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Orser L, Tran V, O’Byrne P, Kroch A, Bonnetsmueller M, Hasso M, Musten A. Testing for extragenital Neisseria gonorrhoeae and Chlamydia trachomatis: At-home pharyngeal and rectal self-swabs are non-inferior to those completed in healthcare settings. PLoS One 2024; 19:e0302785. [PMID: 38768150 PMCID: PMC11104600 DOI: 10.1371/journal.pone.0302785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 04/12/2024] [Indexed: 05/22/2024] Open
Abstract
INTRODUCTION The rates of gonorrhea and chlamydia have been increasing in the years preceding the COVID19 pandemic. Because most gonorrhea and chlamydia infections are located in the oropharynx and rectum for men who have sex with men (MSM), and because at-home self-collected swabs for these infections are not licensed by Health Canada or the United States Food and Drug Administration, decreased accessed to in-person care during and since the COVID19 pandemic potentially means missed case findings. OBJECTIVES To evaluate the performance of at-home self-collected pharyngeal and rectal swabs for gonorrhea and chlamydia nucleic acid amplification testing. METHODOLOGY All persons who contacted our Sexual Health Clinic and who had a clinical indication to complete oral and/or rectal swabs for gonorrhea and chlamydia were invited to complete at-home swabs in advance of their scheduled appointments. We mailed swabs and instructions to those who consented. Participants brought these swabs to their scheduled in clinic appointments, where we repeated the same swabs. All matching swabs were sent to the laboratory for analysis to determine concordance. RESULTS From September 8, 2022 to July 18, 2023, we enrolled 296 eligible participants who provided 1184 swabs. For analysis, cancelled specimens and specimens with invalid results were excluded, leaving 1032 swabs for comparison. We identified 66 STI diagnoses in 47 unique participants. Overall accuracy was high (exceeding 99%), except for rectal chlamydia, which was 96.0%. While the performance of self-swabs for chlamydia was lower compared to gonorrhea, at-home swabs identified six chlamydia infections that were missed by in-clinic collected swabs (two pharyngeal, four rectal). Removing these six cases as "false positives" increased overall accuracy for chlamydia detection to 99.7% (pharyngeal) and 97.8% (rectal). CONCLUSION Self-collected at-home swabs had good performance acceptable for gonorrhea and chlamydia nucleic acid amplification testing.
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Affiliation(s)
- Lauren Orser
- School of Nursing, University of Ottawa, Ottawa, Ontario, Canada
- Sexual Health Clinic, Ottawa Public Health, Ottawa, Ontario, Canada
| | - Vanessa Tran
- Public Health Ontario, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Patrick O’Byrne
- School of Nursing, University of Ottawa, Ottawa, Ontario, Canada
- Sexual Health Clinic, Ottawa Public Health, Ottawa, Ontario, Canada
| | - Abigail Kroch
- Ontario HIV Treatment Network, Toronto, Ontario, Canada
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
| | | | - Maan Hasso
- Public Health Ontario, Toronto, Ontario, Canada
| | - Alexandra Musten
- School of Nursing, University of Ottawa, Ottawa, Ontario, Canada
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Cachay ER, Gilbert T, Deiss R, Mathews WC. Shared Decision-Making Concerning Anal Cancer Screening in Persons With Human Immunodeficiency Virus. Clin Infect Dis 2023; 76:582-591. [PMID: 35723270 PMCID: PMC10226749 DOI: 10.1093/cid/ciac491] [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: 04/11/2022] [Revised: 05/31/2022] [Accepted: 06/09/2022] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Anal high-grade squamous intraepithelial lesion (aHSIL) is the immediate precursor of anal cancer. Anal cytology is a recommended screening test to identify aHSIL among people with human immunodeficiency virus (HIV; PWH). Heterogeneity of risk for invasive anal cancer among PWH suggests the value of a shared decision-making framework regarding screening. METHODS Using a longitudinal HIV cohort with a comprehensive anal cancer screening program, we estimated the adjusted probabilities of having aHSIL on the first anal cytology. We used logistic regression models with inverse probability weighting to account for differential screening in the cohort and to construct a predicted probability nomogram for aHSIL. Sensitivity analysis was performed to estimate aHSIL prevalence corrected for misclassification bias. RESULTS Of 8139 PWH under care between 2007 and 2020, 4105 (49.8%) underwent at least 1 anal cytology test. First-time cytology aHSIL was present in 502 (12.2%) PWH. The adjusted probability of having aHSIL varied from 5% to 18% depending on patient characteristics. Prespecified factors in the aHSIL prediction model included nadir CD4 cell count, ethnicity, race, age, sex, gender identity, and HIV risk factors. The ability of the model to discriminate cytological aHSIL was modest, with an area under the curve of 0.63 (95% confidence interval, .60-.65). CONCLUSIONS PWH are at increased risk for aHSIL and invasive anal cancer. Risk, however, varies by patient characteristics. Individual risk factor profiles predictive of aHSIL can be modeled and operationalized as nomograms to facilitate shared decision-making conversations concerning anal cancer screening.
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Affiliation(s)
- Edward R Cachay
- Department of Medicine, Owen Clinic, University of California–San Diego, San Diego, California, USA
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California–San Diego, San Diego, California, USA
| | - Tari Gilbert
- Department of Medicine, Owen Clinic, University of California–San Diego, San Diego, California, USA
| | - Robert Deiss
- Department of Medicine, Owen Clinic, University of California–San Diego, San Diego, California, USA
- Department of Medicine, Division of Infectious Diseases and Global Public Health, University of California–San Diego, San Diego, California, USA
| | - Wm Christopher Mathews
- Department of Medicine, Owen Clinic, University of California–San Diego, San Diego, California, USA
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Assaf RD, Cunningham NJ, Adamson PC, Jann JT, Bolan RK. High proportions of rectal and pharyngeal chlamydia and gonorrhoea cases among cisgender men are missed using current CDC screening recommendations. Sex Transm Infect 2022; 98:586-591. [PMID: 35217590 PMCID: PMC9402804 DOI: 10.1136/sextrans-2021-055361] [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: 11/15/2021] [Accepted: 02/06/2022] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVES Pharyngeal and rectal Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections are often undiagnosed due to their asymptomatic nature. This study aims to determine (1) the prevalence of CT/NG infections by anatomical site among cisgender men; (2) the proportion of missed CT/NG rectal/pharyngeal infections if urogenital testing alone was performed or screening depended on self-reported behaviour alone; and (3) the predictive probability of self-reported behaviours for rectal CT/NG. METHODS This cross-sectional study used electronic health records collected at a sexual health clinic in Los Angeles from 18 November 2018 until 28 February 2020. The included patients were ≥18 years of age cisgender men who received CT/NG testing at least once during the study period. We calculated the proportion of missed pharyngeal/rectal CT/NG infections if only urogenital testing had been done and if testing was based only on self-reported anal sex. Separately, we ran logistic regressions for predictive probability of self-reported anal sex on CT/NG rectal infections. RESULTS Overall, there were 13 476 unique patients with 26 579 visits. The prevalence of any extragenital CT/NG infection was 37.28%. Over 80% rectal/pharyngeal CT cases and over 65% rectal/pharyngeal NG cases would be missed if urogenital testing alone was performed. Likewise, over 35% rectal CT/NG cases would be missed had testing relied on self-reported sexual behaviours alone. CONCLUSIONS The proportion of missed rectal and pharyngeal CT/NG infections is high. Our data from a sexual health clinic lend support to three-site opt-out testing for cisgender men attending a sexual health/Lesbian, Gay, Bisexual, Transgender, Queer/Questioning (LGBTQ+) specialty clinic regardless of their sexual orientation or reported sexual behaviours.
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Affiliation(s)
- Ryan D Assaf
- Health Services, Los Angeles LGBT Center, Los Angeles, California, USA
- Epidemiology, University of California Los Angeles Jonathan and Karin Fielding School of Public Health, Los Angeles, California, USA
| | | | - Paul C Adamson
- Division of Infectious Diseases, David Geffen School of Medicine, Los Angeles, California, USA
| | | | - Robert K Bolan
- Health Services, Los Angeles LGBT Center, Los Angeles, California, USA
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Li J, Armon C, Palella FJ, Novak RM, Ward D, Purinton S, Durham M, Buchacz K. Chlamydia and Gonorrhea Incidence and Testing Among Patients in the Human Immunodeficiency Virus Outpatient Study (HOPS), 2007-2017. Clin Infect Dis 2021; 71:1824-1835. [PMID: 31689341 DOI: 10.1093/cid/ciz1085] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 10/30/2019] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Although chlamydia (CT) and gonorrhea (GC) infections are increasing in the United States, there are limited data on their incidence, testing rates, and associated risk factors among persons living with HIV (PLWH), including by anatomic site among men who have sex with men (MSM). METHODS We analyzed 2007-2017 medical records data from Human Immunodeficiency Virus (HIV) Outpatient Study (HOPS) participants in care at 9 HIV clinics. We calculated CT (and GC) incidence and testing rates and assessed associations with sociodemographic and clinical factors using log-linear regression. RESULTS Among 4727 PLWH, 397 had 881 CT infections and 331 had 861 GC infections, with an incidence of 2.95 and 2.88 per 100 person-years, respectively. From 2007 to 2017, incidence and testing rates increased by approximately 3.0- and 1.9-fold for CT and GC, respectively. Multivariable factors associated with incident CT (GC) included younger age, MSM, and prior diagnoses of sexually transmitted diseases (STDs). Among 1159 MSM, 583 (50.3%) had 844 CT and 843 GC tests during 2016-2017, and 26.6% of tests were 3-site (urethra, rectum, and pharynx), yielding the highest rates of CT (GC) detection. Multivariable factors associated with CT (GC) testing included younger age, non-Hispanic/Latino black race, and having prior STDs. CONCLUSIONS Recent CT and GC incidence and testing increased among PLWH; however, only half of MSM were tested for CT or GC during 2016-2017 and less than a third of tests were 3-site. To promote sexual health and STD prevention among PLWH who are MSM, research regarding the added value of CT and GC testing across 3 anatomic sites is needed.
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Affiliation(s)
- Jun Li
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Carl Armon
- Cerner Corporation, Kansas City, Missouri, USA
| | - Frank J Palella
- Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Richard M Novak
- University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Douglas Ward
- Dupont Circle Physicians Group, Washington, District of Columbia, USA
| | | | - Marcus Durham
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Kate Buchacz
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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Extragenital Infections Caused by Chlamydia trachomatis and Neisseria gonorrhoeae: A Review of the Literature. Infect Dis Obstet Gynecol 2016; 2016:5758387. [PMID: 27366021 PMCID: PMC4913006 DOI: 10.1155/2016/5758387] [Citation(s) in RCA: 207] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 04/12/2016] [Accepted: 04/20/2016] [Indexed: 12/30/2022] Open
Abstract
In the United States, sexually transmitted diseases due to Chlamydia trachomatis and Neisseria gonorrhoeae continue to be a major public health burden. Screening of extragenital sites including the oropharynx and rectum is an emerging practice based on recent studies highlighting the prevalence of infection at these sites. We reviewed studies reporting the prevalence of extragenital infections in women, men who have sex with men (MSM), and men who have sex only with women (MSW), including distribution by anatomical site. Among women, prevalence was found to be 0.6–35.8% for rectal gonorrhea (median reported prevalence 1.9%), 0–29.6% for pharyngeal gonorrhea (median 2.1%), 2.0–77.3% for rectal chlamydia (median 8.7%), and 0.2–3.2% for pharyngeal chlamydia (median 1.7%). Among MSM, prevalence was found to be 0.2–24.0% for rectal gonorrhea (median 5.9%), 0.5–16.5% for pharyngeal gonorrhea (median 4.6%), 2.1–23.0% for rectal chlamydia (median 8.9%), and 0–3.6% for pharyngeal chlamydia (median 1.7%). Among MSW, the prevalence was found to be 0–5.7% for rectal gonorrhea (median 3.4%), 0.4–15.5% for pharyngeal gonorrhea (median 2.2%), 0–11.8% for rectal chlamydia (median 7.7%), and 0–22.0% for pharyngeal chlamydia (median 1.6%). Extragenital infections are often asymptomatic and found in the absence of reported risk behaviors, such as receptive anal and oral intercourse. We discuss current clinical recommendations and future directions for research.
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van Liere GAFS, Dirks JAMC, Hoebe CJPA, Wolffs PF, Dukers-Muijrers NHTM. Anorectal Chlamydia trachomatis Load Is Similar in Men Who Have Sex with Men and Women Reporting Anal Sex. PLoS One 2015; 10:e0134991. [PMID: 26262680 PMCID: PMC4532443 DOI: 10.1371/journal.pone.0134991] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 07/15/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Anorectal Chlamydia trachomatis (chlamydia) is frequently diagnosed in men who have sex with men (MSM) and in women, but it is unknown whether these infections are comparable in clinical impact and transmission potential. Quantifying bacterial load and identifying determinants associated with high bacterial load could provide more insight. METHODS We selected a convenience sample of MSM who reported anal sex (n = 90) and women with concurrent urogenital/anorectal chlamydia who reported anal sex (n = 51) or did not report anal sex (n = 61) from the South Limburg Public Health Service's STI unit. Bacterial load (Chlamydia/ml) was quantified for all samples and log transformed for analyses. Samples with an unquantifiable human leukocyte antigen (n = 9) were excluded from analyses, as they were deemed inadequately sampled. RESULTS The mean log anorectal chlamydia load (3.50) was similar for MSM and women who reported having anal sex (3.80, P = 0.21). The anorectal chlamydia load was significantly higher in these groups than in women who did not report having anal sex (2.76, P = 0.001). Detectable load values ranged from 1.81-6.32 chlamydia/ml for MSM, 1.74-7.33 chlamydia/ml for women who reported having anal sex and 1.84-6.31 chlamydia/ml for women who did not report having anal sex. Symptoms and several other determinants were not associated with anorectal chlamydia load. CONCLUSIONS Women who did not report anal sex had lower anorectal loads, but they were within a similar range to the other two groups. Anorectal chlamydia load was comparable between MSM and women who reported anal sex, suggesting similar transmission potential.
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Affiliation(s)
- Geneviève A. F. S. van Liere
- Department of Sexual Health, Infectious Diseases and Environmental Health, South Limburg Public Health Service, Geleen, the Netherlands
- Department of Medical Microbiology, School of Public Health and Primary Care (CAPHRI), Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands
- * E-mail:
| | - Jeanne A. M. C. Dirks
- Department of Medical Microbiology, School of Public Health and Primary Care (CAPHRI), Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands
| | - Christian J. P. A. Hoebe
- Department of Sexual Health, Infectious Diseases and Environmental Health, South Limburg Public Health Service, Geleen, the Netherlands
- Department of Medical Microbiology, School of Public Health and Primary Care (CAPHRI), Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands
| | - Petra F. Wolffs
- Department of Medical Microbiology, School of Public Health and Primary Care (CAPHRI), Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands
| | - Nicole H. T. M. Dukers-Muijrers
- Department of Sexual Health, Infectious Diseases and Environmental Health, South Limburg Public Health Service, Geleen, the Netherlands
- Department of Medical Microbiology, School of Public Health and Primary Care (CAPHRI), Maastricht University Medical Center + (MUMC+), Maastricht, the Netherlands
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Prevalence and characteristics of rectal chlamydia and gonorrhea cases among men who have sex with men after the introduction of nucleic acid amplification test screening at 2 Canadian sexually transmitted infection clinics. Sex Transm Dis 2015; 41:589-91. [PMID: 25211252 DOI: 10.1097/olq.0000000000000176] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We sought to determine the prevalence of rectal chlamydia and gonorrhea after the introduction of nucleic acid amplification tests for screening in men reporting receptive anal intercourse. The rectal chlamydia prevalence was 14.1% (95% confidence interval, 11.9-16.3), and the gonorrhea prevalence was 5.9% (95% confidence interval, 4.4-7.3). Most cases were positive only from the rectum.
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Gratrix J, Singh AE, Bergman J, Egan C, Plitt SS, McGinnis J, Bell CA, Drews SJ, Read R. Evidence for Increased Chlamydia Case Finding After the Introduction of Rectal Screening Among Women Attending 2 Canadian Sexually Transmitted Infection Clinics. Clin Infect Dis 2014; 60:398-404. [DOI: 10.1093/cid/ciu831] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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High prevalence of sexually transmitted infections in HIV-infected men during routine outpatient visits in the Netherlands. Sex Transm Dis 2014; 39:8-15. [PMID: 22183837 DOI: 10.1097/olq.0b013e3182354e81] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND In the Netherlands, no guidelines exist for routine sexually transmitted infection (STI) screening of human immunodeficiency virus (HIV)-infected men having sex with men (MSM). We assessed prevalence and factors associated with asymptomatic STI. METHODS MSM visiting HIV outpatient clinics of academic hospitals were tested for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), syphilis, and hepatitis B and C infection. Prevalence and risk factors were studied using logistic regression. RESULTS In total, 659 MSM were included between 2007 and 2008. STI were found in 16.0% of patients, mostly anal CT and syphilis. One new hepatitis B and 3 new hepatitis C infections were identified. In multivariate analyses, any STI (syphilis, CT, or NG) was associated with patient's age below 40 years (odds ratio [OR]: 2.5, 95% confidence interval [CI]: 1.3-5.0), having had sex with 2 or more sexual partners (OR 2.1, 95% CI: 1.2-3.5), the use of the same sexual toys with a sexual partner (OR 2.2, 95% CI: 1.0-4.9), and enema use before sex (OR: 2.3, 95% 1.2-4.2). Syphilis was independently associated with fisting with gloves versus no fisting (OR: 4.9, 95% CI: 1.7-13.7) and with rimming (OR: 5.0, 95% CI: 1.7-15.0). CT or NG were associated with age below 45 years (age 40-44 years: OR: 2.4, 95% CI: 1.1-5.3; age <40 years: OR: 2.4, 95% CI: 1.1-5.4), enema use before sex (OR: 2.4, 95% CI: 1.3-4.4) and drug use during sex (OR: 2.4, 95% CI: 1.4-4.0). CONCLUSIONS High-risk sexual behavior was very common, and 16% of HIV-infected MSM in HIV care had an asymptomatic STI, mostly anal CT and syphilis. Development of STI screening guidelines is recommended.
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Standard Symptom- and Sexual History–Based Testing Misses Anorectal Chlamydia trachomatis and Neisseria gonorrhoeae Infections in Swingers and Men Who Have Sex With Men. Sex Transm Dis 2013; 40:285-9. [DOI: 10.1097/olq.0b013e31828098f8] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Berry SA, Ghanem KG, Page KR, Gange SJ, Thio CL, Moore RD, Gebo KA. Increased gonorrhoea and chlamydia testing did not increase case detection in an HIV clinical cohort 1999-2007. Sex Transm Infect 2011; 87:469-75. [PMID: 21745834 DOI: 10.1136/sextrans-2011-050051] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVES Since 2003, US organisations have recommended universal screening, rather than targeted screening, of HIV-infected persons for gonorrhoea and chlamydia. The objective of this study was to determine whether wider testing resulting from these guidelines would produce an increase in gonorrhoea/chlamydia diagnoses. METHODS 3283 patients receiving HIV care in 1999-2007 in the Johns Hopkins Hospital HIV clinic were studied. The two primary outcomes were the occurrence of any gonorrhoea/chlamydia testing in each year of care and the occurrence of any positive result(s) in years of testing. The proportion of all patients in care who were diagnosed with gonorrhoea/chlamydia was defined as the number of patients with positive results divided by the number of patients in care. Trends were analysed with repeated measures logistic regression. RESULTS The proportion of patients tested for gonorrhoea/chlamydia increased steadily from 0.12 in 1999 to 0.33 in 2007 (OR per year for being tested 1.17, 95% CI 1.15 to 1.19). The proportion positive among those tested decreased significantly after 2003 (OR per year 0.67, 95% CI 0.55 to 0.81). The proportion of all patients in care diagnosed with gonorrhoea/chlamydia therefore remained generally stable in 1999-2007 (OR per year 0.97, 95% CI 0.91 to 1.04). CONCLUSIONS Universal annual screening, as implemented, did not increase the proportion of all patients in care who were diagnosed with gonorrhoea/chlamydia. Similarly low implementation rates have been reported in cross-sectional studies. If future efforts to enhance implementation do not yield increases in diagnoses, then guidelines focusing on targeted screening of high-risk groups rather than universal screening may be warranted.
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Affiliation(s)
- Stephen A Berry
- Division of Infectious Diseases, Johns Hopkins University School of Medicine, Baltimore, MD 21287-2100, USA.
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