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Alreshidi SO, Vargas JM, Ahmad K, Alothman AY, Albalawi ED, Almulhim A, Alenezi SH, ALBalawi HB, Alali NM, Hashem F, Aljindan M. Differentiation of acanthamoeba keratitis from other non-acanthamoeba keratitis: Risk factors and clinical features. PLoS One 2024; 19:e0299492. [PMID: 38470877 DOI: 10.1371/journal.pone.0299492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/11/2024] [Indexed: 03/14/2024] Open
Abstract
INTRODUCTION Infectious Keratitis is one of the most common ocular emergencies seen by ophthalmologists. Our aim is to identify the risk factors and clinical features of Acanthamoeba Keratitis (AK). METHODS This retrospective chart review study was conducted at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia, and included all the microbial keratitis cases, male and female patients of all ages. The main outcome is the differentiation between various microbial keratitis types. RESULTS We included 134 consecutive eyes of 126 persons. We had 24 cases of acanthamoeba keratitis, 22 bacterial keratitis, 24 fungal keratitis, 32 herpetic keratitis, and 32 bacterial co-infection. Contact lens wear was found in 33 eyes (24.6%). Among acanthamoeba keratitis patients, 73% were ≤ 39 years of age, and 73% were females (P <0.001). Also, in AK cases, epithelial defect was found in all cases (100%), endothelial plaques were found in 18 eyes (69.2%), 12 cases had radial keratoneuritis (46.2%), and ring infiltrate was found in 53.8% of AK cases. CONCLUSIONS We determined the factors that increase the risk of acanthamoeba infection and the clinical characteristics that help distinguish it from other types of microbial keratitis. Our findings suggest that younger females and patients who wear contact lenses are more likely to develop acanthamoeba keratitis. The occurrence of epitheliopathy, ring infiltrate, radial keratoneuritis, and endothelial plaques indicate the possibility of acanthamoeba infection. Promoting education on wearing contact lenses is essential to reduce the risk of acanthamoeba infection, as it is the most significant risk factor for this infection.
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Affiliation(s)
| | - José Manuel Vargas
- Cornea, External Diseases Section, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Ophthalmology Division, King Abdullah Bin Abdulaziz University Hospital, Riyadh, Saudi Arabia
| | - Khabir Ahmad
- Research Department, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Ahmed Yousef Alothman
- Ophthalmology Department, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Eman D Albalawi
- Clinical Sciences Department, College of Medicine, Princess Noura Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Abdulmohsen Almulhim
- Department of Ophthalmology, College of Medicine, Jouf University, Sakakah, Saudi Arabia
| | - Saad Hamdan Alenezi
- Ophthalmology Department, College of Medicine, Majmaah University, Majmaah, Saudi Arabia
| | - Hani Basher ALBalawi
- Department of Surgery, Division of Ophthalmology, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia
| | - Naif Mamdouh Alali
- Department of Surgery, Division of Ophthalmology, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia
| | - Faris Hashem
- Department of Surgery, Division of Ophthalmology, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia
| | - Mohanna Aljindan
- Ophthalmology Department, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
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Ilyas M, Stapleton F, Willcox MDP, Henriquez F, Peguda HK, Rayamajhee B, Zahid T, Petsoglou C, Carnt NA. Epidemiology of and Genetic Factors Associated with Acanthamoeba Keratitis. Pathogens 2024; 13:142. [PMID: 38392880 PMCID: PMC10892102 DOI: 10.3390/pathogens13020142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 01/14/2024] [Accepted: 01/31/2024] [Indexed: 02/25/2024] Open
Abstract
Acanthamoeba keratitis (AK) is a severe, rare protozoal infection of the cornea. Acanthamoeba can survive in diverse habitats and at extreme temperatures. AK is mostly seen in contact lens wearers whose lenses have become contaminated or who have a history of water exposure, and in those without contact lens wear who have experienced recent eye trauma involving contaminated soil or water. Infection usually results in severe eye pain, photophobia, inflammation, and corneal epithelial defects. The pathophysiology of this infection is multifactorial, including the production of cytotoxic proteases by Acanthamoeba that degrades the corneal epithelial basement membrane and induces the death of ocular surface cells, resulting in degradation of the collagen-rich corneal stroma. AK can be prevented by avoiding risk factors, which includes avoiding water contact, such as swimming or showering in contact lenses, and wearing protective goggles when working on the land. AK is mostly treated with an antimicrobial therapy of biguanides alone or in combination with diaminidines, although the commercial availability of these medicines is variable. Other than anti-amoeba therapies, targeting host immune pathways in Acanthamoeba disease may lead to the development of vaccines or antibody therapeutics which could transform the management of AK.
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Affiliation(s)
- Muhammad Ilyas
- Primary & Secondary Healthcare Department, Punjab 54000, Pakistan; (M.I.)
| | - Fiona Stapleton
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Mark D. P. Willcox
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Fiona Henriquez
- School of Health and Life Sciences, The University of the West of Scotland, Glasgow G72 0LH, UK
| | - Hari Kumar Peguda
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Binod Rayamajhee
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
| | - Tasbiha Zahid
- Primary & Secondary Healthcare Department, Punjab 54000, Pakistan; (M.I.)
| | | | - Nicole A. Carnt
- School of Optometry and Vision Science, University of NSW, Sydney, NSW 2052, Australia (H.K.P.)
- Centre for Vision Research, Westmead Institute for Medical Research, Sydney, NSW 2145, Australia
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Wang Y, Jiang L, Zhao Y, Ju X, Wang L, Jin L, Fine RD, Li M. Biological characteristics and pathogenicity of Acanthamoeba. Front Microbiol 2023; 14:1147077. [PMID: 37089530 PMCID: PMC10113681 DOI: 10.3389/fmicb.2023.1147077] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 03/21/2023] [Indexed: 04/25/2023] Open
Abstract
Acanthamoeba is an opportunistic protozoa, which exists widely in nature and is mainly distributed in soil and water. Acanthamoeba usually exists in two forms, trophozoites and cysts. The trophozoite stage is one of growth and reproduction while the cyst stage is characterized by cellular quiescence, commonly resulting in human infection, and the lack of effective monotherapy after initial infection leads to chronic disease. Acanthamoeba can infect several human body tissues such as the skin, cornea, conjunctiva, respiratory tract, and reproductive tract, especially when the tissue barriers are damaged. Furthermore, serious infections can cause Acanthamoeba keratitis, granulomatous amoebic encephalitis, skin, and lung infections. With an increasing number of Acanthamoeba infections in recent years, the pathogenicity of Acanthamoeba is becoming more relevant to mainstream clinical care. This review article will describe the etiological characteristics of Acanthamoeba infection in detail from the aspects of biological characteristic, classification, disease, and pathogenic mechanism in order to provide scientific basis for the diagnosis, treatment, and prevention of Acanthamoeba infection.
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Affiliation(s)
- Yuehua Wang
- College of Laboratory Medicine, Jilin Medical University, Jilin City, China
| | - Linzhe Jiang
- General Surgery, Jilin People’s Hospital, Jilin City, China
| | - Yitong Zhao
- College of Laboratory Medicine, Jilin Medical University, Jilin City, China
| | - Xiaohong Ju
- College of Laboratory Medicine, Jilin Medical University, Jilin City, China
| | - Le Wang
- Department of Laboratory Medicine, Jilin Hospital of Integrated Chinese and Western Medicine, Jilin City, China
| | - Liang Jin
- Department of Laboratory Medicine, Jilin Hospital of Integrated Chinese and Western Medicine, Jilin City, China
| | - Ryan D. Fine
- Center for Human Genetics and Genomics, New York University Grossman School of Medicine, New York City, NY, United States
| | - Mingguang Li
- College of Laboratory Medicine, Jilin Medical University, Jilin City, China
- *Correspondence: Mingguang Li,
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Kasparova EA, Marchenko NR, Surnina ZV, Mitichkina TS. [Confocal microscopy in the diagnosis of acanthamoeba keratitis]. Vestn Oftalmol 2021; 137:201-208. [PMID: 34669328 DOI: 10.17116/oftalma2021137052201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Acanthamoeba keratitis (AK) is a dangerous disease of the cornea, its prevalence has increased significantly due to widespread usage of contact lenses. The similarity of the clinical manifestations of AK to other infectious keratitis (especially herpetic keratitis) requires introduction of a rapid diagnosis method into clinical practice. PURPOSE To evaluate the capabilities of corneal confocal microscopy (CCM) in the diagnosis of acanthamoeba keratitis. MATERIAL AND METHODS We examined 33 patients (35 eyes) with suspected acanthamoeba keratitis using light and laser confocal microscopy of the cornea (ConfoScan and HRT devices, respectively). RESULTS CCM was technically feasible in 23 of 35 cases (65.7%). Acanthamoeba cysts were detected in 16 cases (69.6%); trophozoites were visualized in 17.4% of cases; signs of keratoneuritis were detected in 12 eyes (52.2%); in 7 cases (30.4%), hyporeflective honeycomb-like cavities were observed in the stroma; deep stromal striae were observed in 9 cases (39.1%); activated keratocytes were detected in 11 patients (47.8%), and Langerhans cells were detected in 19 cases (82.6%). CONCLUSIONS The main diagnostic value of confocal microscopy is the detection of direct markers of AK - cysts and trophozoites of Acanthamoeba. Both light and laser CCM techniques are suitable for the diagnosis of AK, but the resolution of laser confocal microscopy is higher. The non-invasive nature of this method and the possibility of multiple subsequent examinations make it possible to verify the diagnosis of acanthamoeba keratitis and monitor the treatment.
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Affiliation(s)
| | | | - Z V Surnina
- Research Institute of Eye Diseases, Moscow, Russia
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Acanthamoeba Keratitis Versus Mixed Acanthamoeba and Bacterial Keratitis: Comparison of Clinical and Microbiological Profiles. Cornea 2021; 39:1112-1116. [PMID: 32452992 DOI: 10.1097/ico.0000000000002337] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To compare the clinical profiles and outcomes of patients with Acanthamoeba keratitis with or without mixed bacterial infection. METHODS A retrospective analysis of microbiologically confirmed AK cases presenting to a tertiary care center over a 9-year period was conducted. Fourteen eyes in the coinfected group (group 1) and 24 eyes in the AK group (group 2) were analyzed to study the differences in these 2 groups of patients. The cases were diagnosed using a conventional microscopic analysis with staining techniques confirmed by cultural methods and were treated, which tailored to the microbiology report. RESULTS There was no difference in the demographic profile and presenting features in the 2 groups. Duration of symptoms and history of ocular trauma, contact lens wear, and previous steroid usage were also similar for both the groups. Dense central corneal infiltrate was the common presentation for both groups (7/14 vs. 16/24 in group 1 vs. group 2). Epithelial defect without dense stromal infiltrate was significantly more common in group 1 (42.9% vs. 4.2%, P = 0.003) as a presenting clinical feature. Hypopyon was present in 8/14 of group 1 versus 9/24 of group 2 eyes (P = 0.25). No significant difference was found in the final visual acuity in pure and mixed AK cases, and the need for surgical intervention was comparable. The most common bacterial pathogen isolated in the mixed group was the Staphylococcus species. CONCLUSIONS Bacterial coinfection is common in patients with Acanthamoeba keratitis. Coinfection did not point toward a worse clinical disease at presentation or outcome.
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Abstract
PURPOSE Voriconazole was shown to inhibit ergosterol synthesis in various acanthamoeba species. The purpose of this study was to evaluate the clinical outcome of treatment with supplemental topical voriconazole in patients with acanthamoeba keratitis (AK). METHODS All patients who had been treated for AK with voriconazole 1% drops in conjunction with topical first-line antiacanthamoeba therapy composed of polyhexamethylene biguanide (PHMB) 0.02% and propamidine isethionate 0.1% (Brolene) between November 2014 and August 2017 at the Department of Ophthalmology, University Medical Center Mainz, were included. The main outcomes were treatment failure and recurrence rate. Secondary outcomes were visual acuity, need for keratoplasty, and presence of adverse reactions. RESULTS Twenty-eight eyes of 28 patients with AK, whose treatment had included topical voriconazole, were identified (12 men, 16 women, mean age: 41.7 ± 16.3 years), and 26 of them could be tracked for at least 3 months after cessation of therapy. Resolution of infection under therapy was seen in all eyes, and only one of 26 (3.85%) had a relapse after the therapy had been stopped. Best-corrected visual acuity improved during therapy. Keratoplasty because of central corneal scarring was scheduled in 5 of 26 patients (19.2%) after the pharmacological therapy had been stopped. Five of 26 patients (19.2%) reported on stinging or burning sensation after application of voriconazole 1% drops. CONCLUSIONS Topical voriconazole 1% combined with first-line therapy composed of polyhexamethylene biguanide 0.02% and propamidine isethionate 0.1% appears to be an effective option with minor side effects for the treatment of AK.
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Evaluation of Acanthamoeba keratitis cases in a tertiary medical care centre over 21 years. Sci Rep 2021; 11:1036. [PMID: 33441799 PMCID: PMC7806847 DOI: 10.1038/s41598-020-80222-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 12/17/2020] [Indexed: 01/29/2023] Open
Abstract
To report on Acanthamoeba keratitis cases in a tertiary university eye-hospital in Graz, Austria, over a 21-year period. Retrospective study. Parameters included demographics, diagnostics, clinical courses, medical therapies, surgical interventions, secondary complications, and best spectacle-corrected visual acuity (BSCVA). Patient records for 44 eyes of 42 patients were analysed; 2 bilateral infections. Mean age at presentation was 31 ± 13 (16-65) years; contact lenses were used in 41 of 44 eyes (93.2%). Symptoms at initial presentation were mainly pain (41/43, 95.3%) and photophobia (16/43, 37.2%). Most frequent morphological findings were stromal infiltrates (30/44, 68.2%). Diagnosis was mainly confirmed by smears (40/42, 95.2%) and polymerase chain reaction (8/42, 19%). Antiamoebic treatment comprised biguanides and diamidines. Penetrating keratoplasty was performed in 10/44 (22.7%) eyes. Median time from symptom onset to initial visit was 2 (0-26) weeks; median follow-up was 30 (2-1008) weeks. BSCVA improved in 23/36 (63.9%) eyes, remained unchanged in 6/36 (16.7%) eyes and deteriorated in 7/36 (19.4%) eyes. Acanthamoeba keratitis predominantly occurs in young contact lens wearers. Diagnosis should be considered in patients with pain and stromal infiltrates. In the majority of cases, BSCVA can be improved. Early diagnosis and adequate treatment should be implemented to prevent complications.
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8
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Lacerda AG, Lira M. Acanthamoeba
keratitis: a review of biology, pathophysiology and epidemiology. Ophthalmic Physiol Opt 2020; 41:116-135. [DOI: 10.1111/opo.12752] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/07/2020] [Accepted: 09/09/2020] [Indexed: 01/13/2023]
Affiliation(s)
| | - Madalena Lira
- Centre of Physics University of Minho Braga Portugal
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Hajialilo E, Rezaeian M, Niyyati M, Pourmand MR, Mohebali M, Norouzi M, Razavi Pashabeyg K, Rezaie S, Khodavaisy S. Molecular characterization of bacterial, viral and fungal endosymbionts of Acanthamoeba isolates in keratitis patients of Iran. Exp Parasitol 2019; 200:48-54. [PMID: 30917916 DOI: 10.1016/j.exppara.2019.03.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 02/18/2019] [Accepted: 03/21/2019] [Indexed: 11/27/2022]
Abstract
Free-living amoebae belong to the genus Acanthamoeba; can feed on microbial population by phagocytosis, and with the capability to act as a reservoir and a vehicle of microorganisms to susceptible host. Therefore, the role of endosymbiosis in the pathogenesis of Acanthamoeba is complex and not fully understood. The aim of the present study was to identify bacterial, fungal, and human adenovirus (HADV) endosymbionts as well as evaluating the endosymbionts role of such organisms in the pathogenesis of Acanthamoeba in keratitis patients living in Iran. Fifteen Acanthamoeba (T4 genotype) isolates were recovered from corneal scrapes and contact lenses of patients with keratitis. Cloning and purification was performed for all isolate. Gram staining was performed to identify bacterial endosymbionts. DNA extraction, PCR, and nested PCR was set up to identify endosymbiont of amoeba. Evaluation of pathogenicity was conducted by osmo-tolerance and thermo-tolerance assays and cell culture, and then CPE (cytopathic effect) was survey. Statistical analysis was used between Acanthamoeba associated endosymbionts and Acanthamoeba without endosymbiont at 24, 48, 72, and 96 h. A p value < 0.05 was considered as significant, statistically. A total of 9 (60%) Acanthamoeba (T4 genotypes) isolates were successfully cloned for detecting microorganism endosymbionts. The only isolate negative for the presence of endosymbiont was ICS9. ICS7 (Pseudomonas aeruginosa, Aspergillus sp., and human adenovirus endosymbionts) and ICS2 (Escherichia coli endosymbiont) isolates were considered as Acanthamoeba associated endosymbionts. ICS7 and ICS2 isolates were highly pathogen whereas ICS9 isolate showed low pathogenicity in pathogenicity evaluated. Positive CPE for ICS7 and ICS2 isolates and negative CPE for ICS9 isolate were observed in cell culture. The average number of cells, trophozoites, and cysts among ICS7, ICS2, and ICS9 isolates at 24, 48, 72, and 96 h was significant. This is the first survey on microbial endosymbionts of Acanthamoeba in keratitis patients of Iran, and also the first report of Aspergillus sp, Achromobacter sp., Microbacterium sp., Brevibacillus sp, Brevundimonas sp and Mastadenovirus sp in Acanthamoeba as endosymbionts. Our study demonstrated that microbial endosymbionts can affect the pathogenicity of Acanthamoeba; however, further research is required to clarify the exact pattern of symbiosis, in order to modify treatment protocol.
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Affiliation(s)
- Elham Hajialilo
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mostafa Rezaeian
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
| | - Maryam Niyyati
- Department of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Mohammad Reza Pourmand
- Department of Pathobiology, School of Public Health, Biotechnology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehdi Mohebali
- Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mehdi Norouzi
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Kobra Razavi Pashabeyg
- Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Sassan Rezaie
- Division of Molecular Biology & Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Sadegh Khodavaisy
- Division of Molecular Biology & Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
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McKelvie J, Alshiakhi M, Ziaei M, Patel DV, McGhee CNJ. The rising tide of Acanthamoeba keratitis in Auckland, New Zealand: a 7-year review of presentation, diagnosis and outcomes (2009-2016). Clin Exp Ophthalmol 2018; 46:600-607. [DOI: 10.1111/ceo.13166] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Revised: 01/01/2018] [Accepted: 01/08/2018] [Indexed: 11/27/2022]
Affiliation(s)
- James McKelvie
- The Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences; University of Auckland; Auckland New Zealand
- The Department of Ophthalmology; Greenlane Clinical Centre, Auckland District Health Board; Auckland New Zealand
| | - Moaz Alshiakhi
- The Department of Ophthalmology; Greenlane Clinical Centre, Auckland District Health Board; Auckland New Zealand
| | - Mohammed Ziaei
- The Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences; University of Auckland; Auckland New Zealand
- The Department of Ophthalmology; Greenlane Clinical Centre, Auckland District Health Board; Auckland New Zealand
| | - Dipika V Patel
- The Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences; University of Auckland; Auckland New Zealand
- The Department of Ophthalmology; Greenlane Clinical Centre, Auckland District Health Board; Auckland New Zealand
| | - Charles NJ McGhee
- The Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences; University of Auckland; Auckland New Zealand
- The Department of Ophthalmology; Greenlane Clinical Centre, Auckland District Health Board; Auckland New Zealand
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Number of Bacteria and Time of Coincubation With Bacteria Required for the Development of Acanthamoeba Keratitis. Cornea 2017; 36:353-357. [DOI: 10.1097/ico.0000000000001129] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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12
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Conjunctivitis, Keratitis and Infections of Periorbital Structures. Infect Dis (Lond) 2017. [DOI: 10.1016/b978-0-7020-6285-8.00016-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Steger B, Speicher L, Philipp W, Gasser T, Schmid E, Bechrakis N. [Effectiveness of initial antibiotic therapy for treatment of contact lens-related bacterial keratitis]. Ophthalmologe 2013; 111:644-8. [PMID: 23948737 DOI: 10.1007/s00347-013-2937-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND Contact lens-related microbial keratitis is a cause of potentially sight-threatening corneal opacification. Effective initial antimicrobial therapy is crucial to prevent long-term complications. This investigation was undertaken to test the effectiveness of current routine empirical antibiotic treatment regimens. METHODS/PATIENTS All consecutive cases of contact lens-related keratitis presenting in the outpatient clinic of the Department of Ophthalmology at the Medical University of Innsbruck between January 2010 and April 2012 were retrospectively analyzed. RESULTS Cultures were positive in 69 out of the 123 cases included in the study. Culture results identified 59.4 % Gram positive strains, 50.7 % Gram negative strains and 7.2 % fungal strains. Mixed infections accounted for 29 % of cases. The combination of an aminoglycoside and a second generation quinolone antibiotic was the most common initial treatment regimen (87.8 %). In vitro this regimen was less effective compared to combinations of moxifloxacin and ciprofloxacin or moxifloxacin and gentamicin. CONCLUSION Empirical combined regimens remain an effective treatment of contact lens-related keratitis. Fluoroquinolones proved to be inadequate for monotherapy.
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Affiliation(s)
- B Steger
- Universitätsklinik für Augenheilkunde und Optometrie, Medizinische Universität Innsbruck, Anichstr. 35, 6020, Innsbruck, Österreich,
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Sharifi N, Botero-Kleiven S, Öhman D, Barragan A, Winiecka-Krusnell J. Genotypic characterization of Acanthamoeba spp. causing ocular infections in Swedish patients: Identification of the T15 genotype in a case of protracted keratitis. ACTA ACUST UNITED AC 2010; 42:781-6. [DOI: 10.3109/00365548.2010.490563] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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15
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Abstract
Acanthamoeba keratitis (AK) is a serious infection of the cornea. At present, diagnosis of the disease is not straightforward and treatment is very demanding. While contact lens wear is the leading risk factor for A K, Acanthamoeba parasites are increasingly recognized as an important cause of keratitis in non-contact lens wearers. The first critical step in the pathogenesis of infection is the adhesion of the microbe to the surface of the host tissues. Acanthamoebae express a major virulence protein, the mannose-binding protein (MBP), which mediates the adhesion of amoebae to the surface of the cornea. The MBP is a transmembrane protein with characteristics of a typical cell surface receptor. Subsequent to the MBP-mediated adhesion to host cells, the amoebae produce a contact-dependent metalloproteinase and several contact-independent serine proteinases. These proteinases work in concert to produce a potent cytopathic effect (CPE ) involving killing of the host cells, degradation of epithelial basement membrane and underlying stromal matrix, and penetration into the deeper layers of the cornea. In the hamster animal model, oral immunization with the recombinant MBP protects against AK, and this protection is associated with an increased level of anti-MBP IgA in tears of protected animals. Normal human tear fluid contains IgA antibodies against Acanthamoeba MBP that is likely to provide protection by inhibiting the adhesion of parasites to host cells. Indeed, in in vitro CPE assays, even a low concentration of tears (10 microL of undiluted tears per milliliter of media) almost completely inhibits Acanthamoeba-induced CPE . In addition to adherence-inhibiting, IgA-mediated protection, human tears also contain IgA-independent factors that provide protection against Acanthamoeba-induced CPE by inhibiting the activity of cytotoxic proteinases. Characterization of the CPE-inhibitory factors of human tears should lead to a better understanding of the mechanism by which the tissues of the host resist the infection and also help decode circumstances that predispose to Acanthamoeba infections.
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Affiliation(s)
- Noorjahan Panjwani
- Departments of Ophthalmology and Biochemistry, The New England Eye Center, Tufts University School of Medicine, Boston, Massachusetts, USA.
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Iovieno A, Ledee DR, Miller D, Alfonso EC. Detection of bacterial endosymbionts in clinical acanthamoeba isolates. Ophthalmology 2010; 117:445-52, 452.e1-3. [PMID: 20031220 DOI: 10.1016/j.ophtha.2009.08.033] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Revised: 08/23/2009] [Accepted: 08/25/2009] [Indexed: 11/30/2022] Open
Abstract
PURPOSE To determine the presence of 4 clinically relevant bacterial endosymbionts in Acanthamoeba isolates obtained from patients with Acanthamoeba keratitis (AK) and the possible contribution of endosymbionts to the pathogenesis of AK. DESIGN Experimental study. PARTICIPANTS Acanthamoeba isolates (N = 37) recovered from the cornea and contact lens paraphernalia of 23 patients with culture-proven AK and 1 environmental isolate. METHODS Acanthamoeba isolates were evaluated for the presence of microbial endosymbionts belonging to the bacterial genera Legionella, Pseudomonas, Mycobacterium, and Chlamydia using molecular techniques (polymerase chain reaction and sequence analysis, fluorescence in situ hybridization) and transmission electron microscopy. Corneal toxicity and virulence of Acanthamoeba isolates with and without endosymbionts were compared using a cytopathic effect (CPE) assay on human corneal epithelial cells in vitro. Initial visual acuity, location and characteristics of the infiltrate, time to detection of the infection, and symptom duration at presentation were evaluated in all patients. MAIN OUTCOME MEASURES Prevalence and potential pathobiology of bacterial endosymbionts detected in Acanthamoeba isolates recovered from AK. RESULTS Twenty-two (59.4%) of the 38 cultures examined contained at least 1 bacterial endosymbiont. One isolate contained 2 endosymbionts, Legionella and Chlamydia, confirmed by fluorescence in situ hybridization. Corneal toxicity (CPE) was significantly higher for Acanthamoeba-hosting endosymbionts compared with isolates without endosymbionts (P<0.05). Corneal pathogenic endosymbionts such as Pseudomonas and Mycobacterium enhanced Acanthamoeba CPE significantly more than Legionella (P<0.05). In the presence of bacterial endosymbionts, there was a trend toward worse initial visual acuity (P>0.05), central location (P<0.05), absence of radial perineuritis (P<0.05), delayed time to detection (P>0.05), and longer symptom duration at presentation (P>0.05). CONCLUSIONS Most Acanthamoeba isolates responsible for AK harbor 1 or more bacterial endosymbionts. The presence of endosymbionts enhances the corneal pathogenicity of Acanthamoeba isolates and may impact detection time and clinical features of AK.
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Affiliation(s)
- Alfonso Iovieno
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami-Miller School of Medicine, Miami, Florida 33136, USA
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Walochnik J, Obwaller A, Gruber F, Mildner M, Tschachler E, Suchomel M, Duchene M, Auer H. Anti-Acanthamoeba efficacy and toxicity of miltefosine in an organotypic skin equivalent. J Antimicrob Chemother 2009; 64:539-45. [DOI: 10.1093/jac/dkp215] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Abstract
PURPOSE The purpose of this study was to assess the incidence and risk factors of Acanthamoeba keratitis (AK) over an 8-year period in a Canadian tertiary care setting. METHODS We retrospectively reviewed the medical records of 41 patients (42 eyes), who were diagnosed as having AK between January 1999 and December 2006 in the cornea clinic at the Toronto Western Hospital. The incidence and risk factors of AK were evaluated. RESULTS The number of cases per year increased from between 0 and 4 in the first 5 years to 9, 14, and 8 in the last 3 years. The annual increasing trend was statistically significant (P = 0.04). The month of onset of disease symptoms showed a trend toward onset in summer and fall and was statistically significant for the difference between January and August (P = 0.0094). The season of onset of disease symptoms showed a trend toward summer onset, and the difference between winter and summer was statistically significant (P = 0.02). 92.9% of cases occurred in contact lens wearers, particularly in soft contact lens wearers (82.1%). CONCLUSIONS The incidence of AK in Canada may be increasing since 2004. There is a seasonal trend toward disease onset in the warmer months.
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Labbé A, Khammari C, Dupas B, Gabison E, Brasnu E, Labetoulle M, Baudouin C. Contribution of In Vivo Confocal Microscopy to the Diagnosis and Management of Infectious Keratitis. Ocul Surf 2009; 7:41-52. [DOI: 10.1016/s1542-0124(12)70291-4] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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