RESUMEN
Research using nucleic acid amplification tests (NAATs) have repeatedly found rectal and oropharyngeal infections with Chlamydia trachomatis and Neisseria gonorrhoeae to be common and potentially more difficult to treat than genital infections. Unfortunately, public health and patient care efforts have been hampered by the lack of FDA-cleared NAATs with claims for anorectal or oropharyngeal samples. At the time of the initiation of this study, no commercially available assays had these claims. We formed a novel partnership among academic institutions and diagnostic manufacturers to address this public health need. From May 2018 through August 2019, we recruited 1108 women, 1256 men, and 26 transgender persons each of whom provided 3 anal and 3 oropharyngeal swab specimens. The 3 anal swabs were pooled into a single transport tube as were the 3 oropharyngeal swabs. The performance of each of three study assays was estimated by comparison to the composite result and relative to one another. Percent positivity for chlamydia was 5.9 and 1.2% from anal and oropharyngeal specimens, respectively, compared to 4.2 and 4.1% for gonorrhea. Sensitivity for chlamydia detection ranged from 81.0 to 95.1% and 82.8 to 100% for anal and oropharyngeal specimens, respectively. Gonorrhea sensitivity ranged from 85.9 to 99.0% and 74.0 to 100% for anal and oropharyngeal samples, respectively. Specificity estimates were ≥ 98.9% for all assays, organisms, and sample types. Although there was heterogeneity between sensitivity estimates, these assays offer better ability to detect extragenital infections than culture and potential solutions for providing appropriate sexual health care for populations in which these infections are of concern.
Asunto(s)
Infecciones por Chlamydia , Gonorrea , Infecciones por Chlamydia/diagnóstico , Chlamydia trachomatis/genética , Femenino , Gonorrea/diagnóstico , Humanos , Masculino , Neisseria gonorrhoeae/genética , Técnicas de Amplificación de Ácido Nucleico , Sensibilidad y EspecificidadRESUMEN
Nucleic acid amplification tests are increasingly used to detect ocular chlamydia infection in trachoma research and programs. To evaluate the reliability of Chlamydia trachomatis detection by the Abbott RealTime CT/NG assay (Abbott Molecular, Inc., Des Plaines, IL) on the m2000 platform, three conjunctival samples were collected from each of 200 children aged 0-9 years in Ethiopia: two from the right eye and one from the left eye. Four aliquots were processed for each child: two from the first right eye sample, one from the second right eye sample, and one from the left eye sample. Sixty-nine swabs were processed in a U.S. laboratory and 131 in an Ethiopian laboratory. Intra-class correlation coefficients (ICCs) were high when comparing two aliquots from the same swab (ICC ranged from 0.96 to 0.99), two separate swabs from the right eye (0.89-0.91), and one right and one left eye swab (0.87-0.89), indicating reliable chlamydial load assessment across different samples and laboratory settings.
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Chlamydia trachomatis , Conjuntivitis de Inclusión/diagnóstico , Técnicas de Amplificación de Ácido Nucleico/métodos , Niño , Preescolar , Conjuntivitis de Inclusión/epidemiología , Conjuntivitis de Inclusión/microbiología , Estudios Transversales , Etiopía/epidemiología , Ojo/microbiología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: After approximately 5 years of SAFE (surgery, antibiotics, facial cleanliness, environmental improvement) interventions for trachoma, hyperendemic (trachomatous inflammation-follicular (TF) ≥30%) districts remained in Amhara, Ethiopia. This study's aim was to characterize the epidemiology of Chlamydia trachomatis (Ct) infection and load among pre-school aged children living under the SAFE strategy. METHODS: Conjunctival swabs from a population-based sample of children aged 1-5 years collected between 2011 and 2015 were assayed to provide Ct infection data from 4 endemic zones (comprised of 58 districts). Ct load was determined using a calibration curve. Children were graded for TF and trachomatous inflammation-intense (TI). RESULTS: 7,441 children were swabbed in 4 zones. TF and TI prevalence were 39.9% (95% confidence Interval [CI]: 37.5%, 42.4%), and 9.2% (95% CI: 8.1%, 10.3%) respectively. Ct infection prevalence was 6.0% (95% CI: 5.0%, 7.2%). Infection was highest among children aged 2 to 4 years (6.6%-7.0%). Approximately 10% of infection occurred among children aged 1 year. Ct load decreased with age (P = 0.002), with the highest loads observed in children aged 1 year (P = 0.01) vs. aged 5 years. Participants with TF (P = 0.20) and TI (P<0.01) had loads greater than individuals without active trachoma. CONCLUSIONS: In this hyperendemic setting, it appears that the youngest children may contribute in meaningful ways towards persistent active trachoma.
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Chlamydia trachomatis/fisiología , Tracoma/epidemiología , Tracoma/prevención & control , Antibacterianos/administración & dosificación , Preescolar , Chlamydia trachomatis/efectos de los fármacos , Conjuntiva/microbiología , Enfermedades Endémicas/prevención & control , Etiopía/epidemiología , Femenino , Humanos , Lactante , Masculino , Tracoma/tratamiento farmacológico , Tracoma/microbiologíaRESUMEN
Background: World Health Organization (WHO) recommendations for starting and stopping mass antibiotic distributions are based on a clinical sign of trachoma, which is indirectly related to actual infection with the causative agent, Chlamydia trachomatis. Methods: This study aimed to understand the effect of SAFE (surgery, antibiotics, facial cleanliness, and environmental improvement) interventions on ocular chlamydia in Amhara, Ethiopia, by describing the infection prevalence in a population-based sample of children aged 1-5 years. Trachoma surveys were conducted in all districts of Amhara, from 2011 to 2015 following approximately 5 years of SAFE. Ocular swabs were collected from randomly selected children to estimate the zonal prevalence of chlamydial infection. The Abbott RealTime polymerase chain reaction assay was used to detect C. trachomatis DNA. Results: A total of 15632 samples were collected across 10 zones of Amhara. The prevalence of chlamydial infection in children aged 1-5 years was 5.7% (95% confidence interval, 4.2%-7.3%; zonal range, 1.0%-18.5%). Chlamydial infection and trachomatous inflammation-intense (TI) among children aged 1-9 years were highly correlated at the zonal level (Spearman correlation [r] = 0.93; P < .001), while chlamydial infection and trachomatous inflammation-follicular were moderately correlated (r = 0.57; P = .084). Conclusions: After 5 years of SAFE, there is appreciable chlamydial infection in children aged 1-5 years, indicating that transmission has not been interrupted and that interventions should continue. The sign TI was highly correlated with chlamydial infection and can be used as a proxy indicator of infection.
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Chlamydia trachomatis/aislamiento & purificación , Ojo/microbiología , Tracoma/epidemiología , Tracoma/prevención & control , Preescolar , Etiopía/epidemiología , Femenino , Humanos , Lactante , Masculino , PrevalenciaRESUMEN
Chlamydia trachomatis is the world's most prevalent bacterial sexually transmitted infection and leading infectious cause of blindness, yet it is one of the least understood human pathogens, in part due to the difficulties of in vitro culturing and the lack of available tools for genetic manipulation. Genome sequencing has reinvigorated this field, shedding light on the contemporary history of this pathogen. Here, we analyze 563 full genomes, 455 of which are novel, to show that the history of the species comprises two phases, and conclude that the currently circulating lineages are the result of evolution in different genomic ecotypes. Temporal analysis indicates these lineages have recently expanded in the space of thousands of years, rather than the millions of years as previously thought, a finding that dramatically changes our understanding of this pathogen's history. Finally, at a time when almost every pathogen is becoming increasingly resistant to antimicrobials, we show that there is no evidence of circulating genomic resistance in C. trachomatis.
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Chlamydia trachomatis/genética , Farmacorresistencia Bacteriana/genética , Ecotipo , Evolución Molecular , Genoma Bacteriano , Chlamydia trachomatis/aislamiento & purificación , Femenino , Humanos , MasculinoRESUMEN
The Aptima Combo 2 (AC2) and Aptima CT (ACT) (Hologic Inc., San Diego, CA) are nucleic acid amplification tests (NAATs) that detect Chlamydia trachomatis AC2 also detects Neisseria gonorrhoeae Storage and temperature conditions may impact the utility of NAATs in some settings and screening programs. We evaluated specimen stability for use beyond the Aptima package insert specifications for temperature and duration of storage (between 2°C and 30°C and 60 days, respectively) in two studies: (i) dry C. trachomatis-seeded swabs were used with ACT after storage at 4°C, 23°C, or 36°C for up to 84 days and (ii) swabs seeded with C. trachomatis and N. gonorrhoeae and then placed in transport medium were tested with AC2, after being mailed via the U.S. Postal Service to three different sites. Prolonged storage of samples had no effect, and samples stored at 4°C, 23°C, and 36°C for up to 84 days yielded comparable ACT positivities, although there was a drop in signal intensity for virtually all specimens under all storage/shipping conditions after day 21. In the mailing study, 80%, 52% and 29% of seeded swabs were exposed to temperatures of >30°C during three rounds in transit, and 2% reached temperatures of >40°C. No evidence of signal degradation in the AC2 assay for detection of C. trachomatis or N. gonorrhoeae was observed, although some mailed swabs took more than 5 weeks to reach the laboratory site. These two studies support the potential use of swabs at temperatures above 36°C and storage beyond 60 days and provide confidence regarding this commercially available NAAT for testing of specimens after mailing.
Asunto(s)
Técnicas Bacteriológicas/métodos , Infecciones por Chlamydia/diagnóstico , Chlamydia trachomatis/aislamiento & purificación , Gonorrea/diagnóstico , Neisseria gonorrhoeae/aislamiento & purificación , Manejo de Especímenes/métodos , Humanos , Temperatura , Factores de Tiempo , Estados UnidosRESUMEN
We evaluated Abbott's RealTime assay for the detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) in the urethra, oropharynx, and rectum of 260 men who have sex with men. Compared with Hologic's AC2, RealTime had good agreement for detecting CT and GC. Overall, there were 25 CT and 44 GC AC2 positives, and 26 CT and 38 GC RealTime positives. For total negatives, there were 742 CT and 725 GC for AC2, 744 CT and 724 GC for RealTime.
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Técnicas de Tipificación Bacteriana/instrumentación , Infecciones por Chlamydia/diagnóstico , Chlamydia trachomatis/aislamiento & purificación , Gonorrea/diagnóstico , Homosexualidad Masculina , Neisseria gonorrhoeae/aislamiento & purificación , Orofaringe/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa/instrumentación , Recto/microbiología , Uretra/microbiología , Adulto , Infecciones por Chlamydia/prevención & control , Infecciones por Chlamydia/transmisión , Chlamydia trachomatis/genética , Gonorrea/prevención & control , Gonorrea/transmisión , Humanos , Masculino , Neisseria gonorrhoeae/genética , Juego de Reactivos para Diagnóstico , San Francisco/epidemiología , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Trachoma, caused by repeated infections with ocular Chlamydia trachomatis, is targeted for elimination using multiple annual rounds of mass drug administration (MDA) in endemic communities. Infection rates do not decline as expected in some communities, leading to concerns about azithromycin resistance. METHODS: After 3 yearly MDAs in 32 communities in Tanzania, 107 children were identified 1 year later with infection. All were provided MDA again, and 90 were seen again at 2 months, of whom 30 had infection. Chlamydia trachomatis isolates were obtained before and after MDA in 15 paired samples and were tested for antimicrobial susceptibility. The infectious load of C. trachomatis before MDA was determined in 30 children who had infection at both times and 60 whose infection cleared. RESULTS: The median load was 8.6 genome copies per polymerase chain reaction in the consistently infected, and 8.4 in those whose infection cleared (P = .86). For the consistently infected, the average minimum inhibitory concentration was 0.26 µg/mL for azithromycin before and 0.20 µg/mL after MDA. All isolates had minimum inhibitory concentration ≤0.50 µg/mL. CONCLUSIONS: There is no evidence that continued infection after MDA was due either to resistance to azithromycin or to a heavier load of organism before treatment. Other potential causes of persistent infection need to be evaluated.
Asunto(s)
Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Chlamydia trachomatis/efectos de los fármacos , Farmacorresistencia Bacteriana , Tracoma/tratamiento farmacológico , Tracoma/microbiología , Antibacterianos/farmacología , Azitromicina/farmacología , Niño , Preescolar , Chlamydia trachomatis/aislamiento & purificación , Quimioterapia/métodos , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , Prevención Secundaria , Tanzanía/epidemiología , Tracoma/epidemiología , Tracoma/prevención & controlRESUMEN
A specific real-time polymerase chain reaction followed by melt curve analysis was developed for the detection of the Swedish variant (nvCT) strain of Chlamydia trachomatis (CT). Surveillance was performed on 476 CT-positive clinical specimens obtained from 15 laboratories around the United States using nucleic acid amplification test assays, which would not miss the nvCT. All were negative for nvCT; thus, there is no evidence of the nvCT in the United States.
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Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis/aislamiento & purificación , Enfermedades Transmisibles Emergentes/epidemiología , Infecciones por Chlamydia/clasificación , Infecciones por Chlamydia/genética , Chlamydia trachomatis/clasificación , Enfermedades Transmisibles Emergentes/genética , Femenino , Genotipo , Humanos , Masculino , Noruega/epidemiología , Técnicas de Amplificación de Ácido Nucleico , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Conducta Sexual , Suecia/epidemiología , Estados Unidos/epidemiologíaRESUMEN
OBJECTIVE: The authors evaluated the use of conditional cash transfers as an HIV and sexually transmitted infection prevention strategy to incentivise safe sex. DESIGN: An unblinded, individually randomised and controlled trial. SETTING: 10 villages within the Kilombero/Ulanga districts of the Ifakara Health and Demographic Surveillance System in rural south-west Tanzania. PARTICIPANTS: The authors enrolled 2399 participants, aged 18-30 years, including adult spouses. INTERVENTIONS: Participants were randomly assigned to either a control arm (n=1124) or one of two intervention arms: low-value conditional cash transfer (eligible for $10 per testing round, n=660) and high-value conditional cash transfer (eligible for $20 per testing round, n=615). The authors tested participants every 4 months over a 12-month period for the presence of common sexually transmitted infections. In the intervention arms, conditional cash transfer payments were tied to negative sexually transmitted infection test results. Anyone testing positive for a sexually transmitted infection was offered free treatment, and all received counselling. MAIN OUTCOME MEASURES: The primary study end point was combined prevalence of the four sexually transmitted infections, which were tested and reported to subjects every 4 months: Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis and Mycoplasma genitalium. The authors also tested for HIV, herpes simplex virus 2 and syphilis at baseline and month 12. RESULTS: At the end of the 12-month period, for the combined prevalence of any of the four sexually transmitted infections, which were tested and reported every 4 months (C trachomatis, N gonorrhoeae, T vaginalis and M genitalium), unadjusted RR for the high-value conditional cash transfer arm compared to controls was 0.80 (95% CI 0.54 to 1.06) and the adjusted RR was 0.73 (95% CI 0.47 to 0.99). Unadjusted RR for the high-value conditional cash transfer arm compared to the low-value conditional cash transfer arm was 0.76 (95% CI 0.49 to 1.03) and the adjusted RR was 0.69 (95% CI 0.45 to 0.92). No harm was reported. CONCLUSIONS: Conditional cash transfers used to incentivise safer sexual practices are a potentially promising new tool in HIV and sexually transmitted infections prevention. Additional larger study would be useful to clarify the effect size, to calibrate the size of the incentive and to determine whether the intervention can be delivered cost effectively. TRIAL REGISTRATION NUMBER: NCT00922038 ClinicalTrials.gov.
RESUMEN
PURPOSE: Although trachoma control programs frequently use the World Health Organization (WHO) simplified grading system for trachoma to monitor the clinical response after repeated mass azithromycin treatments, the programmatic relevance of this evaluation after multiple rounds of antibiotic treatments is unclear. METHODS: Three rounds of annual mass azithromycin were distributed to 12 villages in Ethiopia. Twelve months after the third treatment, children were assessed for follicular trachomatous inflammation (TF) and intense trachomatous inflammation (TI) using the WHO simplified grading system and for ocular chlamydial infection using DNA-based and RNA-based tests. Test characteristics for predicting chlamydial infection were computed assuming a chlamydial RNA-based gold standard. As a secondary analysis, test characteristics were also assessed using a latent class analysis. RESULTS: The prevalence of RNA evidence of ocular chlamydia was 7.1% (95% confidence interval [CI], 2.7-17.4). A DNA-based test and TF had sensitivities of 61.0% (95% CI, 47.1-73.3) and 65.9% (95% CI, 41.6-83.9), specificities of 100% (95% CI, 99.3-100) and 67.5% (95% CI, 61.0-73.5), and positive predictive values of 100% (95% CI, 86.3-100) and 13.4% (95% CI, 5.5-29.3) compared with an RNA-based gold standard. The latent class analysis confirmed that the RNA-based test was a reasonable choice for a gold standard, with a sensitivity of 100% (95% CI, 67.1-100) and specificity of 99.6% (95% CI, 98.1-100). CONCLUSIONS: Basing treatment decisions after mass azithromycin distributions on the WHO simplified grading system will maximize the treatment of infected persons compared with a DNA-based test but will also result in more uninfected persons being treated. The RNA-based test was considerably more sensitive, and almost equivalently specific, compared with a DNA-based test. (ClinicalTrials.gov number, NCT00322972.).
Asunto(s)
Antibacterianos/administración & dosificación , Profilaxis Antibiótica , Azitromicina/administración & dosificación , Chlamydia trachomatis/aislamiento & purificación , Técnicas de Diagnóstico Oftalmológico , Tracoma/diagnóstico , Tracoma/microbiología , Niño , Preescolar , Chlamydia trachomatis/genética , Análisis por Conglomerados , Control de Enfermedades Transmisibles , ADN Bacteriano/análisis , Etiopía/epidemiología , Reacciones Falso Positivas , Femenino , Humanos , Lactante , Recién Nacido , Funciones de Verosimilitud , Masculino , Reacción en Cadena de la Polimerasa , Valor Predictivo de las Pruebas , ARN Bacteriano/análisis , ARN Ribosómico 16S/genética , Población Rural , Sensibilidad y Especificidad , Tracoma/prevención & controlRESUMEN
Twelve trachoma-hyperendemic communities were treated with 3 annual mass azithromycin distributions. Children aged 0-9 years were monitored 1 year following the third treatment. An RNA-based test detected ocular chlamydial infection in more children than did a DNA-based test (6.9% vs 4.2%), and in a larger number of communities (8 vs 7).
Asunto(s)
Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Chlamydia trachomatis/aislamiento & purificación , ARN Bacteriano/análisis , ARN Ribosómico/análisis , Tracoma/prevención & control , Profilaxis Antibiótica/métodos , Niño , Preescolar , Chlamydia trachomatis/genética , Etiopía/epidemiología , Femenino , Humanos , Lactante , Masculino , Prevalencia , Servicios Preventivos de Salud , ARN Bacteriano/genética , ARN Ribosómico/genética , Estadísticas no Paramétricas , Tracoma/tratamiento farmacológico , Tracoma/epidemiología , Tracoma/microbiologíaRESUMEN
BACKGROUND: An important component of the World Health Organization's comprehensive trachoma elimination strategy is the provision of repeated annual mass azithromycin distributions, which are directed at reducing the burden of ocular chlamydia. Knowledge of characteristics associated with infection after mass antibiotic treatments could allow trachoma programs to focus resources to those most likely to be infected with ocular chlamydia. METHODOLOGY/PRINCIPAL FINDINGS: We monitored 12 communities in rural Ethiopia that had received 3 annual mass azithromycin treatments as part of a cluster-randomized trial for trachoma. One year after the third treatment, a random sample of children from each village received conjunctival examination for follicular trachomatous inflammation (TF) and intense trachomatous inflammation (TI), conjunctival swabbing for chlamydial RNA and DNA, and a household survey. The primary outcome for this study was RNA evidence of ocular chlamydia, which we detected in 41 of 573 swabbed children (7.2%, 95%CI 2.7-17.8). In multivariate mixed effects logistic regression models, ocular chlamydial RNA was significantly associated with ocular discharge (OR 2.82, 95%CI 1.07-7.42), missing the most recent mass azithromycin treatment (OR 2.49, 95%CI 1.02-6.05), having a sibling with ocular chlamydia (OR 4.44, 95%CI 1.60-12.29), and above-median community population (OR 7.81, 95%CI 1.56-39.09). Ocular chlamydial infection was also independently associated with TF (OR 3.42, 95%CI 1.56-7.49) and TI (OR 5.39, 95%CI 2.43-11.98). CONCLUSIONS/SIGNIFICANCE: In areas with highly prevalent trachoma treated with multiple rounds of mass azithromycin, trachoma programs could consider continuing mass azithromycin treatments in households that have missed prior mass antibiotic treatments, in households with clinically active trachoma, and in larger communities.
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Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Tracoma/tratamiento farmacológico , Tracoma/epidemiología , Niño , Preescolar , Chlamydia trachomatis/genética , Chlamydia trachomatis/aislamiento & purificación , Estudios Transversales , ADN Bacteriano/análisis , Etiopía/epidemiología , Composición Familiar , Femenino , Humanos , Modelos Logísticos , Masculino , Oportunidad Relativa , ARN Bacteriano/análisis , Factores de Riesgo , Factores Socioeconómicos , ViajeRESUMEN
OBJECTIVE: To determine whether infectious trachoma can be completely eliminated from severely affected villages. DESIGN: Cross-sectional survey of 2 villages previously enrolled and monitored over 42 months as part of a larger, group-randomized clinical trial. PARTICIPANTS: A total of 758 individuals residing in 2 villages with high baseline trachoma prevalence, of a total population of 768 (98.7%). METHODS: All members of the 2 villages were offered 6 biannual mass treatments with oral azithromycin. At 42 months, each current village member was examined. The right upper tarsal conjunctiva was everted and swabbed. Samples were processed for evidence of Chlamydia trachomatis RNA. MAIN OUTCOME MEASURES: Clinical activity by World Health Organization simplified grading scale for trachoma and laboratory evidence of chlamydial RNA. RESULTS: Average antibiotic coverage over the study period was 90% and 94% in the 2 villages. Clinical trachoma activity in children aged 1 to 5 years decreased from 78% and 83% in the 2 villages before treatment to 17% and 24% at 42 months. Polymerase chain reaction (PCR) evidence of infection in the same age group decreased from 48% to 0% in both villages at 42 months. When all age groups were examined, there were zero cases with evidence of chlamydial RNA among 758 total villagers tested. CONCLUSIONS: Biannual mass distribution of azithromycin can locally eliminate ocular chlamydial infection from severely affected communities.
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Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Tracoma/tratamiento farmacológico , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Chlamydia trachomatis/genética , Chlamydia trachomatis/aislamiento & purificación , Conjuntiva/microbiología , Estudios Transversales , Etiopía/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Prevalencia , ARN Bacteriano/análisis , Población Rural , Tracoma/epidemiología , Tracoma/microbiología , Adulto JovenRESUMEN
We investigated antimicrobial drug resistance in ocular Chlamydia trachomatis 18 months after 4 biannual communitywide distributions of antimicrobial drugs in a region of Ethiopia where ocular strains of C. trachomatis are highly endemic. We found no significant differences in susceptibilities to azithromycin and doxycycline in 6 posttreatment and 4 pretreatment samples.
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Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Chlamydia trachomatis/efectos de los fármacos , Farmacorresistencia Microbiana/genética , Oftalmopatías/microbiología , Administración Tópica , Adulto , Niño , Preescolar , Chlamydia trachomatis/genética , Cicloheximida/farmacología , Etiopía/epidemiología , Oftalmopatías/tratamiento farmacológico , Oftalmopatías/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Lactante , Masculino , Embarazo , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , PrevalenciaRESUMEN
Self-collected glans and rectal swab specimens from men who have sex with men (MSM) may be appropriate, convenient specimens for testing. We evaluated the use of self-collected swabs for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae by a transcription-mediated amplification test (AC2; Aptima Combo 2; Gen-Probe Inc.) and a strand displacement amplification test (SDA; ProbeTec; Becton Dickinson Co.) in MSM seen at the city sexually transmitted disease clinic in San Francisco, CA. For the glans swab specimen, subjects enrolled early in the study rolled a Dacron swab across the meatus three times (method 1). A slightly more invasive procedure was performed later in the study: the subjects inserted the swab 1/4 in. into the urethra, rotated the swab, and then withdrew the swab (method 2). MSM self-collected a rectal swab specimen and also provided first-catch urine (FCU). Additional rectal swab samples were then obtained by the clinician. For the detection of C. trachomatis and N. gonorrhoeae, all swabs were evaluated by AC2 and SDA, FCU was tested by AC2, and the clinician-collected rectal swabs were cultured. A rectal true-positive (TP) result was defined as a culture-positive result for C. trachomatis or N. gonorrhoeae, two or more positive nucleic acid amplification test (NAAT) results, or a single NAAT-positive result confirmed by an alternate amplification method (the Aptima C. trachomatis or N. gonorrhoeae test). A glans TP result was defined as a positive result for FCU, positive results for both glans specimens (one tested by AC2 and one tested by SDA), or a positive result for a single glans specimen confirmed by an alternate amplification method. The prevalence rates of C. trachomatis and N. gonorrhoeae by testing of FCU were 6.8% (60/882 specimens) and 12.2% (108/882 specimens), respectively. Mixed results were obtained with the glans swab: N. gonorrhoeae detection by AC2 and SDA (method 1) had the best performance (sensitivities, >92%) with samples from a population with a higher prevalence of infection, but their performance for the detection of C. trachomatis was poor and varied by collection method (sensitivities, 56 to 68%). The prevalence rates of C. trachomatis and N. gonorrhoeae in the rectum were 7.3% (66/907 specimens) and 9.4% (83/882 specimens), respectively. The sensitivities of the tests with self-collected and clinician-collected rectal swab specimens were comparable (for C. trachomatis, 41% and 44%, respectively, by SDA and 82% and 71%, respectively, by AC2; for N. gonorrhoeae, 77% and 68%, respectively, by SDA and 84% and 78%, respectively, by AC2). AC2 and SDA were far superior to culture for the detection of C. trachomatis and N. gonorrhoeae in the rectum, with both tests detecting at least twice as many infections. While we found self-collected rectal swabs from MSM to be valid specimens for testing, the sensitivities of the tests with glans swab specimens were disappointing except for those from patients with symptomatic N. gonorrhoeae infections. Self-collected glans swab specimens may not be appropriate for the detection of C. trachomatis or for the detection of N. gonorrhoeae in low-risk or asymptomatic patients by AC2 and SDA, and we would not recommend their use on the basis of our results. Further studies are needed.
Asunto(s)
Chlamydia trachomatis/aislamiento & purificación , Neisseria gonorrhoeae/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico/métodos , Pene/microbiología , Recto/microbiología , Autoexamen , Infecciones por Chlamydia/diagnóstico , Infecciones por Chlamydia/microbiología , Chlamydia trachomatis/genética , Gonorrea/diagnóstico , Gonorrea/microbiología , Investigación sobre Servicios de Salud , Homosexualidad Masculina , Humanos , Masculino , Neisseria gonorrhoeae/genética , Prevalencia , San Francisco , Sensibilidad y EspecificidadRESUMEN
PURPOSE: Trachoma remains the leading infectious cause of blindness worldwide. The World Health Organization (WHO) recommends mass antibiotic distributions in its strategy to eliminate blinding trachoma. To determine the most effective antibiotic treatment strategy, it is essential to have a diagnostic test that can correctly measure the true status of ocular Chlamydia trachomatis infection in individuals, particularly after treatment. A newer ribosomal ribonucleic acid (rRNA)-based amplification test was compared with the current DNA-based polymerase chain reaction (PCR) for the detection of C. trachomatis. METHODS: An rRNA-based assay and PCR were performed on swab specimens taken from the right upper tarsal conjunctiva of 240 children aged 1 to 5 years living among 16 endemic villages in the Gurage Zone, Ethiopia. RESULTS: The rRNA-based test detected ocular C. trachomatis infection in 142 (59%) subjects compared with 67 (28%) detected by PCR (McNemar's test, P < 0.0001). The rRNA-based test gave positive results for all subjects who were positive by PCR and detected infection in 75 (31%) additional subjects. CONCLUSIONS: The rRNA-based test appears to have significantly greater sensitivity than PCR for the detection of ocular C. trachomatis infection in children in trachoma-endemic villages. The increased sensitivity of the rRNA-based test may be due to its ability to detect low levels of C. trachomatis infection in individuals, which can occur especially after antibiotic treatment. Data from past studies in which PCR was used to assess the prevalence of infectious trachoma after community-wide antibiotic treatments could have underestimated the true prevalence of infection.
Asunto(s)
Chlamydia trachomatis/aislamiento & purificación , Enfermedades Endémicas , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN Bacteriano/análisis , Tracoma/diagnóstico , Tracoma/epidemiología , Preescolar , Chlamydia trachomatis/genética , Conjuntiva/microbiología , Etiopía/epidemiología , Femenino , Humanos , Lactante , Masculino , Reacción en Cadena de la Polimerasa , ARN Ribosómico 16S/genética , Tracoma/microbiologíaRESUMEN
OBJECTIVE: To evaluate interrelationships between bacterial vaginosis (BV), vaginal yeast, vaginal practices (cleansing and drying/tightening), mucosal inflammation, and HIV acquisition. METHODS: A multicenter, prospective, observational cohort study was conducted, enrolling 4531 HIV-negative women aged 18 to 35 years attending family planning clinics in Zimbabwe and Uganda. Participants were tested for HIV and reproductive tract infections and were interviewed about vaginal practices every 3 months for 15 to 24 months. BV was measured by Gram stain Nugent scoring, vaginal yeast by wet mount, and mucosal inflammation by white blood cells on Gram stain. RESULTS: HIV incidence was 4.12 and 1.53 per 100 woman-years of follow-up in Zimbabwe and Uganda, respectively (a total of 213 incident infections). Women with BV or vaginal yeast were more likely to acquire HIV, especially if the condition was present at the same visit as the new HIV infection and the visit preceding it (hazard ratio [HR] = 2.50, 95% confidence interval [CI]: 1.68 to 3.72 and HR = 2.97, 95% CI: 1.67 to 5.28 for BV and yeast, respectively). These relationships did not seem to be mediated by mucosal inflammation. Vaginal drying/tightening was associated with HIV acquisition in univariate (HR = 1.49, 95% CI: 1.03 to 2.15) but not multivariate models. Vaginal cleansing was not associated with HIV acquisition. CONCLUSIONS: BV and yeast may contribute more to the HIV epidemic than previously thought.