Search

BACKGROUND Sexual transmission rates of Chlamydia trachomatis (Ct) cannot be measured directly; however, the study of concordance of Ct infection in sexual partnerships (dyads) can help to illuminate factors influencing Ct transmission. METHODS Heterosexual men and women with Ct infection and their sex partners were enrolled and partner-specific coital and behavioral data collected for the prior 30 days. Microbiological data included Ct culture, and nucleic acid amplification testing (NAAT), quantitative Ct polymerase chain reaction, and ompA genotyping. We measured Ct concordance in dyads and factors (correlates) associated with concordance. RESULTS One hundred twenty-one women and 125 men formed 128 dyads. Overall, 72.9% of male partners of NAAT-positive women and 68.6% of female partners of NAAT-positive men were Ct-infected. Concordance was more common in dyads with culture-positive members (78.6% of male partners, 77% of female partners). Partners of women and men who were NAAT-positive only had lower concordance (33.3%, 46.4%, respectively). Women in concordant dyads had significantly higher median endocervical quantitative Ct polymerase chain reaction values (3,032) compared with CT-infected women in discordant dyads (1013 inclusion forming units DNA equivalents per mL; P < 0.01). Among 54 Ct-concordant dyads with ompA genotype data for both members, 96.2% had identical genotypes. CONCLUSIONS Higher organism load appears associated with concordance among women. Same-genotype chlamydial concordance was high in sexual partnerships. No behavioral factors were sufficiently discriminating to guide partner services activities. Findings may help model coitus-specific transmission probabilities.

Purpose: To examine associations between depressive symptoms and dyad-level sexual risk behavior in young heterosexual dyads with sexually transmitted infection (STI). Methods: Chlamydia-positive 14-24-year-old, heterosexually active outpatients and their opposite-sex partners completed an assessment that included demographics, past and recent STI risk behaviors, and the Beck Depression Inventory (BDI). Participants in the top 25% of BDI scores within gender were categorized as depressed. Variables were created to identify dyads in which the female or male partner was depressed, as well as a measure of concordance of depression between partners. Dyad-level STI risk variables were created from the STI risk characteristics reported by each dyad member, and associations between these and the depression variables were analyzed. Results: The 130 dyads were comprised of young men and women at high STI risk. One-third of dyads had at least one depressed partner. Dyads in which the female partner was depressed had greater partner age difference, greater total number of lifetime partners, and one or more partners reporting substance use within 2 hours before sex, compared with dyads in which the female partner was not depressed. Dyads in which the male partner was depressed were more likely than the nondepressed-male dyads to report substance use before sex. All dyads in which both partners were depressed reported substance use before sex. Conclusions: In young, chlamydia-infected, heterosexual dyads, depressive symptoms, especially in women, is related to increased dyad-level STI risk, including greater partner age difference, more partners, and substance use before sex.

Trichomonas vaginalis infection is estimated to be the most widely prevalent nonviral sexually transmitted infection in the world. Wet-mount microscopy is the most common diagnostic method, although it is less sensitive than culture. The OSOM Trichomonas Rapid Test (Genzyme Diagnostics, Cambridge, Mass.) (referred to here as OSOM) is a new point-of-care diagnostic assay for T. vaginalis that uses an immunochromatographic capillary flow (dipstick) assay and provides results in 10 min. The purpose of this study was to determine the test characteristics of OSOM compared to those of a composite reference standard (CRS) comprised of wet-mount microscopy and T. vaginalis culture. This multicenter cross-sectional study enrolled sexually active women ≥18 years of age who presented with symptoms of vaginitis, exposure to T. vaginalis , or multiple sexual partners. Vaginal-swab specimens were obtained for T. vaginalis culture, wet mount, and rapid testing. The prevalence of T. vaginalis in this sample was 23.4% (105 of 449) by the CRS. The sensitivity and specificity of OSOM vaginal-swab specimens were 83.3 and 98.8%, respectively, while wet mount had a sensitivity and specificity of 71.4 and 100%, respectively, compared to the CRS. OSOM performed significantly better than wet mount ( P = 0.004) and detected T. vaginalis in samples that required 48 to 72 h of incubation prior to becoming culture positive. The performance of the rapid test was not affected by the presence of coinfections with chlamydia and gonorrhea. The OSOM Trichomonas Rapid Test is a simple, objective test that can be expected to improve the diagnosis of T. vaginalis , especially where microscopy and culture are unavailable.