. Systematic review of the incidence of post-operative trichiasis in Africa. BMC Ophthalmol 2020; 20:451. [PMID: 33203380 PMCID: PMC7670604 DOI: 10.1186/s12886-020-01564-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 07/10/2020] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Surgery for trichiasis is one of the pillars of the World Health Organization's strategy for global elimination of trachoma as a public health problem. A high incidence of post-operative trichiasis or other poor surgical outcomes could jeopardize these efforts. In this review, we aimed to summarize the reported incidence of post-operative trichiasis and other poor outcomes of trichiasis surgery in Africa. METHODS We conducted a systematic literature search using PubMed, Academic Search Premier, Africa-Wide Information, CINAHL and Health Source Nursing through EBSCOhost, Web of Science, and the Cochrane Central Register of Controlled Trials. Reference lists of included studies were also reviewed to identify further potentially relevant publications. All observational and interventional studies that measured post-operative trichiasis in Africa as an outcome of trichiasis surgery were included. RESULTS Thirty-five papers reporting on 22 studies (9 interventional,13 observational; total 13,737 participants) met the inclusion criteria. The reported incidence of post-operative trichiasis in the included studies ranged from 2% (at 6 weeks after bilamellar tarsal rotation) to 69% (at 3 weeks after anterior lamellar repositioning). The incidence varied by surgical procedure, study design, and length of follow-up. CONCLUSION Trichiasis surgical outcomes should be improved. National trachoma programmes could benefit from identifying and adopting strategies to improve the performance and quality of their surgical service.
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Affiliation(s)
- Grace Mwangi
- Department of Surgery, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa.
| | - Paul Courtright
- Kilimanjaro Centre for Community Ophthalmology, Division of Ophthalmology, University of Cape Town, Cape Town, South Africa
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
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Djore D, Djibrine D, Ali AB, Tyau-Tyau H, Hiron D, Kali B, Biao JE, Bernasconi J, Bengraïne K, Resnikoff S. Pilot Audit of Trichiasis Surgery Outcomes Using a Mobile App in the Republic of Chad. Middle East Afr J Ophthalmol 2020; 27:14-21. [PMID: 32549719 PMCID: PMC7276166 DOI: 10.4103/meajo.meajo_75_19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 10/06/2019] [Accepted: 02/18/2020] [Indexed: 11/10/2022] Open
Abstract
PURPOSE: The purpose of the study was to assess the feasibility of a mobile data collection app for use in trichiasis surgical audits in the Melfi and Mangalme districts of the Guera region of the Republic of Chad and to perform a cost analysis to determine if the auditing mechanism could be implemented nationally. MATERIALS AND METHODS: Patients who underwent trichiasis surgery 6 months prior and who had follow-up 7–14 days after surgery were included in the study. Each surgeon had a sample of 20% of operated eyelids; nine surgeons with data for ≥20 eyelids were included. A trichiasis recurrence rate of ≥25% suggested that the surgeon needed retraining. Smartphones captured data using the data collection app, which transmitted data to an online server. Direct costs and supervision costs were collated and summed. RESULTS: There were 916 eyelids operated on; 170 patients (269 eyelids, 29% follow-up rate) participated in the audit. Twenty participants (11.8%) had recurrence. The mean recurrence rate among surgeons was 8.3% (standard deviation: 0.07%; range: 0%–17.9%). None had a recurrence rate of ≥25%; thus, no retraining was necessary. The total cost of the audit was US$15,111.25 ($12,882.28 in direct costs and $2,228.97 in supervision costs). CONCLUSIONS: The simple, easy-to-use, and low-cost mobile auditing mechanism is a practical solution for conducting surgical audits in remote and resource-limited settings and is undergoing national scale-up by the Chadian trachoma elimination program.
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Affiliation(s)
| | - Djada Djibrine
- Faculty of Medicine of N'Djamena, N'Djamena, Chad.,Department of Ophtalmology, National Referral Hospital, N'Djamena, Chad
| | | | | | - Doniphan Hiron
- Organization for the Prevention of Blindness, Paris, France
| | - Barka Kali
- Organization for the Prevention of Blindness, N'Djamena, Chad
| | - Jean-Eudes Biao
- Organization for the Prevention of Blindness, N'Djamena, Chad
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12
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West SK. Milestones in the fight to eliminate trachoma. Ophthalmic Physiol Opt 2020; 40:66-74. [PMID: 32017172 DOI: 10.1111/opo.12666] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 12/20/2019] [Indexed: 11/29/2022]
Abstract
PURPOSE Trachoma, a chronic conjunctivitis that can result in vision loss from trichiasis, is targeted for global elimination by 2020. Several milestones in the long process towards elimination are noteworthy for the impact they have had on changing or accelerating progress. The purpose of this review is to describe the milestones and the impact they have had both for trachoma elimination and beyond. FINDINGS Eight milestones are presented. They are discovery of the causative agent; development of a clinical grading scheme; establishment of the World Health Organization Alliance for the Global Elimination of Trachoma by 2020; setting targets that define elimination; building an evidence base for trichiasis surgery; azithromycin donation programme; use of the SAFE strategy (Surgery, Antibiotics, Facial cleanliness, and Environmental improvement); and The Global Trachoma Mapping Project. SUMMARY These milestones have significantly pushed the progress towards elimination. Despite challenges to achieving the goal of elimination by 2020, there is continued commitment into the future to ensure that this preventable cause of blindness is no longer a threat.
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Affiliation(s)
- Sheila K West
- Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins Medicine, Baltimore, USA
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13
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Elbaklish KH, Saleh SM, Gomaa WA. Lamellar Tarsectomy Procedure In Major Trichiasis Of The Upper Lid. Clin Ophthalmol 2019; 13:2251-2259. [PMID: 31819349 PMCID: PMC6877448 DOI: 10.2147/opth.s210038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 10/15/2019] [Indexed: 11/30/2022] Open
Abstract
Aims Evaluation of failure rate and outcomes between skin and muscle surgery and lamellar tarsectomy procedure in major trichiasis of the upper lid. Design Quasi-randomized clinical study. Methods and subjects One hundred individuals with major trichiasis of the upper lid were enrolled and assigned to either skin and muscle surgery (group A) or a lamellar tarsectomy procedure (group B). Participants were examined at 6 and 12 months. The primary outcome measure (failure rate) was the percentage of participants having five or more eyelashes touching the globe or having surgery performed at any follow-up time in both groups. The secondary outcomes included failure time and changes in both visual acuity and corneal opacity. Results Risk failure over 6 months was 40% in group A and 10% in group B. Absolute risk reduction was 30% (95% CI=14.08–45.92%). Cumulative risk failure over 12 months was 20% in group A and 0.00% in group B after the second intervention. Absolute risk reduction was 20% (95% CI=8.58–31.42%). The number needed to treat (NNT) was 3.3 patients (95% CI=2.2–7.1). The mean number of rubbing lashes was greater in the skin and muscle group than in the lamellar tarsectomy group for 6 and 12 month examinations (0.002, 0.005). The change in visual acuity between the two groups was not significant. Recurrent trichiasis was noticed earlier, 6 weeks after surgery, in the skin and muscle group participants, and later, 3 months after surgery, in the lamellar tarsectomy group participants. Conclusion The lamellar tarsectomy procedure is a good choice for management of major trichiasis of the upper lid. The subjective symptoms and lid margin conjunctivalization were improved in lamellar tarsectomy participants. Absence of new corneal opacity or a change in existing corneal opacification was noticed at the 12 months follow-up study.
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Affiliation(s)
| | - Safaa M Saleh
- Ophthalmology Department, Ain Shams University, Cairo, Egypt
| | - Wael Adel Gomaa
- Ophthalmology Department, Ain Shams University, Cairo, Egypt
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Habtamu E, Wondie T, Tadesse Z, Atinafu B, Gashaw B, Gebeyehu A, Kelly Callahan E, Macleod D, Burton MJ. Posterior lamellar versus bilamellar tarsal rotation surgery for trachomatous trichiasis: Long-term outcomes from a randomised controlled trial. EClinicalMedicine 2019; 17:100202. [PMID: 31891136 PMCID: PMC6933225 DOI: 10.1016/j.eclinm.2019.10.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 10/14/2019] [Accepted: 10/21/2019] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND We re-examined the participants of a clinical trial four years after enrolment to identify which of the two most commonly used eyelid surgery procedures to treat the blinding stage of trachoma (trachomatous trichiasis, TT), the posterior Lamellar Tarsal Rotation (PLTR) and Billamelar Tarsal Rotation (BLTR), gives better results in the long-term. METHODS A randomised, controlled, single masked clinical trial was done in Ethiopia. At baseline, adults (aged >18 years with upper lid unoperated TT were recruited from a community-based screening. Participants were randomly assigned (1:1), to either BLTR or PLTR surgery, stratified by surgeon. At 4 years an independent assessor masked to allocation examined the trial participants' eyes using the same procedures as for the baseline and earlier follow-ups. The primary outcome was the proportion of individuals who had recurrence (postoperative TT, PTT) at the 4-year examination, or a history of repeat surgery in the 4-year period. The intervention effect was estimated by logistic regression, controlled for surgeon as a fixed effect in the model. The trial is registered with the Pan African Clinical Trials Registry (number PACTR201401000743135). FINDINGS 1000 participants with TT were enrolled, randomly assigned, and treated (501 in the BLTR group and 499 in the PLTR group) between Feb 13, 2014, and May 31, 2014. At year 4, 943 (94.3%) participants were re-examined (471, PLTR; 472, BLTR) and included in the primary outcome analysis. PTT had developed in 169/943 (17•9%) study eyes, among which 129 (76•3%) had minor trichiasis (≤5 lashes touching the eye). PTT was significantly more frequent at 4-year in the BLTR arm (105/472 [22•2%]) than the PLTR arm (64/471 [13•6%]), adjusted OR 1•82 (95% CI, 1•29-2•56); p = 0•0006, with 8•6% (95%CI 3•8-13•5) risk difference. INTERPRETATION The PLTR surgical procedure had superior long-term outcomes to the BLTR with significantly lower risk of PTT supporting the current WHO guideline that the PLTR should be the procedure of choice for training new surgeons in the programmatic management of TT.
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Affiliation(s)
- Esmael Habtamu
- International Centre for Eye Health, Department of Clinical Research, London School of Hygiene & Tropical Medicine, London, UK
- The Carter Center, Addis Ababa, Ethiopia
| | | | | | | | | | | | | | - David Macleod
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Matthew J. Burton
- International Centre for Eye Health, Department of Clinical Research, London School of Hygiene & Tropical Medicine, London, UK
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Pre-operative trichiatic eyelash pattern predicts post-operative trachomatous trichiasis. PLoS Negl Trop Dis 2019; 13:e0007637. [PMID: 31589610 PMCID: PMC6797216 DOI: 10.1371/journal.pntd.0007637] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 10/17/2019] [Accepted: 07/17/2019] [Indexed: 11/19/2022] Open
Abstract
IMPORTANCE Trichiasis surgery programs globally have faced high rates of poor surgical outcomes. Identifying correctable risk factors for improving long-term outcomes is essential for countries targeting elimination of trachoma as a public health problem. OBJECTIVE To determine whether the location of trichiatic eyelashes prior to surgery influences development of post-operative trichiasis (PTT) within two years after surgery. DESIGN Secondary data analysis of four randomized clinical trials evaluating methods to improve trichiasis surgery outcomes. These include the Surgery for Trichiasis, Antibiotics for Recurrence (STAR) trial, Partnership for Rapid Elimination of Trachoma (PRET-Surgery), absorbable versus silk sutures trial, and epilation versus surgery for minor trichiasis trial. SETTING Primary trials were conducted in rural areas of Ethiopia and Tanzania. INTERVENTIONS OR EXPOSURES Trichiasis surgery performed with either the bilamellar tarsal rotation procedure or posterior lamellar rotation procedure. MAIN OUTCOMES Prevalence of PTT within two years after surgery, location of trichiatic eyelashes pre-operatively and post-operatively. RESULTS 6,747 eyelids that underwent first-time trichiasis surgery were included. PTT rates varied by study, ranging from 10-40%. PTT was less severe (based on number of trichiatic eyelashes) than initial trichiasis for 72% of those developing PTT, and only 2% of eyelids were worse at follow up than pre-operatively. Eyelids with central only-trichiasis pre-operatively had lower rates of PTT than eyelids with peripheral only trichiasis in each of the three trials that included severe TT cases. 10% of eyelids with peripheral trichiasis pre-operatively that develop PTT have central TT post-operatively. CONCLUSIONS AND RELEVANCE Pre-operative central trichiasis is less likely than peripheral trichiasis to be associated with subsequent PTT. Regardless of type of surgery, surgeon skill levels, or pre-operative trichiasis severity, the presence of peripheral trichiasis pre-operatively is associated with higher rates of PTT. Making an incision that extends the length of the eyelid and adequately rotating the nasal and temporal aspects of the eyelid when suturing may help to minimize the chance of developing peripheral PTT. TRIAL REGISTRATION ClinicalTrials.gov PRET: NCT00886015; Suture: NCT005228560; Epilation: NCT00522912.
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Ramadhani AM, Derrick T, Macleod D, Massae P, Mafuru E, Malisa A, Mbuya K, Roberts CH, Makupa W, Mtuy T, Bailey RL, Mabey DCW, Holland MJ, Burton MJ. Progression of scarring trachoma in Tanzanian children: A four-year cohort study. PLoS Negl Trop Dis 2019; 13:e0007638. [PMID: 31412025 PMCID: PMC6709924 DOI: 10.1371/journal.pntd.0007638] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 08/26/2019] [Accepted: 07/17/2019] [Indexed: 11/18/2022] Open
Abstract
Background Trachoma is a progressive blinding disease initiated by infection of the conjunctiva with Chlamydia trachomatis. Repeated infections are thought to cause chronic inflammation, which drives scarring, leading to in-turning of the eyelids. The relationship between C. trachomatis, clinical inflammation and scarring development in children is not fully understood due to a paucity of longitudinal studies with infection data at frequent follow-up. Methods and findings This longitudinal cohort study took place in northern Tanzania. Children aged 6–10 years at baseline were eligible for inclusion. Participants were visited every three months for four years. Clinical signs and conjunctival swabs for C. trachomatis detection by qPCR were collected at each time-point. Conjunctival photographs from baseline and final time-points were graded and compared side-by-side to determine scarring incidence and progression. Of the 666 children enrolled in the study, outcome data were obtained for 448. Scarring progression was detected in 103/448 (23%) children; 48 (11%) of which had incident scarring and 55 (12%) had progression of existing scarring. Scarring was strongly associated with increasing episodes of trachomatous papillary inflammation (TP). Weaker associations were found between episodes of C. trachomatis infection and follicular trachoma (TF) with scarring progression in unadjusted models, which were absent in multivariable analysis after adjusting for inflammation (multivariable results: C. trachomatis p = 0.44, TF p = 0.25, TP p = <0.0001, age p = 0.13, female sex p = 0.05). Individuals having TP at 30% or more of the time-points they were seen had an odds ratio of 7.5 (95%CI = 2.7–20.8) for scarring progression relative to individuals without any TP detected during the study period. Conclusions These data suggest that the effect of infection on scarring progression is mediated through papillary inflammation, and that other factors contributing to the development of inflammation, in addition to C. trachomatis infection, may be important in driving conjunctival scarring progression in children. The addition of TP as a measure in trachoma control programs would provide an indication of the future risk of developing scarring sequelae. Trachoma is the leading cause of preventable blindness worldwide and is targeted for elimination as a public health problem by 2020. The natural history of trachoma is not completely understood however. We conducted a four-year longitudinal study in a trachoma-endemic area of northern Tanzania with detailed follow up every three months. In the four-year study period, nearly one quarter of children developed progression of conjunctival scarring, despite three rounds of annual mass drug administration (MDA) for trachoma control. Disease progression was strongly associated with increasing proportion of episodes with conjunctival papillary inflammation (TP), and only weakly associated with Chlamydia trachomatis infection and trachomatous inflammation–follicular (TF). Analysis revealed that associations between infection and TF with scarring progression were mediated through TP, and that other factors causing individual differences in TP were also contributing to scarring progression. These data have significant implications for trachoma control. We hypothesise that in individuals who have previously experienced ocular C. trachomatis infection, TP is the primary driver of scarring progression. The addition of TP to trachoma surveillance programs would provide an indicator for active disease progression in the community and a more accurate guide to the need for future trichiasis interventions.
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Affiliation(s)
- Athumani M. Ramadhani
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- * E-mail:
| | - Tamsyn Derrick
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - David Macleod
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Elias Mafuru
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Aiweda Malisa
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Kelvin Mbuya
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | | | | | - Tara Mtuy
- London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Robin L. Bailey
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David C. W. Mabey
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin J. Holland
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- London School of Hygiene and Tropical Medicine, London, United Kingdom
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Hu VH, Macleod D, Massae P, Afwamba I, Weiss HA, Mabey DCW, Bailey RL, Burton MJ. Non-Chlamydial Bacterial Infection and Progression of Conjunctival Scarring in Trachoma. Invest Ophthalmol Vis Sci 2019; 59:2339-2344. [PMID: 29847638 PMCID: PMC5939686 DOI: 10.1167/iovs.17-23381] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Purpose The purpose of this study was to assess whether non-chlamydial bacterial infection is associated with progression of trachomatous scarring in adults. Methods This was a cohort study involving 800 participants in northern Tanzania who underwent clinical examination, photography, and conjunctival swab collection for microbiology over a 24-month period. Samples for microbiology were inoculated onto blood and chocolate agar, and Chlamydia trachomatis was detected by PCR. Progression was determined by comparison of baseline to 24-month photographs. Results C. trachomatis was detected in only four participants at baseline. At 24 months, 617 participants (77.1%) were followed up. Of those seen at 24 months, 452 could be reliably assessed. Definite scarring progression (progressors) was seen in 345 (55.9%); there was no progression (nonprogressors) in 107 (17.3%). Using combined baseline and 12-month microbiology results, progressors had significantly higher levels of commensal and pathogenic bacterial organisms detected compared with nonprogressors. After adjusting for age, baseline scarring, and ethnicity, there was weak evidence (P = 0.07) that the bacteria category was associated with scarring progression (commensal organisms only: odds ratio [OR] = 1.61; 95% confidence interval [CI]: 0.90 to 2.89; pathogenic organisms either with or without commensal: OR = 2.39; 95% CI: 1.10 to 5.16). Conclusion The findings were consistent with the possibility that trachomatous scarring in adults is associated with the presence of non-chlamydial bacterial organisms, particularly pathogenic organisms. C. trachomatis was detected very infrequently and may not be an important factor in the pathogenesis of scarring progression in adults. This has implications for trachoma control programs, which largely concentrate on reducing C. trachomatis levels and transmission.
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Affiliation(s)
- Victor H Hu
- London School of Hygiene and Tropical Medicine, London, United Kingdom.,Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - David Macleod
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Isaac Afwamba
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Helen A Weiss
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David C W Mabey
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Robin L Bailey
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew J Burton
- London School of Hygiene and Tropical Medicine, London, United Kingdom.,Kilimanjaro Christian Medical Centre, Moshi, Tanzania
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Fluorometholone 0.1% as Ancillary Therapy for Trachomatous Trichiasis Surgery: Randomized Clinical Trial. Am J Ophthalmol 2019; 197:145-155. [PMID: 30267699 DOI: 10.1016/j.ajo.2018.09.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/12/2018] [Accepted: 09/17/2018] [Indexed: 01/30/2023]
Abstract
PURPOSE To assess the hypothesis that fluorometholone 0.1% eye drops are safe and effective as adjunctive therapy for trachomatous trichiasis (TT) surgery; determining the most promising dose. DESIGN Randomized, placebo-controlled, double-masked parallel dose-ranging clinical trial. METHODS Patients undergoing upper lid TT surgery at a rural Ethiopian hospital were randomized to fluorometholone 0.1% twice daily for 4 weeks, 4 times daily for 4 weeks, 4 times daily for 8 weeks, or matching frequency placebo in a 3:1:3:1:3:1 ratio for 1 eye. Randomization was stratified by TT severity (1-4 vs ≥5 lashes touching the globe). Safety outcomes (intraocular pressure [IOP] elevation, cataract, and other dose-limiting toxicities) and postoperative TT incidence were assessed over 1 year. RESULTS Subjects randomized were 39:13:39:13:38:13 in the respective groups, and 1 subject in the 8-weeks fluorometholone group was withdrawn. Of 154 subjects, 148 (96.1%) completed 1 year's follow-up. Among 76 eyes receiving fluorometholone 4 times daily, 1 developed IOP elevation ≥ 30 mm Hg (to 37 mm Hg) and 1 had an allergic reaction attributed to the study drug; each resolved upon drug cessation without sequelae. No cataract or other dose-limiting toxicity events occurred. Postoperative TT within 1 year occurred in 29.3% of placebo eyes vs 17.7%, 19.6%, and 23.2% among the respective fluorometholone groups (P = .29 comparing placebo vs all active treatments combined). CONCLUSIONS The results suggest fluorometholone 0.1% is likely to be safe and efficacious to reduce postoperative TT following TT surgery, and 1 drop twice daily for 4 weeks is the most promising dose. Confirmation in a full-scale clinical trial is needed before programmatic implementation.
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Tian L, Wang NL. Trachoma control: the SAFE strategy. Int J Ophthalmol 2018; 11:1887-1888. [PMID: 30588417 DOI: 10.18240/ijo.2018.12.01] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 11/20/2018] [Indexed: 11/23/2022] Open
Abstract
As a contagious bacterial infection that affects the conjunctival covering of the eye, the cornea and the eyelids, trachoma is controlled by an endorsed integrated strategy consisting of surgery for trichiasis, antibiotic therapy, facial cleanliness and environmental improvement, namely, the SAFE strategy developed by World Health Organization. Developed based on evidence from previous field trials and constantly modified in practice, SAFE strategy has greatly boosted the progress in trachoma control. Regardless of the fact that there are still many pending questions, national program coordinators are convinced that trachoma control initiative based on SAFE strategy would be effective.
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Affiliation(s)
- Lei Tian
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Vision Science Key Lab, Beijing 100730, China
| | - Ning-Li Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Vision Science Key Lab, Beijing 100730, China
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Habtamu E, Wondie T, Aweke S, Tadesse Z, Zerihun M, Gashaw B, Roberts CH, Kello AB, Mabey DCW, Rajak SN, Callahan EK, Macleod D, Weiss HA, Burton MJ. Oral doxycycline for the prevention of postoperative trachomatous trichiasis in Ethiopia: a randomised, double-blind, placebo-controlled trial. Lancet Glob Health 2018; 6:e579-e592. [PMID: 29653629 PMCID: PMC5912946 DOI: 10.1016/s2214-109x(18)30111-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 02/11/2018] [Accepted: 02/22/2018] [Indexed: 01/22/2023]
Abstract
BACKGROUND Trachomatous trichiasis is treated surgically to prevent sight loss. Unfavourable surgical outcomes remain a major challenge. We investigated the hypothesis that doxycycline might reduce the risk of postoperative trichiasis following surgery in patients with trachomatous trichiasis through anti-matrix metalloproteinase and anti-inflammatory activity. METHODS In this randomised, double-blind, placebo-controlled trial, adults (aged >18 years) with upper lid trachomatous trichiasis in association with tarsal conjunctive scarring were recruited through community-based screening and surgical outreach campaigns in Ethiopia. Individuals who had previously had eyelid surgery were excluded. Participants were randomly assigned (1:1), with random block sizes of four or six, to receive oral doxycycline (100 mg once a day) or placebo for 28 days immediately after trichiasis surgery. Randomisation was stratified by surgeon. Patients, investigators, surgeons, and all other study team members were masked to study group allocation and treatment. Participants were examined at 10 days, and 1, 6, and 12 months after surgery. The primary outcome was the cumulative proportion of individuals who developed postoperative trichiasis by 12 months. Primary analyses were done in all participants who attended at least one of the four follow-up assessments. Safety analyses were done in all participants who attended either the 10 day or 1 month follow-up assessments. This trial is registered with the Pan African Clinical Trials Registry, number PACTR201512001370307. FINDINGS Between Dec 21, 2015, and April 6, 2016, 1000 patients with trichiasis were enrolled and randomly assigned to treatment (499 patients to doxycycline, 501 patients to placebo). All but one participant attended at least one follow-up assessment. Thus, 999 participants were assessed for the primary outcome: 498 in the doxycycline group and 501 in the placebo group. By month 12, 58 (12%) of 498 patients in the doxycycline group and 62 (12%) of 501 patients in the placebo group had developed postoperative trichiasis (adjusted odds ratio 0·91, 95% CI 0·61 to 1·34, p=0·63), with a risk difference of -0·5% (-4·5% to 3·5%). Significantly more patients in the doxycycline group had an adverse event than in the placebo group (18 [4%] of 498 vs six [1%] of 501; odds ratio 3·09, 95% CI 1·21-7·84; p=0·02). The most frequent adverse events in the doxycycline group were gastritis symptoms (n=9), constipation (n=4), and diarrhoea (n=4). INTERPRETATION Doxycycline did not reduce the risk of postoperative trichiasis and is therefore not indicated for the improvement of outcomes following trachomatous trichiasis surgery. Surgical programmes should continue to make efforts to strengthen surgical training and supervision to improve outcomes. FUNDING The Wellcome Trust.
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Affiliation(s)
- Esmael Habtamu
- International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, UK.
| | | | | | | | | | | | - Chrissy H Roberts
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | | | - David C W Mabey
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, UK
| | - Saul N Rajak
- International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, UK
| | | | - David Macleod
- Medical Research Council Tropical Epidemiology Group, London School of Hygiene & Tropical Medicine, London, UK
| | - Helen A Weiss
- Medical Research Council Tropical Epidemiology Group, London School of Hygiene & Tropical Medicine, London, UK
| | - Matthew J Burton
- International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, UK
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Gower EW. Reducing the risk of postoperative trichiasis: lessons from a clinical trial. LANCET GLOBAL HEALTH 2018; 6:e483-e484. [PMID: 29653615 DOI: 10.1016/s2214-109x(18)30193-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 03/14/2018] [Indexed: 10/17/2022]
Affiliation(s)
- Emily W Gower
- Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27516, USA.
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Predictors of Trachomatous Trichiasis Surgery Outcome. Ophthalmology 2017; 124:1143-1155. [PMID: 28438414 PMCID: PMC5540045 DOI: 10.1016/j.ophtha.2017.03.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Revised: 03/07/2017] [Accepted: 03/08/2017] [Indexed: 11/24/2022] Open
Abstract
Purpose Unfavorable outcomes after trachomatous trichiasis (TT) surgery are undermining the global trachoma elimination effort. This analysis investigates predictors of postoperative TT (PTT), eyelid contour abnormalities (ECAs), and granuloma in the 2 most common TT surgery procedures: posterior lamellar tarsal rotation (PLTR) and bilamellar tarsal rotation (BLTR). Design Secondary data analysis from a randomized, controlled, single-masked clinical trial. Participants A total of 1000 patients with TT, with lashes touching the eye or evidence of epilation, in association with tarsal conjunctival scarring. Methods Participants were randomly allocated and received BLTR (n = 501) or PLTR (n = 499) surgery. Disease severity at baseline, surgical incisions, sutures, and corrections were graded during and immediately after surgery. Participants were examined at 6 and 12 months by assessors masked to allocation. Main Outcome Measures Predictors of PTT, ECA, and granuloma. Results Data were available for 992 (99.2%) trial participants (496 in each arm). There was strong evidence that performing more peripheral dissection with scissors in PLTR (odd ratio [OR], 0.70; 95% confidence interval [CI], 0.54–0.91; P = 0.008) and BLTR (OR, 0.83; 95% CI, 0.72–0.96; P = 0.01) independently protected against PTT. Baseline major trichiasis and mixed location lashes and immediate postoperative central undercorrection independently predicted PTT in both surgical procedures. Peripheral lashes in PLTR (OR, 5.91; 95% CI, 1.48–23.5; P = 0.01) and external central incision height ≥4 mm in BLTR (OR, 2.89; 95% CI, 1.55–5.41; P = 0.001) were independently associated with PTT. Suture interval asymmetry of >2 mm (OR, 3.18; 95% CI, 1.31–7.70; P = 0.01) in PLTR and baseline conjunctival scarring in BLTR (OR, 1.72; 95% CI, 1.06–2.81; P = 0.03) were independently associated with ECA. Older age was independently associated with ECA in both PLTR (P value for trend < 0.0001) and BLTR (P value for trend = 0.03). There was substantial intersurgeon variability in ECA rates for both PLTR (range, 19.0%–36.2%) and BLTR (range, 6.1%–28.7%) procedures. In PLTR surgery, irregular posterior lamellar incision at the center of the eyelid (OR, 6.72; 95% CI, 1.55–29.04; P = 0.01) and ECA (OR, 3.08; 95% CI, 1.37–6.94; P = 0.007) resulted in granuloma formation. Conclusions Poor postoperative outcomes in TT surgery were associated with inadequate peripheral dissection, irregular incision, asymmetric suture position and tension, inadequate correction, and lash location. Addressing these will improve TT surgical outcomes.
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Ramyil A, Bascaran C, Bunce C, Alada J, Wade P, Mpyet C. Outcome of trachoma lid surgeries in Jigawa state, Nigeria. COGENT MEDICINE 2016. [DOI: 10.1080/2331205x.2016.1233683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Affiliation(s)
- Alice Ramyil
- Department of Ophthalmology, University of Jos and Jos University Teaching Hospital, Jos, Nigeria
| | - Covadonga Bascaran
- International Centre for Eye Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Catey Bunce
- International Centre for Eye Health, London School of Hygiene and Tropical Medicine, London, UK
- University College London (UCL), London, UK
| | - Joel Alada
- Department of Ophthalmology, University of Jos and Jos University Teaching Hospital, Jos, Nigeria
| | - Patricia Wade
- Department of Ophthalmology, University of Jos and Jos University Teaching Hospital, Jos, Nigeria
| | - Caleb Mpyet
- Department of Ophthalmology, University of Jos and Jos University Teaching Hospital, Jos, Nigeria
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Butcher RMR, Sokana O, Jack K, Macleod CK, Marks ME, Kalae E, Sui L, Russell C, Tutill HJ, Williams RJ, Breuer J, Willis R, Le Mesurier RT, Mabey DCW, Solomon AW, Roberts CH. Low Prevalence of Conjunctival Infection with Chlamydia trachomatis in a Treatment-Naïve Trachoma-Endemic Region of the Solomon Islands. PLoS Negl Trop Dis 2016; 10:e0004863. [PMID: 27603015 PMCID: PMC5014345 DOI: 10.1371/journal.pntd.0004863] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 06/29/2016] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Trachoma is endemic in several Pacific Island states. Recent surveys across the Solomon Islands indicated that whilst trachomatous inflammation-follicular (TF) was present at levels warranting intervention, the prevalence of trachomatous trichiasis (TT) was low. We set out to determine the relationship between chlamydial infection and trachoma in this population. METHODS We conducted a population-based trachoma prevalence survey of 3674 individuals from two Solomon Islands provinces. Participants were examined for clinical signs of trachoma. Conjunctival swabs were collected from all children aged 1-9 years. We tested swabs for Chlamydia trachomatis (Ct) DNA using droplet digital PCR. Chlamydial DNA from positive swabs was enriched and sequenced for use in phylogenetic analysis. RESULTS We observed a moderate prevalence of TF in children aged 1-9 years (n = 296/1135, 26.1%) but low prevalence of trachomatous inflammation-intense (TI) (n = 2/1135, 0.2%) and current Ct infection (n = 13/1002, 1.3%) in children aged 1-9 years, and TT in those aged 15+ years (n = 2/2061, 0.1%). Ten of 13 (76.9%) cases of infection were in persons with TF or TI (p = 0.0005). Sequence analysis of the Ct-positive samples yielded 5/13 (38%) complete (>95% coverage of reference) genome sequences, and 8/13 complete plasmid sequences. Complete sequences all aligned most closely to ocular serovar reference strains. DISCUSSION The low prevalence of TT, TI and Ct infection that we observed are incongruent with the high proportion of children exhibiting signs of TF. TF is present at levels that apparently warrant intervention, but the scarcity of other signs of trachoma indicates the phenotype is mild and may not pose a significant public health threat. Our data suggest that, whilst conjunctival Ct infection appears to be present in the region, it is present at levels that are unlikely to be the dominant driving force for TF in the population. This could be one reason for the low prevalence of TT observed during the study.
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Affiliation(s)
- Robert M. R. Butcher
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Oliver Sokana
- Eye Department, Solomon Islands Ministry of Health and Medical Services, Honiara, Solomon Islands
| | - Kelvin Jack
- Eye Department, Solomon Islands Ministry of Health and Medical Services, Honiara, Solomon Islands
| | - Colin K. Macleod
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Sightsavers, Haywards Heath, United Kingdom
| | - Michael E. Marks
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Hospital for Tropical Diseases, University College London Hospitals, London, United Kingdom
| | - Eric Kalae
- Primary Care Department, Lata Hospital, Lata, Santa Cruz, Solomon Islands
| | - Leslie Sui
- Primary Care Department, Lata Hospital, Lata, Santa Cruz, Solomon Islands
| | | | - Helena J. Tutill
- Division of Infection & Immunity, Faculty of Medical Sciences, University College London, London, United Kingdom
| | - Rachel J. Williams
- Division of Infection & Immunity, Faculty of Medical Sciences, University College London, London, United Kingdom
| | - Judith Breuer
- Division of Infection & Immunity, Faculty of Medical Sciences, University College London, London, United Kingdom
| | - Rebecca Willis
- Task Force for Global Health, Decatur, Georgia, United States of America
| | - Richard T. Le Mesurier
- Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - David C. W. Mabey
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Hospital for Tropical Diseases, University College London Hospitals, London, United Kingdom
| | - Anthony W. Solomon
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Chrissy h. Roberts
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Hu VH, Luthert PJ, Derrick T, Pullin J, Weiss HA, Massae P, Mtuy T, Makupa W, Essex D, Mabey DCW, Bailey RL, Holland MJ, Burton MJ. Immunohistochemical Analysis of Scarring Trachoma Indicates Infiltration by Natural Killer and Undefined CD45 Negative Cells. PLoS Negl Trop Dis 2016; 10:e0004734. [PMID: 27219121 PMCID: PMC4878762 DOI: 10.1371/journal.pntd.0004734] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 05/03/2016] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION The phenotype and function of immune cells infiltrating the conjunctiva in scarring trachoma have yet to be fully characterized. We assessed tissue morphology and immunophenotype of cellular infiltrates found in trachomatous scarring compared to control participants. METHODOLOGY Clinical assessments and conjunctival biopsy samples were obtained from 34 individuals with trachomatous scarring undergoing trichiasis surgery and 33 control subjects undergoing cataract or retinal detachment surgery. Biopsy samples were fixed in buffered formalin and embedded in paraffin wax. Hematoxylin and eosin (H&E) staining was performed for assessment of the inflammatory cell infiltrate. Immunohistochemical staining of single markers on individual sections was performed to identify cells expressing CD3 (T-cells), CD4 (helper T-cells), CD8 (suppressor/cytotoxic T-cells and Natural Killer, NK, cells), NCR1 (NK cells), CD20 (B-cells), CD45 (nucleated hematopoietic cells), CD56 (NK and T-cells), CD68 (macrophages/monocytes) and CD83 (mature dendritic cells). The degree of scarring was assessed histologically using cross-polarized light to visualize collagen fibres. PRINCIPLE FINDINGS Scarring, regardless of clinical inflammation, was associated with increased inflammatory cell infiltrates on H&E and CD45 staining. Scarring was also associated with increased CD8+ and CD56+ cells, but not CD3+ cells, suggestive of a NK cell infiltrate. This was supported by the presence of NCR1+ cells. There was some increase in CD20+ cells, but no evidence for increased CD4+, CD68+ or CD83+ cells. Numerous CD45 negative cells were also seen in the population of infiltrating inflammatory cells in scarred conjunctiva. Disorganization of the normal collagen architecture was strongly associated with clinical scarring. CONCLUSIONS/SIGNIFICANCE These data point to the infiltration of immune cells with a phenotype suggestive of NK cells in conjunctival trachomatous scarring. A large proportion of CD45 negative inflammatory cells were also present. Future work should seek to understand the stimuli leading to the recruitment of these cells and their role in progressive scarring.
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Affiliation(s)
- Victor H. Hu
- International Centre for Eye Health, Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | | | - Tamsyn Derrick
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - James Pullin
- UCL Institute of Ophthalmology, London, United Kingdom
| | - Helen A. Weiss
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Tara Mtuy
- International Centre for Eye Health, Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | | | - David Essex
- UCL Institute of Ophthalmology, London, United Kingdom
| | - David C. W. Mabey
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Robin L. Bailey
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin J. Holland
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- International Centre for Eye Health, Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
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Habtamu E, Wondie T, Aweke S, Tadesse Z, Zerihun M, Mohammed A, Zewudie Z, Callahan K, Emerson PM, Bailey RL, Mabey DCW, Rajak SN, Kuper H, Polack S, Weiss HA, Burton MJ. Impact of Trichiasis Surgery on Quality of Life: A Longitudinal Study in Ethiopia. PLoS Negl Trop Dis 2016; 10:e0004627. [PMID: 27078493 PMCID: PMC4831752 DOI: 10.1371/journal.pntd.0004627] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/23/2016] [Indexed: 12/30/2022] Open
Abstract
Background Trachomatous trichiasis significantly reduces vision and health related quality of life (QoL). Although trichiasis surgery is widely performed to treat trichiasis, there is little data on the effect of surgery on QoL. We measured the impact of trichiasis surgery on vision and health related QoL in a longitudinal study from Amhara Region, Ethiopia. Methodology/Principal Findings We recruited 1000 adult participants with trichiasis (cases) and 200 comparison participants, matched to every fifth trichiasis case on age (+/- two years), sex and location. Vision-related quality of life (VRQoL) and health-related quality of life (HRQoL) were measured using the WHO/PBD-VF20 and WHOQOL-BREF questionnaires respectively, at enrolment and 12 months after enrolment. All trichiasis cases received free standard trichiasis surgery immediately after enrolment. The mean difference in QoL scores between enrolment and follow-up for cases and comparison participants, and the difference-in-differences by baseline trichiasis status was analysed using random effects linear regression, the later adjusted for age, sex and socioeconomic status. At 12-months follow-up, data was collected from 980 (98%) and 198 (98%) trichiasis cases and comparison participants respectively. At this follow-up visit, VRQoL and HRQoL scores of trichiasis cases improved substantially in all subscales and domains by 19.1–42.0 points (p<0.0001) and 4.7–17.2 points (p<0.0001), respectively. In contrast, among the comparison participants, there was no evidence of improvement in VRQoL and HRQoL domain scores during follow-up. The improvement in VRQoL and HRQoL in cases was independent of the presence of visual acuity improvement at 12 months. Conclusions/Significance Trichiasis surgery substantially improves both VRQoL and HRQoL regardless of visual acuity change. Unprecedented effort is needed to scale-up trichiasis surgical programmes not only to prevent the risk of sight loss but also to improve overall wellbeing and health perception of affected individuals. We previously reported that Trachomatous Trichiasis (TT) has a profound impact on vision and heath related quality of life (QoL), even when vision is not impaired. The World Health Organization (WHO) recommends corrective eyelid surgery for trichiasis to reduce the risk of vision loss. However, trichiasis surgery may also improve overall wellbeing. There is very limited evidence on the long-term impact of trichiasis surgery on QoL. We measured vision and health-related quality of life of 1000 TT patients before and one year after receiving TT surgery and compared the QoL scores of these with the baseline and 1 year follow-up QoL score of 200 matched individuals who have never had trichiasis or trichiasis surgery. We found strong evidence that surgery substantially improves both vision and heath related QoL of TT case, even when there is no improvement in vision; while there was no evidence of improvement in the QoL of the trichiasis free participants. The results provide clear evidence that the benefit of trichiasis surgery goes beyond preventing the risk of blindness and improves the overall wellbeing and health perception of affected individuals, indicating the need to provide prompt surgical intervention for affected individuals.
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Affiliation(s)
- Esmael Habtamu
- International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
- The Carter Center, Addis Ababa, Ethiopia
- * E-mail:
| | | | | | | | | | | | | | - Kelly Callahan
- The Carter Center, Atlanta, Georgia, United States of America
| | - Paul M. Emerson
- International Trachoma Initiative, Atlanta, Georgia, United States of America
| | - Robin L. Bailey
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - David C. W. Mabey
- Clinical Research Department, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Saul N. Rajak
- International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Hannah Kuper
- International Centre for Evidence in Disability, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Sarah Polack
- International Centre for Evidence in Disability, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Helen A. Weiss
- MRC Tropical Epidemiology Group, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Matthew J. Burton
- International Centre for Eye Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Corneal Sensitivity and Presence of Pathogenic Organisms Among Participants Who Have Undergone Trichiasis Surgery Differ by Surgical Outcome. Cornea 2016; 35:513-8. [PMID: 26890661 DOI: 10.1097/ico.0000000000000746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To explore the potential association between reduced corneal sensation and/or conjunctival bacterial colonization and postoperative trichiasis and eyelid contour abnormalities after corrective eyelid surgery among participants with a history of trachomatous trichiasis. METHODS As an ancillary study to the Partnership for Rapid Elimination of Trachoma (PRET) Surgery Trial in southern Tanzania, we collected data on 580 PRET participants who had undergone trichiasis surgery 1 year earlier and 200 age-group-matched individuals without trichiasis. Assessments included eyelid status evaluation (presence and severity of postoperative trichiasis and/or eyelid contour abnormality), corneal sensitivity by Cochet-Bonnet aesthesiometer, a questionnaire on symptoms of ocular irritation, and conjunctival microbiology. We divided PRET participants based on their eyelid status and compared results across PRET groups and versus normals. RESULTS PRET participants had reduced corneal sensitivity compared with age-matched normals (mean sensitivity ranged from 2.8 to 3.8 cm in PRET participants vs. 5.9 cm in normals), and increasing severity of postoperative trichiasis was associated in a stepwise fashion with reduced corneal sensitivity (mean = 3.5 cm for mild and 2.6 cm for severe postoperative trichiasis). Conjunctival colonization with pathogenic bacteria was also associated with more severe postoperative trichiasis (Cochran-Armitage trend test P = 0.001) and with reduced corneal sensitivity (trend test P < 0.0001). Symptoms of ocular irritation were not associated with previous trichiasis surgery, postoperative trichiasis, or eyelid contour abnormality. CONCLUSIONS These findings indicate that reduced corneal sensitivity accompanies trachomatous trichiasis and suggest that reduced corneal sensitivity may play an important role in the harboring of pathogenic bacteria on the ocular surface.
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Habtamu E, Wondie T, Aweke S, Tadesse Z, Zerihun M, Zewudie Z, Kello AB, Roberts CH, Emerson PM, Bailey RL, Mabey DCW, Rajak SN, Callahan K, Weiss HA, Burton MJ. Posterior lamellar versus bilamellar tarsal rotation surgery for trachomatous trichiasis in Ethiopia: a randomised controlled trial. Lancet Glob Health 2016; 4:e175-84. [PMID: 26774708 PMCID: PMC5075282 DOI: 10.1016/s2214-109x(15)00299-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 11/29/2015] [Accepted: 12/03/2015] [Indexed: 01/06/2023]
Abstract
BACKGROUND Eyelid surgery is done to correct trachomatous trichiasis to prevent blindness. However, recurrent trichiasis is frequent. Two procedures are recommended by WHO and are in routine practice: bilamellar tarsal rotation (BLTR) and posterior lamellar tarsal rotation (PLTR). This study was done to identify which procedure gives the better results. METHODS A randomised, controlled, single masked clinical trial was done in Ethiopia. Participants had upper lid trachomatous trichiasis with one or more eyelashes touching the eye or evidence of epilation, in association with tarsal conjunctival scarring. Exclusion criteria were age less than 18 years, recurrent trichiasis after previous surgery, hypertension, and pregnancy. Participants were randomly assigned (1:1) to either BLTR or PLTR surgery, stratified by surgeon. The sequences were computer-generated by an independent statistician. Surgery was done in a community setting following WHO guidelines. Participants were examined at 6 months and 12 months by assessors masked to allocation. The primary outcome was the cumulative proportion of individuals who developed recurrent trichiasis by 12 months. Primary analyses were by modified intention to treat. The intervention effect was estimated by logistic regression, controlled for surgeon as a fixed effect in the model. The trial is registered with the Pan African Clinical Trials Registry (number PACTR201401000743135). FINDINGS 1000 participants with trichiasis were recruited, randomly assigned, and treated (501 in the BLTR group and 499 in the PLTR group) between Feb 13, 2014, and May 31, 2014. Eight participants were not seen at either 6 month or 12 month follow-up visits and were excluded from the analysis: three from the PLTR group and five from the BLTR group. The follow-up rate at 12 months was 98%. Cumulative recurrent trichiasis by 12 months was more frequent in the BLTR group than in the PLTR group (110/496 [22%] vs 63/496 [13%]; adjusted odds ratio [OR] 1·96 [95% CI 1·40-2·75]; p=0·0001), with a risk difference of 9·50% (95% CI 4·79-14·16). INTERPRETATION PLTR surgery was superior to BLTR surgery for management of trachomatous trichiasis, and could be the preferred procedure for the programmatic management of trachomatous trichiasis. FUNDING The Wellcome Trust.
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Affiliation(s)
- Esmael Habtamu
- London School of Hygiene & Tropical Medicine, London, UK,The Carter Center, Addis Ababa, Ethiopia
| | | | | | | | | | | | | | | | | | - Robin L Bailey
- London School of Hygiene & Tropical Medicine, London, UK
| | | | - Saul N Rajak
- London School of Hygiene & Tropical Medicine, London, UK
| | | | - Helen A Weiss
- London School of Hygiene & Tropical Medicine, London, UK
| | - Matthew J Burton
- London School of Hygiene & Tropical Medicine, London, UK,Correspondence to: Dr Matthew J Burton, International Centre for Eye Health, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UKCorrespondence to: Dr Matthew J BurtonInternational Centre for Eye HealthFaculty of Infectious and Tropical DiseasesLondon School of Hygiene & Tropical MedicineKeppel StreetLondonWC1E 7HTUK
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Abstract
BACKGROUND Trachoma is the leading infectious cause of blindness. The World Health Organization (WHO) recommends eliminating trachomatous blindness through the SAFE strategy: Surgery for trichiasis, Antibiotic treatment, Facial cleanliness and Environmental hygiene. This is an update of a Cochrane review first published in 2003, and previously updated in 2006. OBJECTIVES To assess the effects of interventions for trachomatous trichiasis for people living in endemic settings. SEARCH METHODS We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2015, Issue 4), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to May 2015), EMBASE (January 1980 to May 2015), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 7 May 2015. We searched the reference lists of included studies to identify further potentially relevant studies. We also contacted authors for details of other relevant studies. SELECTION CRITERIA We included randomised trials of any intervention intended to treat trachomatous trichiasis. DATA COLLECTION AND ANALYSIS Three review authors independently selected and assessed the trials, including the risk of bias. We contacted trial authors for missing data when necessary. Our primary outcome was post-operative trichiasis which was defined as any lash touching the globe at three months, one year or two years after surgery. MAIN RESULTS Thirteen studies met the inclusion criteria with 8586 participants. Most of the studies were conducted in sub-Saharan Africa. The majority of the studies were of a low or unclear risk of bias.Five studies compared different surgical interventions. Most surgical interventions were performed by non-physician technicians. These trials suggest the most effective surgery is full-thickness incision of the tarsal plate and rotation of the terminal tarsal strip. Pooled data from two studies suggested that the bilamellar rotation was more effective than unilamellar rotation (OR 0.29, 95% CI 0.16 to 0.50). Use of a lid clamp reduced lid contour abnormalities (OR 0.65, 95% CI 0.44 to 0.98) and granuloma formation (OR 0.67, 95% CI 0.46 to 0.97). Absorbable sutures gave comparable outcomes to silk sutures (OR 0.90, 95% CI 0.68 to 1.20) and were associated with less frequent granuloma formation (OR 0.63, 95% CI 0.40 to 0.99). Epilation was less effective at preventing eyelashes from touching the globe than surgery for mild trichiasis, but had comparable results for vision and corneal change. Peri-operative azithromycin reduced post-operative trichiasis; however, the estimate of effect was imprecise and compatible with no effect or increased trichiasis (OR 0.85, 95% CI 0.63 to 1.14; 1954 eyes; 3 studies). Community-based surgery when compared to health centres increased uptake with comparable outcomes. Surgery performed by ophthalmologists and integrated eye care workers was comparable. Adverse events were typically infrequent or mild and included rare postoperative infections, eyelid contour abnormalities and conjunctival granulomas. AUTHORS' CONCLUSIONS No trials were designed to evaluate whether the interventions for trichiasis prevent blindness as an outcome; however, several found modest improvement in vision following intervention. Certain interventions have been shown to be more effective at eliminating trichiasis. Full-thickness incision of the tarsal plate and rotation of the lash-bearing lid margin was found to be the best technique and is preferably delivered in the community. Surgery may be carried out by an ophthalmologist or a trained ophthalmic assistant. Surgery performed with silk or absorbable sutures gave comparable results. Post-operative azithromycin was found to improve outcomes where overall recurrence was low.
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Affiliation(s)
- Matthew Burton
- London School of Hygiene & Tropical MedicineInternational Centre for Eye HealthKeppel StreetLondonUKWC1E 7HT
| | - Esmael Habtamu
- London School of Hygiene and Tropical MedicineKeppel StreetLondonUKWC1E 7HT
| | | | - Emily W Gower
- Wake Forest Public Health Sciences and OphthalmologyMedical Center BlvdWinston‐SalemNCUSA27157
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Abera B, Kibret M. Azithromycin, fluoroquinolone and chloramphenicol resistance of non-chlamydia conjunctival bacteria in rural community of Ethiopia. Indian J Ophthalmol 2015; 62:236-9. [PMID: 23571246 PMCID: PMC4005243 DOI: 10.4103/0301-4738.99974] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aim: To determine profiles of non-chlamydia conjunctival bacteria and their antimicrobial susceptibility from adults who underwent trachomatous trichiasis surgery in rural areas of Ethiopia. Materials and Methods: A cross-sectional study was conducted in rural districts in West Gojjam administrative zone. Conjunctival swabs were collected during surgery and transported using Stuart transport broth (Oxoid, UK). Antibiotic susceptibility of conjunctival isolates was determined using the Kirby-Bauer disc-diffusion method. Results: Non-chlamydia pathogenic bacteria were recovered from conjunctiva of 438 (31%) participants before treatment. The isolated conjunctival bacteria were Staphylococcus aureus, coagulase-negative Staphylococci, Streptococcus group (A, C, F and G), Enterococci, Streptococcus pneumoniae, Moraxella spp., Escherichia coli, Citrobacter spp., Proteus spp., Klebsiella spp., Pseudomonas spp. and Enterobacter spp. Overall, resistance rates of 57.8% to azithromycin and 68.5% to chloramphenicol were found. However, 86-94.4% sensitivity was demonstrated to ciprofloxacin and norfloxacin. Moderate sensitivity rates (61.8-78.4%) were observed to ceftriaxone, tetracycline and cotrimoxazole. Conclusion: Fluoroquinolones that have activity against the majority of bacterial isolates were potent at in vitro. However, unacceptably high levels of resistance to azithromycin and chloramphenicol in rural community indicated a need for further study and antimicrobial resistance surveillance.
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Affiliation(s)
- Bayeh Abera
- Department of Medical Microbiology, College of Medicine and Health Sciences, Ethiopia
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Smith JL, Sivasubramaniam S, Rabiu MM, Kyari F, Solomon AW, Gilbert C. Multilevel Analysis of Trachomatous Trichiasis and Corneal Opacity in Nigeria: The Role of Environmental and Climatic Risk Factors on the Distribution of Disease. PLoS Negl Trop Dis 2015. [PMID: 26222549 PMCID: PMC4519340 DOI: 10.1371/journal.pntd.0003826] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The distribution of trachoma in Nigeria is spatially heterogeneous, with large-scale trends observed across the country and more local variation within areas. Relative contributions of individual and cluster-level risk factors to the geographic distribution of disease remain largely unknown. The primary aim of this analysis is to assess the relationship between climatic factors and trachomatous trichiasis (TT) and/or corneal opacity (CO) due to trachoma in Nigeria, while accounting for the effects of individual risk factors and spatial correlation. In addition, we explore the relative importance of variation in the risk of trichiasis and/or corneal opacity (TT/CO) at different levels. Data from the 2007 National Blindness and Visual Impairment Survey were used for this analysis, which included a nationally representative sample of adults aged 40 years and above. Complete data were available from 304 clusters selected using a multi-stage stratified cluster-random sampling strategy. All participants (13,543 individuals) were interviewed and examined by an ophthalmologist for the presence or absence of TT and CO. In addition to field-collected data, remotely sensed climatic data were extracted for each cluster and used to fit Bayesian hierarchical logistic models to disease outcome. The risk of TT/CO was associated with factors at both the individual and cluster levels, with approximately 14% of the total variation attributed to the cluster level. Beyond established individual risk factors (age, gender and occupation), there was strong evidence that environmental/climatic factors at the cluster-level (lower precipitation, higher land surface temperature, higher mean annual temperature and rural classification) were also associated with a greater risk of TT/CO. This study establishes the importance of large-scale risk factors in the geographical distribution of TT/CO in Nigeria, supporting anecdotal evidence that environmental conditions are associated with increased risk in this context and highlighting their potential use in improving estimates of disease burden at large scales. Trichiasis (TT) and corneal opacity (CO) are chronic stages of trachoma, which remains an important cause of blindness. This study used multilevel spatial models to investigate risk factors for TT/CO in Nigeria, including data for more than 13,500 adults aged 40 years and above collected in the 2007 National Blindness and Visual Impairment survey. Individual-level risk factors were consistent with those identified in other studies, including a higher risk in females, older individuals and those with lower socioeconomic status. After controlling for these factors, there was evidence that a number of environmental and climatic factors are associated with the distribution of TT/CO in Nigeria. These findings establish for the Nigerian context the importance of risk factors at different scales for the later stages of trachoma, supporting anecdotal evidence that hotter, drier environmental conditions are associated with increased risk.
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Affiliation(s)
- Jennifer L. Smith
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Global Health Group, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
| | - Selvaraj Sivasubramaniam
- Medical Statistics Team, Division of Applied Health Sciences, University of Aberdeen, United Kingdom
| | | | - Fatima Kyari
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- College of Health Sciences of University of Abuja, Abuja, Nigeria
| | - Anthony W. Solomon
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Clare Gilbert
- Department of Clinical Research, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
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Merbs SL, Oktavec KC, Munoz BE, Perlini EF, West SK, Othman MS, Gower EW. Lower Postoperative Scar Height is Associated with Increased Postoperative Trichiasis 1 Year after Bilamellar Tarsal Rotation Surgery. Ophthalmic Epidemiol 2015; 22:200-7. [DOI: 10.3109/09286586.2015.1036299] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Warren JM, Birrell AL. Trachoma in remote Indigenous Australia: a review and public health perspective. Aust N Z J Public Health 2015; 40 Suppl 1:S48-52. [PMID: 26123218 DOI: 10.1111/1753-6405.12396] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/01/2015] [Accepted: 02/01/2015] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES Trachoma remains a major health concern in many remote Indigenous Australian communities, despite behaviour-modifying and biomedical strategies. This review aims to examine the social epidemiology of trachoma in remote Indigenous communities and identify practical, sustainable strategies to alter the social determinants of the disease. METHODS A systematic search and critical review explored the proximal, intermediate and distal determinants of trachoma. The impact of swimming pools in remote Indigenous communities on trachoma and other infectious diseases was further examined. RESULTS Having a clean face was found to be protective for trachoma, but face-washing education programs have produced no significant benefits. Sanitation infrastructure in a community was the key determinant of facial cleanliness. Installation of swimming pools in remote Indigenous communities has been demonstrated to reduce the prevalence of several common childhood infections. However, minimal research has explored the impact of pools on trachoma rates. CONCLUSIONS The locally supported construction of pools in remote Indigenous communities may contribute to a decline in trachoma. A prospective, controlled trial is needed to test this hypothesis in endemic communities. IMPLICATIONS If validated by a well-designed study, pool construction may provide a much sought-after practical government strategy to combat trachoma in remote Indigenous communities.
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Pathogenesis of progressive scarring trachoma in Ethiopia and Tanzania and its implications for disease control: two cohort studies. PLoS Negl Trop Dis 2015; 9:e0003763. [PMID: 25970613 PMCID: PMC4430253 DOI: 10.1371/journal.pntd.0003763] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 04/15/2015] [Indexed: 11/19/2022] Open
Abstract
Background Trachoma causes blindness through a conjunctival scarring process initiated by ocular Chlamydia trachomatis infection; however, the rates, drivers and pathophysiological determinants are poorly understood. We investigated progressive scarring and its relationship to conjunctival infection, inflammation and transcript levels of cytokines and fibrogenic factors. Methodology/Principal Findings We recruited two cohorts, one each in Ethiopia and Tanzania, of individuals with established trachomatous conjunctival scarring. They were followed six-monthly for two years, with clinical examinations and conjunctival swab sample collection. Progressive scarring cases were identified by comparing baseline and two-year photographs, and compared to individuals without progression. Samples were tested for C. trachomatis by PCR and transcript levels of S100A7, IL1B, IL13, IL17A, CXCL5, CTGF, SPARCL1, CEACAM5, MMP7, MMP9 and CD83 were estimated by quantitative RT-PCR. Progressive scarring was found in 135/585 (23.1%) of Ethiopian participants and 173/577 (30.0%) of Tanzanian participants. There was a strong relationship between progressive scarring and increasing inflammatory episodes (Ethiopia: OR 5.93, 95%CI 3.31–10.6, p<0.0001. Tanzania: OR 5.76, 95%CI 2.60–12.7, p<0.0001). No episodes of C. trachomatis infection were detected in the Ethiopian cohort and only 5 episodes in the Tanzanian cohort. Clinical inflammation, but not scarring progression, was associated with increased expression of S100A7, IL1B, IL17A, CXCL5, CTGF, CEACAM5, MMP7, CD83 and reduced SPARCL1. Conclusions/Significance Scarring progressed in the absence of detectable C. trachomatis, which raises uncertainty about the primary drivers of late-stage trachoma. Chronic conjunctival inflammation appears to be central and is associated with enriched expression of pro-inflammatory factors and altered expression of extracellular matrix regulators. Host determinants of scarring progression appear more complex and subtle than the features of inflammation. Overall this indicates a potential role for anti-inflammatory interventions to interrupt progression and the need for trichiasis disease surveillance and surgery long after chlamydial infection has been controlled at community level. Blinding trachoma is believed to be the end result of a long-term progressive scarring process that is initiated by recurrent infection by the bacterium Chlamydia trachomatis starting in childhood. Scar tissue predominantly develops on the inner surface of the upper eyelids (conjunctiva). However, the rates, drivers and pathophysiological determinants are poorly understood. We investigated progressive scarring and its relationship to conjunctival infection, inflammation and transcript levels of cytokines and fibrogenic factors in two cohorts of adults in Tanzania and Ethiopia. These groups of people already had a degree of scarring and were regularly followed-up with over a two-year period. We found scarring progressed in about a quarter of people over this time. The progression was closely associated with episodes of conjunctival inflammation but not to the detection of C. trachomatis infection. This raises uncertainty about the primary drivers of late-stage trachoma. Chronic conjunctival inflammation appears to be central and is associated with enriched expression of pro-inflammatory factors and altered expression of extracellular matrix regulators. Host determinants of scarring progression appear more complex and subtle than the features of inflammation. Overall this indicates the likely need for trichiasis disease surveillance and surgery long after chlamydial infection has been controlled at community level.
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Habtamu E, Rajak SN, Tadesse Z, Wondie T, Zerihun M, Guadie B, Gebre T, Kello AB, Callahan K, Mabey DCW, Khaw PT, Gilbert CE, Weiss HA, Emerson PM, Burton MJ. Epilation for minor trachomatous trichiasis: four-year results of a randomised controlled trial. PLoS Negl Trop Dis 2015; 9:e0003558. [PMID: 25768796 PMCID: PMC4358978 DOI: 10.1371/journal.pntd.0003558] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 01/22/2015] [Indexed: 11/19/2022] Open
Abstract
Background Trachomatous trichiasis (TT) needs to be managed to reduce the risk of vision loss. The long-term impact of epilation (a common traditional practice of repeated plucking of lashes touching the eye) in preventing visual impairment and corneal opacity from TT is unknown. We conducted a randomized controlled trial of epilation versus surgery for the management of minor TT (fewer than six lashes touching the eye) in Ethiopia. Here we report the four-year outcome and the effect on vision and corneal opacity. Methodology/ Principal Findings 1300 individuals with minor TT were recruited and randomly assigned to quality trichiasis surgery or repeated epilation using high quality epilation forceps by a trained person with good near vision. Participants were examined six-monthly for two-years, and then at four-years after randomisation. At two-years all epilation arm participants were offered free surgery. At four-years 1151 (88.5%) were re-examined: 572 (88%) and 579 (89%) from epilation and surgery arms, respectively. At that time, 21.1% of the surgery arm participants had recurrent TT; 189/572 (33%) of the epilation arm had received surgery, while 383 (67%) declined surgery and had continued epilating (“epilation-only”). Among the epilation-only group, 207 (54.1%) fully controlled their TT, 166 (43.3%) had minor TT and 10 (2.6%) had major TT (>5 lashes). There were no differences between participants in the epilation-only, epilation-to-surgery and surgery arm participants in changes in visual acuity and corneal opacity between baseline and four-years. Conclusions/ Significance Most minor TT participants randomised to the epilation arm continued epilating and controlled their TT. Change in vision and corneal opacity was comparable between surgery and epilation-only participants. This suggests that good quality epilation with regular follow-up is a reasonable second-line alternative to surgery for minor TT for individuals who either decline surgery or do not have immediate access to surgical treatment. Trachoma causes visual impairment through the effect of in-turned eyelashes (trichiasis) on the surface of the eye. Epilation is a common traditional practice of intermittent plucking of lashes touching the eye, however, its long-term effectiveness in preventing visual impairment is unknown. We conducted a randomized controlled trial of epilation versus eyelid surgery (the main treatment option) in 1300 people with mild trichiasis in Ethiopia. We defined mild trichiasis as fewer than six lashes touching the eye. We have previously reported results to two years and have now re-assessed these individuals at four years. Overall, we found no difference between the epilation and surgery groups in terms of change in vision and corneal opacity between baseline and four years. Most mild trichiasis participants randomised to the epilation arm continued epilating and controlled their trichiasis. This suggests that good quality epilation is a reasonable second-line alternative to surgery for mild trichiasis for individuals who either decline surgery or do not have immediate access to surgical treatment.
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Affiliation(s)
- Esmael Habtamu
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- The Carter Center, Addis Ababa, Ethiopia
| | - Saul N. Rajak
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | | | | | | | - Teshome Gebre
- International Trachoma Initiative, Addis Ababa, Ethiopia
| | | | - Kelly Callahan
- The Carter Center, Atlanta, Georgia, United States of America
| | - David C. W. Mabey
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Peng T. Khaw
- NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom
| | - Clare E. Gilbert
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Helen A. Weiss
- MRC Tropical Epidemiology Group, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Paul M. Emerson
- International Trachoma Initiative, Atlanta, Georgia, United States of America
| | - Matthew J. Burton
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom
- * E-mail:
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Abstract
Trachoma is the most common infectious cause of blindness. Repeated episodes of infection with Chlamydia trachomatis in childhood lead to severe conjunctival inflammation, scarring, and potentially blinding inturned eyelashes (trichiasis or entropion) in later life. Trachoma occurs in resource-poor areas with inadequate hygiene, where children with unclean faces share infected ocular secretions. Much has been learnt about the epidemiology and pathophysiology of trachoma. Integrated control programmes are implementing the SAFE Strategy: surgery for trichiasis, mass distribution of antibiotics, promotion of facial cleanliness, and environmental improvement. This strategy has successfully eliminated trachoma in several countries and global efforts are underway to eliminate blinding trachoma worldwide by 2020.
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Affiliation(s)
- Hugh R Taylor
- Melbourne School of Population and Global Health, University of Melbourne, Carlton, VIC, Australia.
| | - Matthew J Burton
- International Centre for Eye Health, Department of Clinical Research, London School of Hygiene & Tropical Medicine, London, UK
| | - Danny Haddad
- Global Vision Initiative, Emory Eye Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Sheila West
- Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, MD, USA
| | - Heathcote Wright
- Centre for Eye Research Australia, University of Melbourne, East Melbourne, VIC, Australia
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Goldschmidt P, Einterz E. The limits of medical interventions for the elimination of preventable blindness. Trop Med Health 2014; 42:43-52. [PMID: 24808746 PMCID: PMC3965845 DOI: 10.2149/tmh.2013-26] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 12/21/2013] [Indexed: 11/11/2022] Open
Abstract
Background: Health authorities are working toward the global elimination of trachoma by the year 2020 with actions focused on the World Health Organization SAFE strategy (surgery of trichiasis, antibiotics, face washing and environmental changes) with emphasis on hygienist approaches for education. Objectives: The present survey was performed to assess the sustainability of the SAFE strategy 3 years after trachoma was eliminated from 6 villages. Methods: In February 2013 a rapid trachoma assessment was conducted in 6 villages of Kolofata’s district, Extreme north Region, Cameroon, where trachoma was eliminated in 2010. A total of 300 children (1–10 years) from 6 villages were examined by trained staff. Results: The prevalence of active trachoma (children aged > 1 and < 10 years) in 2013 was 15% and in at least 25% was observed absence of face washing and flies in their eyes and nose. Income level, quality of roads, hygiene, and illiteracy were similar in all the villages; they did not change between 2010 and 2013 and could not be analyzed as independent risk factors. Discussion: The heterogeneity of methods described for clinical trials makes it inappropriate to conduct meta-analysis for the present and for other SAFE-related trials. The results obtained after implementation the SAFE strategy (recurrence) reveal that the causes (infectious agents and dirtiness) and effects (illness) were not connected by illiterate people living under conditions of extreme poverty. So far, antibiotics, surgery and hygiene education are insufficient for the sustainability of trachoma elimination and highlight that hypothetic-deductive processes seem not operational after implementing the awareness campaigns. Trachoma recurrence detected in 2013 in sedentary populations of Kolofata receiving efficacious treatments against Chlamydia sp. suggest that the elimination goals will be delayed if strategies are limited to medical actions. Restricting efforts to repeated pharmacological and surgical interventions for people infected with susceptible bacteria could be understood as the hidden side of a passive attitude toward basic education actions.
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Affiliation(s)
- Pablo Goldschmidt
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris France and Ophtalmo sans Frontières, Luçon, France
| | - Ellen Einterz
- Hôpital de District de Kolofata, Far North Region, Cameroon
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Rajak SN, Habtamu E, Weiss HA, Kello AB, Abera B, Zerihun M, Gebre T, Gilbert CE, Khaw PT, Emerson PM, Burton MJ. The outcome of trachomatous trichiasis surgery in Ethiopia: risk factors for recurrence. PLoS Negl Trop Dis 2013; 7:e2392. [PMID: 23991241 PMCID: PMC3749971 DOI: 10.1371/journal.pntd.0002392] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 07/17/2013] [Indexed: 11/23/2022] Open
Abstract
Background Over 1.2 million people are blind from trachomatous trichiasis (TT). Lid rotation surgery is the mainstay of treatment, but recurrence rates can be high. We investigated the outcomes (recurrence rates and other complications) of posterior lamellar tarsal rotation (PLTR) surgery, one of the two most widely practised TT procedures in endemic settings. Methodology/Principal Findings We conducted a two-year follow-up study of 1300 participants who had PLTR surgery, conducted by one of five TT nurse surgeons. None had previously undergone TT surgery. All participants received a detailed trachoma eye examination at baseline and 6, 12, 18 and 24 months post-operatively. The study investigated the recurrence rates, other complications and factors associated with recurrence. Recurrence occurred in 207/635 (32.6%) and 108/641 (16.9%) of participants with pre-operative major (>5 trichiatic lashes) and minor (<5 lashes) TT respectively. Of the 315 recurrences, 42/315 (3.3% overall) had >5 lashes (major recurrence). Recurrence was greatest in the first six months after surgery: 172 cases (55%) occurring in this period. Recurrence was associated with major TT pre-operatively (OR 2.39, 95% CI 1.83–3.11), pre-operative entropic lashes compared to misdirected/metaplastic lashes (OR 1.99, 95% CI 1.23–3.20), age over 40 years (OR 1.59, 95% CI 1.14–2.20) and specific surgeons (surgeon recurrence risk range: 18%–53%). Granuloma occurred in 69 (5.7%) and notching in 156 (13.0%). Conclusions/Significance Risk of recurrence is high despite high volume, highly trained surgeons. However, the vast majority are minor recurrences, which may not have significant corneal or visual consequences. Inter-surgeon variation in recurrence is concerning; surgical technique, training and immediate post-operative lid position require further investigation. Trachoma is the most common infectious cause of blindness worldwide. It causes trichiasis (inturning of the eyelashes to touch the eye), which can cause visual loss. Trachomatous trichiasis (TT) affects over eight million people, 1.2 of whom live in Ethiopia – the most affected country worldwide. Surgery is the mainstay of treatment for TT. However, results of surgery in the field are often very mixed. We investigated the surgical outcomes of one of the two most widely used surgical techniques (posterior lamellar rotation), in 1300 individuals in the Amhara Region of Ethiopia. We found that recurrence occurred frequently: 315/1276 (24.7%) participants. However, recurrence was rarely severe (greater than 5 lashes): 42 participants (3.3%). Recurrence occurred much more frequently in participants who had severe pre-operative disease and with specific surgeons. The high recurrence rates and inter-surgeon variation is concerning. Further research will be required to investigate factors such as surgical technique, surgeon training and immediate post-operative lid position, in order to improve surgical outcomes.
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Affiliation(s)
- Saul N Rajak
- The London School of Hygiene and Tropical Medicine, London, United Kingdom.
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Burr SE, Hart JD, Edwards T, Baldeh I, Bojang E, Harding-Esch EM, Holland MJ, Lietman TM, West SK, Mabey DCW, Sillah A, Bailey RL. Association between ocular bacterial carriage and follicular trachoma following mass azithromycin distribution in The Gambia. PLoS Negl Trop Dis 2013; 7:e2347. [PMID: 23936573 PMCID: PMC3723595 DOI: 10.1371/journal.pntd.0002347] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 06/19/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Trachoma, caused by ocular Chlamydia trachomatis infection, is the leading infectious cause of blindness, but its prevalence is now falling in many countries. As the prevalence falls, an increasing proportion of individuals with clinical signs of follicular trachoma (TF) is not infected with C. trachomatis. A recent study in Tanzania suggested that other bacteria may play a role in the persistence of these clinical signs. METHODOLOGY/PRINCIPAL FINDINGS We examined associations between clinical signs of TF and ocular colonization with four pathogens commonly found in the nasopharnyx, three years after the initiation of mass azithromycin distribution. Children aged 0 to 5 years were randomly selected from 16 Gambian communities. Both eyes of each child were examined and graded for trachoma according to the World Health Organization (WHO) simplified system. Two swabs were taken from the right eye: one swab was processed for polymerase chain reaction (PCR) using the Amplicor test for detection of C. trachomatis DNA and the second swab was processed by routine bacteriology to assay for the presence of viable Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus and Moraxella catarrhalis. Prevalence of TF was 6.2% (96/1538) while prevalence of ocular C. trachomatis infection was 1.0% (16/1538). After adjustment, increased odds of TF were observed in the presence of C. trachomatis (OR = 10.4, 95%CI 1.32-81.2, p = 0.03), S. pneumoniae (OR = 2.14, 95%CI 1.03-4.44, p = 0.04) and H. influenzae (OR = 4.72, 95% CI 1.53-14.5, p = 0.01). CONCLUSIONS/SIGNIFICANCE Clinical signs of TF can persist in communities even when ocular C. trachomatis infection has been controlled through mass azithromycin distribution. In these settings, TF may be associated with ocular colonization with bacteria commonly carried in the nasopharnyx. This may affect the interpretation of impact surveys and the determinations of thresholds for discontinuing mass drug administration.
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Affiliation(s)
- Sarah E Burr
- Department of Clinical Research, Faculty of Infectious and Tropical Disease, London School of Hygiene and Tropical Medicine, London, United Kingdom.
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Lavett DK, Lansingh VC, Carter MJ, Eckert KA, Silva JC. Will the SAFE strategy be sufficient to eliminate trachoma by 2020? Puzzlements and possible solutions. ScientificWorldJournal 2013; 2013:648106. [PMID: 23766701 PMCID: PMC3671555 DOI: 10.1155/2013/648106] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 03/13/2013] [Indexed: 11/18/2022] Open
Abstract
Since the inception of (the Global Elimination of Blinding Trachoma) GET 2020 in 1997 and the implementation of the SAFE strategy a year later, much progress has been made toward lowering the prevalence of trachoma worldwide with elimination of the disease in some countries. However, high recurrence of trichiasis after surgery, difficulty in controlling the reemergence of infection after mass distribution of azithromycin in some communities, the incomplete understanding of environment in relation to the disease, and the difficulty in establishing the prevalence of the disease in low endemic areas are some of the issues still facing completion of the GET 2020 goals. In this narrative review, literature was searched from 1998 to January 2013 in PubMed for original studies and reviews. Reasons for these ongoing problems are discussed, and several suggestions are made as avenues for exploration in relation to improving the SAFE strategy with emphasis on improving surgical quality and management of the mass treatment with antibiotics. In addition, more research needs to be done to better understand the approach to improve sanitation, hygiene, and environment. The main conclusion of this review is that scale-up is needed for all SAFE components, and more research should be generated from communities outside of Africa and Asia.
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Affiliation(s)
- Diane K. Lavett
- Strategic Solutions, Inc., 1143 Salsbury Avenue, Cody, WY 82414, USA
| | - Van C. Lansingh
- International Agency for the Prevention of Blindness/VISION 2020 Latin America, 3720 San Simeon Circle, Weston, FL 33331, USA
- Hamilton Eye Institute, University of Memphis, Memphis, TN 38152, USA
| | - Marissa J. Carter
- Strategic Solutions, Inc., 1143 Salsbury Avenue, Cody, WY 82414, USA
| | - Kristen A. Eckert
- Strategic Solutions, Inc., 1143 Salsbury Avenue, Cody, WY 82414, USA
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Abstract
PURPOSE OF REVIEW To review recent clinical and epidemiological studies regarding the prevention, diagnosis, and treatment of trachoma. RECENT FINDINGS Newer studies propose novel diagnostic tests that appear sensitive for the detection of ocular chlamydial infection. For example, recent studies with ribosomal RNA-based nucleic acid amplification tests (NAATs) have demonstrated improved sensitivities compared to DNA-based NAATs; and the progression of scarring has now been characterized with confocal microscopy. Immunologic studies have further explored the etiology of clinical sequelae, suggesting that chronic inflammation can lead to progressive scarring even in the absence of Chlamydia. Mass oral azithromycin distributions remain a mainstay of treatment; studies have assessed the appropriate frequency and duration of treatment programs. Current studies have also explored ancillary effects of azithromycin distribution on mortality and bacterial infections. SUMMARY Trachoma programs have had remarkable success at reducing chlamydial infection and clinical signs of trachoma. Recent work suggests improved methods to monitor infection and scarring, and better ways to distribute treatment. Whereas studies continue to demonstrate reduction in infection in hyperendemic areas, more work is necessary to achieve elimination of this blinding disease.
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Abstract
Trachoma, caused by Chlamydia trachomatis (Ct), is the leading infectious blinding disease worldwide. Chronic conjunctival inflammation develops in childhood and leads to eyelid scarring and blindness in adulthood. The immune response to Ct provides only partial protection against re-infection, which can be frequent. Moreover, the immune response is central to the development of scarring pathology, leading to loss of vision. Here we review the current literature on both protective and pathological immune responses in trachoma. The resolution of Ct infection in animal models is IFNγ-dependent, involving Th1 cells, but whether this is the case in human ocular infection still needs to be confirmed. An increasing number of studies indicate that innate immune responses arising from the epithelium and other innate immune cells, along with changes in matrix metalloproteinase activity, are important in the development of tissue damage and scarring. Current trachoma control measures, which are centred on repeated mass antibiotic treatment of populations, are logistically challenging and have the potential to drive antimicrobial resistance. A trachoma vaccine would offer significant advantages. However, limited understanding of the mechanisms of both protective immunity and immunopathology to Ct remain barriers to vaccine development.
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Burton MJ, Rajak SN, Ramadhani A, Weiss HA, Habtamu E, Abera B, Emerson PM, Khaw PT, Mabey DCW, Holland MJ, Bailey RL. Post-operative recurrent trachomatous trichiasis is associated with increased conjunctival expression of S100A7 (psoriasin). PLoS Negl Trop Dis 2012; 6:e1985. [PMID: 23285311 PMCID: PMC3527350 DOI: 10.1371/journal.pntd.0001985] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 11/12/2012] [Indexed: 01/17/2023] Open
Abstract
Background Surgery for trachomatous trichiasis (TT) is a key component of the SAFE Strategy for trachoma control. Unfortunately, recurrent TT following surgery is common, probably due to various surgical and disease factors. To develop strategies to reduce recurrence rates it is necessary to understand its pathological basis. In this study we investigated the relationship between recurrent trichiasis and the expression of various cytokines and fibrogenic genes during a two-year follow-up period. Methodology/Principal Findings Individuals undergoing surgery for TT were examined at baseline (pre-operative), 6, 12, 18 and 24 months. Conjunctival swab samples were collected from the tarsal conjunctiva for RNA isolation on each occasion. Individuals who developed recurrent TT with at least 3 lashes touching the eye on one or more occasion were designated “cases” and an equal number of “controls” were randomly selected from those without recurrent TT, frequency matched for age and baseline TT severity. The expression of the following genes was measured by quantitative RT-PCR: S100A7, IL1B, CXCL5, TNFA, NOS2A, CTGF, MMP7, MMP9 and MMP12. Thirteen hundred individuals were enrolled and underwent surgery. By two years 122 had developed recurrent TT with at least 3 lashes touching the eye. Recurrent TT was consistently associated across multiple time points with about a 2-fold increase in S100A7 expression (p = 0.008). Clinically visible conjunctival inflammation was associated with increased S100A7, IL1B, CXCL5, MMP9 and MMP12 expression. Conclusions/Significance Increased S100A7 expression was associated with trachomatous conjunctival scarring and may be linked to the pathophysiology of recurrent TT. S100A7 expression could be a potential biomarker for this disease process. As part of the epithelial innate immune response S100A7 has multiple actions, potentially contributing to a chronic pro-inflammatory response, which may lead to ongoing tissue damage and increased scarring. Trachoma causes blindness through corneal damage from in-turned eyelashes (trachomatous trichiasis [TT]). Trichiasis is treated surgically to correct the anatomical abnormality. Unfortunately, TT frequently returns following surgery, which again puts the person at risk of sight loss. Recurrent trichiasis is multifactorial. We investigated the possible role of various immuno-fibrogenic factors. To do this we operated on 1300 people with TT and followed them up every six months for a two-year period. On each occasion a conjunctival swab was collected for human gene expression analysis. We measured various factors that are thought to be important in inflammation and scarring diseases. The gene expression profile of people who developed recurrent TT was compared to a sample of those that did not have a recurrence. Recurrent TT was associated with increased expression of psoriasin (S100A7) before surgery and on multiple occasions during a two-year follow-up period. S100A7 is able to promote inflammation and may contribute to the development of the scarring process in trachoma.
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Affiliation(s)
- Matthew J Burton
- London School of Hygiene and Tropical Medicine, London, United Kingdom.
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Khanduja S, Jhanji V, Sharma N, Vashist P, Murthy GVS, Gupta SK, Satpathy G, Tandon R, Titiyal JS, Vajpayee RB. Trachoma prevalence in women living in rural northern India: rapid assessment findings. Ophthalmic Epidemiol 2012; 19:216-20. [PMID: 22775277 DOI: 10.3109/09286586.2012.657765] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE Rapid assessment of cicatricial trachoma in adult females aged over 15 years in a previously hyperendemic rural area in Haryana, North India. METHODS Ten disadvantaged villages each with a population of 3000-5000 were chosen by cluster random sampling. One thousand females, 500 between 15-30 years and the rest over 30 years in the underdeveloped parts of the villages, identified by observation and consultation, were examined for signs of trachomatous scarring (TS), trachomatous trichiasis (TT) and trachomatous corneal opacity (TCO). Examinations of both eyes were performed with the aid of a binocular loupe (2.5x magnification) for signs of trachoma, its complications and other ocular morbidities. RESULTS Bilateral examination was carried out in all participants. About two-thirds (n = 650; 65%) of subjects did not have any signs of trachoma. The percentages of trachoma stages TS, TT and TCO were found to be 26.4%, 5.4% and 3.2% respectively. Trichiasis was observed in 54 subjects, all in the age group >30 years, and highest in the age group 66-75 years (22.8%). Females in the age group >30 years had significantly higher cicatricial trachoma compared to females <30 years (p < 0.001). Overall 59.3% of affected females had not received any treatment. Epilation and entropion surgery had been performed in 30.3% and 10.4% of affected females, respectively. CONCLUSION The results of our rapid assessment suggest that the presence of cicatricial trachoma remains an important health issue in females over 15 years of age.
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Affiliation(s)
- Sumeet Khanduja
- Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
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Cevallos V, Whitcher JP, Melese M, Alemayehu W, Yi E, Chidambaram JD, Lee S, Reddy H, Gaynor BD, Lietman TM, Keenan JD. Association of conjunctival bacterial infection and female sex in cicatricial trachoma. Invest Ophthalmol Vis Sci 2012; 53:5208-12. [PMID: 22736616 DOI: 10.1167/iovs.12-9984] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
PURPOSE Conjunctival infection with non-chlamydial bacteria may play an important role in the progression of trachoma, especially with regard to the development of corneal opacity and blindness. To further characterize the microbiological profile of bacterial conjunctival infections in cicatricial trachoma, a conjunctival swabbing of adults in rural Ethiopia was performed. METHODS In a cross-sectional study conducted in nine Ethiopian villages with hyperendemic trachoma, persons 40 years of age or older with signs or symptoms consistent with trichiasis were recruited and conjunctival swabbing for bacterial pathogens was performed. RESULTS Conjunctival examination and swabbing on 112 females and 36 males were performed. Of the 148 study participants, 101 (68.2%) were confirmed to have trichiasis, and 118 (80%) had conjunctival swabs positive for bacteria. In multivariate analyses, growth of pathogenic conjunctival bacteria was independently associated with trichiasis (odds ratio [OR] 6.93; 95% confidence interval [CI] 2.71-17.7) and female sex (OR 5.90; 95% CI 2.09-16.7). Females were more likely to have swabs positive for Streptococcus pneumoniae or Haemophilus influenzae than were males (OR 9.09; 95% CI 1.17-70.8). CONCLUSIONS In a region of Ethiopia with endemic trachoma, conjunctival bacterial growth was more common in females than that in males. S. pneumoniae and H. influenzae, both of which frequently colonize the nasopharynx of children, were more common in females, suggesting that the preponderance of infection in females may be attributable to close contact with children. This finding is consistent with the theory that childcare activities may preferentially expose females to ocular chlamydial infection. (ClinicalTrials.gov number, NCT00221364.).
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Affiliation(s)
- Vicky Cevallos
- Francis I. Proctor Foundation, San Francisco, California 94143-0412, USA
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Gower EW, West SK, Cassard SD, Munoz BE, Harding JC, Merbs SL. Definitions and standardization of a new grading scheme for eyelid contour abnormalities after trichiasis surgery. PLoS Negl Trop Dis 2012; 6:e1713. [PMID: 22745845 PMCID: PMC3383763 DOI: 10.1371/journal.pntd.0001713] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2012] [Accepted: 05/15/2012] [Indexed: 11/28/2022] Open
Abstract
Background Clear definitions of outcomes following trichiasis surgery are critical for planning program evaluations and for identifying ways to improve trichiasis surgery. Eyelid contour abnormality is an important adverse outcome of surgery; however, no standard method has been described to categorize eyelid contour abnormalities. Methodology/Principal Findings A classification system for eyelid contour abnormalities following surgery for trachomatous trichiasis was developed. To determine whether the grading was reproducible using the classification system, six-week postoperative photographs were reviewed by two senior graders to characterize severity of contour abnormalities. Sample photographs defining each contour abnormality category were compiled and used to train four new graders. All six graders independently graded a Standardization Set of 75 eyelids, which included a roughly equal distribution across the severity scale, and weighted kappa scores were calculated. Two hundred forty six-week postoperative photographs from an ongoing clinical trial were randomly selected for evaluating agreement across graders. Two months after initial grading, one grader regraded a subset of the 240 photographs to measure longer-term intra-observer agreement. The weighted kappa for agreement between the two senior graders was 0.80 (95% CI: 0.71–0.89). Among the Standardization Set, agreement between the senior graders and the 4 new graders showed weighted kappa scores ranging from 0.60–0.80. Among 240 eyes comprising the clinical trial dataset, agreement ranged from weighted kappa 0.70–0.71. Longer-term intra-observer agreement was weighted kappa 0.86 (95% CI: 0.80–0.92). Conclusions/Significance The standard eyelid contour grading system we developed reproducibly delineates differing levels of contour abnormality. This grading system could be useful both for helping to evaluate trichiasis surgery outcomes in clinical trials and for evaluating trichiasis surgery programs. Approximately 8 million individuals worldwide suffer from trichiasis, a condition characterized by in-turned lashes that rub against the eye. Trichiasis is caused by repeated or prolonged ocular infection with Chlamydia trachomatis. Surgery is available to correct in-turned lashes. In most programmatic and research settings, the primary determinant of surgical success is whether or not lashes are touching the globe post-operatively. However, other surgical outcomes such as the contour of the eyelid are also important. Yet, no standard method for evaluating and reporting this outcome has been defined. In this study, we developed and tested a grading system for evaluating the severity of eyelid contour abnormalities after surgery using photographs of eyelids six weeks post-operatively. We found good agreement across photograph graders and also between field and photograph grades. This system should be useful in helping to standardize reporting of this outcome.
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Affiliation(s)
- Emily W Gower
- Department of Epidemiology and Prevention, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America.
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Trachomatous trichiasis and its management in endemic countries. Surv Ophthalmol 2012; 57:105-35. [PMID: 22285842 PMCID: PMC3316859 DOI: 10.1016/j.survophthal.2011.08.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 08/09/2011] [Accepted: 08/11/2011] [Indexed: 11/20/2022]
Abstract
Trichiasis is the sight-threatening consequence of conjunctival scarring in trachoma, the most common infectious cause of blindness worldwide. Trachomatous trichiasis is the result of multiple infections from childhood with Chlamydia trachomatis, which causes recurrent chronic inflammation in the tarsal conjunctiva. This produces conjunctival scarring, entropion, trichiasis, and ultimately blinding corneal opacification. The disease causes painful, usually irreversible sight loss. Over eight million people have trachomatous trichiasis, mostly those living in poor rural communities in 57 endemic countries. The global cost is estimated at US$ 5.3 billion. The WHO recommends surgery as part of the SAFE strategy for controlling the disease.We examine the principles of clinical management, treatment options, and the challenging issues of providing the quantity and quality of surgery that is needed in resource-poor settings.
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Chen H, Wu X, Wei M, Eichner JE, Fan Y, Zhang Z, Lei C, Stone DU, Yang J. Changes in the prevalence of visual impairment due to blinding trachoma in Sichuan province, China: a comparative study between 1987 and 2006. Ophthalmic Epidemiol 2011; 19:29-37. [PMID: 22168755 DOI: 10.3109/09286586.2011.615451] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE The aim of this study was to assess the changes in the prevalence of visual impairment due to blinding trachoma in Sichuan, China between 1987 and 2006. METHODS Over 125,000 residents of Sichuan province participated in the National Sample Survey on Disabilities, conducted in both 1987 and 2006. Changes in the prevalence of visual impairment due to blinding trachoma were analyzed while accounting for other factors including gender, age and residence (urban vs. rural). RESULTS In 1987, blinding trachoma ranked second among the eight major visual impairment causes assessed with a prevalence of 172.9 (95% CI: 152.2-196.6) per 100,000, while in 2006 it ranked eighth with a prevalence of 58.1 (95% CI: 45.5-73.0) per 100,000. The prevalence in 2006 decreased significantly compared to 1987 in both rural and urban areas, as well as in both genders. Furthermore, in both 1987 and 2006, visual impairment due to blinding trachoma tended to be concentrated among individuals over 40, although it was also seen in young people. CONCLUSION In the past 20 years, the prevalence and percentage of visual impairment due to blinding trachoma was significantly reduced in Sichuan province, and we anticipate a further decrease in the future.
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Affiliation(s)
- Hui Chen
- Ophthalmology Department, Sichuan Provincial People's Hospital & Sichuan Academy of Medical Sciences, Chengdu, Sichuan, China
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Woreta F, Munoz B, Gower E, Alemayehu W, West SK. Three-year outcomes of the surgery for trichiasis, antibiotics to prevent recurrence trial. ACTA ACUST UNITED AC 2011; 130:427-31. [PMID: 22159169 DOI: 10.1001/archophthalmol.2011.374] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To determine whether treatment with oral azithromycin compared with topical tetracycline reduces the recurrence of trichiasis for up to 3 years following surgery for trichiasis. METHODS The Surgery for Trichiasis, Antibiotics to Prevent Recurrence (STAR) trial is a randomized, single-masked, clinical trial conducted in southern Ethiopia, a region where trachoma is hyperendemic. A total of 1452 patients who underwent trichiasis surgery were randomly assigned at a 2:1 ratio to either a single dose of oral azithromycin (1 g) or topical tetracycline (twice per day for 6 weeks) following surgery. MAIN OUTCOME MEASURES Recurrence of trichiasis within 3 years following surgery. RESULTS The rate of recurrence was 10% in the azithromycin group and 13% in the tetracycline group. The azithromycin group had a 22% reduction in recurrence of trichiasis 3 years after surgery compared with the tetracycline group (P = .13). Severity of entropion at baseline was the most significant predictor of recurrence of trichiasis at 3 years. CONCLUSION Trichiasis recurrence rates in the STAR trial remained low for up to 3 years following surgery. The protective effect of a single dose of azithromycin was less than at 1 year and, although not statistically significant, was still suggestive up to 3 years following trichiasis surgery. APPLICATION TO CLINICAL PRACTICE A single dose of azithromycin after surgery remains an integral component of the World Health Organization's strategy for the elimination of trachoma by the year 2020.
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Affiliation(s)
- Fasika Woreta
- Dana Center for Preventive Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, 600 N Wolfe St, Baltimore, MD 21287, USA
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Rajak SN, Habtamu E, Weiss HA, Kello AB, Gebre T, Genet A, Bailey RL, Mabey DCW, Khaw PT, Gilbert CE, Emerson PM, Burton MJ. Absorbable versus silk sutures for surgical treatment of trachomatous trichiasis in Ethiopia: a randomised controlled trial. PLoS Med 2011; 8:e1001137. [PMID: 22180732 PMCID: PMC3236737 DOI: 10.1371/journal.pmed.1001137] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2011] [Accepted: 10/19/2011] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Trachoma causes blindness through an anatomical abnormality called trichiasis (lashes touching the eye). Trichiasis can recur after corrective surgery. We tested the hypothesis that using absorbable sutures instead of silk sutures might reduce the risk of recurrent disease among patients with major trichiasis in a randomised trial. METHODS AND FINDINGS 1,300 individuals with major trichiasis from rural villages in the Amhara Region of Ethiopia were recruited and assigned (1:1) by computer-generated randomisation sequence to receive trichiasis surgery using either an absorbable suture (polyglactin-910) or silk sutures (removed at 7-10 days) in an otherwise identical surgical technique. Participants were examined every 6 months for 2 years by clinicians masked to allocation. The primary outcome measure was recurrent trichiasis (≥one lash touching the eye) at 1 year. There was no difference in prevalence of recurrent trichiasis at 1 year (114 [18.2%] in the absorbable suture group versus 120 [19.7%] in the silk suture group; odds ratio = 0.90, 95% CI 0.68-1.20). The two groups also did not differ in terms of corneal opacification, visual acuity, conjunctival inflammation, and surgical complications. CONCLUSIONS There was no evidence that use of absorbable polyglactin-910 sutures was associated with a lower prevalence of trichiasis recurrence at 1 year postsurgery than silk sutures. However, from a programmatic perspective, polyglactin-910 offers the major advantage that patients do not have to be seen soon after surgery for suture removal. The postoperative review after surgery using absorbable polyglactin-910 sutures can be delayed for 3-6 months, which might allow us to better determine whether a patient needs additional surgery. TRIAL REGISTRATION ClinicalTrials.gov NCT00522860.
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Affiliation(s)
- Saul N. Rajak
- The London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Helen A. Weiss
- The London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | - Asrat Genet
- The Amhara Regional Health Bureau, Bahir Dar, Ethiopia
| | - Robin L. Bailey
- The London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - David C. W. Mabey
- The London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Peng T. Khaw
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital and UCL Institute of Ophthalmology and UCL Partners AHSC, London, United Kingdom
| | - Clare E. Gilbert
- The London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Matthew J. Burton
- The London School of Hygiene and Tropical Medicine, London, United Kingdom
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital and UCL Institute of Ophthalmology and UCL Partners AHSC, London, United Kingdom
- * E-mail:
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