Pharyngeal Neisseria Gonorrhoeae Research Articles

Antimicrobial resistance determinants in the oropharyngeal microbiome of 'men having sex with men' attending an sexually transmitted infection clinic.

'Men having sex with men' (MSM) represent a key population with a significant prevalence of pharyngeal Neisseria gonorrhoeae (NG) infections and a high rate of antimicrobial resistance genes in the pharyngeal microbiome. As NG can acquire antibiotic resistance genes from other commensal oropharyngeal bacteria, monitoring the prevalence of these resistance determinants is critical to curtail the spread of NG-resistant strains. Here, we assessed the distribution of five resistance genes (pen (A), mtr (R), gyr (A), par (C), msr (D)) in the oropharynx of 164 MSM, attending an Outpatient clinic for STI screening. The most frequently detected resistance gene was msr (D) (88.4%), followed by gyr (A) (67.1%). The distribution of resistance genes was not influenced by pharyngeal gonorrhea nor by the HIV status, whereas a younger age was associated with mtr (R) presence (p = .008). Subjects using mouthwash exhibited significantly lower levels of mtr (R) (p = .0005). Smoking habit was associated with a higher prevalence of par (C) (p = .02). A noteworthy association was observed between the presence of msr (D) gene and the use of antibiotics (p = .014). Our findings reveal an enrichment of antimicrobial resistance genes in the oropharynx of MSM. These insights could aid in the development of screening programs and antimicrobial stewardship initiatives targeting populations at heightened risk of pharyngeal gonorrhea.

Pooled Pharyngeal, Rectal, and Urine Specimens for the Point-of-Care Detection of Chlamydia trachomatis and Neisseria gonorrhoeae by Lay Providers in Key Population-Led Health Services in Thailand.

Routine testing for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) in people with heightened risk is lacking in Thailand. This study aimed to assess the performance of the Cepheid Xpert CT/NG assay, conducted by key population (KP) lay providers, for CT and NG detection on single-site and pooled specimens from the pharynx, rectum, and urine. Between August and October 2019, 188 men who have sex with men and 11 transgender women were enrolled. Participants collected urine specimens while trained KP lay providers obtained pharyngeal and rectal swabs. Compared to single-site testing with the Abbott RealTime CT/NG assay by medical technologists, the Xpert assay missed one pharyngeal NG infection out of 199 single-site specimens, giving a 93.3% sensitivity for pharyngeal NG and one missed pharyngeal NG infection out of fifty pooled specimens, giving an 88.9% sensitivity for pharyngeal NG. There was no discrepancy between the two assays for CT detection. The Cohen's Kappa coefficient of pooled specimen testing by the Xpert was 0.93 for NG and 1 for CT when compared to single-site testing by Abbott. Implementing pooled specimen testing by KP lay providers can be a cost-saving strategy to enhance the uptake of CT/NG services for populations facing increased risk.

Extra-genital Neisseria gonorrhoeae infections with genetic mutations conferring ciprofloxacin resistance among men who have sex with men and transgender women in Lima, Peru.

The increasing prevalence of drug-resistant Neisseria gonorrhoeae (NG) infections has caused great concern. Ciprofloxacin remains the empiric antimicrobial recommended to treat NG infections in Peru disregarding the susceptibility profile of circulating NG strains. We report the prevalence of individuals infected with NG strains presenting mutations in the gyrA gene that confers ciprofloxacin resistance. We conducted a descriptive study assessing extragenital swab samples collected from a cohort of men who have sex with men and transgender women in Lima, Peru. Anal and pharyngeal NG positive swabs for Aptima Combo 2 assay (Hologic Inc., USA) were used for DNA extraction. We performed TaqMan real time PCR assays to detect a point mutation at codon Ser91 of the gyrase A (gyrA) gene. From 156 individuals who had at least one positive sample for NG reported by the Aptima assay, 80 individuals had at least one amplified DNA for the gyrA gene. We found that 67 of them (84.0%) were infected with a gyrA-mutated NG strain at the Ser91 codon. We report a high prevalence of gyrA mutation conferring ciprofloxacin resistance among individuals with extragenital NG infection. Empirical treatment of NG needs to be urgently updated in Peru in concordance with international guidelines.

Pharyngeal Gonorrhea in Heterosexual Male and Female Sex Partners of Persons With Gonorrhea.

Current guidance from the US Centers for Disease Control and Prevention recommends empiric treatment for persons exposed to sexually transmitted infections, including Neisseria gonorrhoeae ( NG ). As an antimicrobial stewardship measure, some clinics now recommend a test and treat strategy, but reliance on urogenital testing only may miss cases. We conducted a descriptive analysis of pharyngeal NG infection in men who have sex with women (MSW) and women seeking care at a sexual health clinic in Seattle, WA, from February 2017 to July 2021 because of sexual contact to a partner diagnosed with gonorrhea. We also explored behavioral factors associated with pharyngeal NG positivity (by culture or nucleic acid amplification test by χ2 analysis. Among 352 NG contacts tested for urogenital or pharyngeal infection, 34% were positive for NG at ≥1 anatomic site (27% for MSW and 40% for women). Among 161 NG contacts tested at the pharynx, 30% (n = 48) were positive: 20% of 54 MSW (n = 11) and 35% (n = 37) of 107 women. If only urogenital testing were performed, 36% of MSW NG infections (n = 5) and 19% of female NG infections (n = 9) would have remained unidentified. Pharyngeal NG is relatively common among MSW and women who have been exposed to NG, and likely represents an underdiagnosed reservoir of NG infection. If empiric treatment is abandoned in favor of testing and treating, testing the throats of heterosexuals will be necessary.

Spontaneous clearance of asymptomatic anogenital and pharyngeal Neisseria gonorrhoeae: a secondary analysis from the NABOGO trial

IntroductionSpontaneous clearance of asymptomatic Neisseria gonorrhoeae (NG) does occur, but data are scarce. We aimed to assess spontaneous clearance among patients with asymptomatic anal, pharyngeal, vaginal and urethral NG infections...

Pilot study of pharyngeal Chlamydia trachomatis in HIV-positive and HIV-negative men who have sex with men.

Unlike pharyngeal Neisseria gonorrhoeae, less is known about pharyngeal Chlamydia trachomatis in men who have sex with men (MSM). We reviewed cases of pharyngeal chlamydia in MSM from January to December 2019. The overall prevalence of pharyngeal chlamydia was 75/6613 (1.13%; 95% confidence interval (CI) = 0.9-1.14). The median number of sexual partners was three, four (5%) reported throat symptoms and 20 (26%) were HIV positive. Multi-site and concomitant infection was common: rectal chlamydia [39 (52%)], urethral chlamydia [12 (16%)], early syphilis [2 (3%)] and gonorrhoea [14 (19%)]. HIV-positive MSM with pharyngeal chlamydia were older (P = 0.02) and more likely to have had previous syphilis (odds ratio = 4.9; 95% CI = 1.6-14.7; P = 0.005). Further research is needed to explore the characteristics of pharyngeal chlamydia and benefits of increased screening for asymptomatic pharyngeal chlamydia in MSM.

Treatment efficacy for pharyngeal Neisseria gonorrhoeae: a systematic review and meta-analysis of randomized controlled trials

Rising gonorrhoea rates require highly effective treatments to reduce transmission and prevent development of antimicrobial resistance. Currently the most effective treatments for pharyngeal gonorrhoea remain unclear. This review aimed to estimate treatment efficacy for pharyngeal gonorrhoea. Online bibliographic databases were searched for the period 1 January 2000 to 17 September 2019 for treatments of gonorrhoea. All randomized controlled trials (RCTs) with data on pharyngeal gonorrhoea among participants aged 15 years or above, published in English, were included. Meta-analyses (random effects) were used to estimate the treatment efficacy, defined as microbiological cure, among currently recommended monotherapies and dual therapies, previously recommended but no longer used regimens and emerging drugs under evaluation. Side effects were also summarized. The study protocol was registered on PROSPERO (CRD42020149278). There were nine studies that included 452 participants studying 19 treatment regimens. The overall treatment efficacy for pharyngeal gonorrhoea was 98.1% (95% CI: 93.8%-100%; I2 = 57.3%; P < 0.01). Efficacy was similar for single (97.1%; 95% CI: 90.8%-100.0%; I2 = 15.6%; P = 0.29) and dual therapies (98.0%; 95% CI: 91.4%-100%; I2 = 79.1%; P < 0.01). Regimens containing azithromycin 2 g or ceftriaxone were similarly efficacious. The summary efficacy estimate for emerging drugs was 88.8% (95% CI: 76.9%-97.5%; I2 = 11.2%; P = 0.34). Small sample sizes in each trial was a major limitation. Regimens containing ceftriaxone or azithromycin 2 g, alone or as part of dual therapies are the most efficacious for pharyngeal gonorrhoea. Further pharyngeal-specific RCTs with adequate sample sizes are needed.

Repeat symptomatic Neisseria gonorrhoeae infections among men who have sex with men in Bangkok, Thailand, 2006-2016.

We analyzed the incidence and predictors of symptomatic repeat Neisseria gonorrhoeae (NG) infection among men who have sex with men (MSM) enrolled in the Bangkok MSM Cohort Study. Thai MSM aged ≥18 years were enrolled during 2006–2010 and followed every four months. At baseline, participants were screened for rectal and urethral NG and Chlamydia trachomatis (CT) infections using nucleic acid amplification testing (NAAT), rectal and pharyngeal NG by culture, and pharyngeal CT by NAAT. During follow-up, symptomatic participants were tested for NG infection by NAAT and Gram stain of rectal or urethral specimens. Among 1464 participants without NG infection at the baseline visit and having at least one follow-up visit, 11.2% (164/1464) developed symptomatic NG infection, for a total of 251 infections. Symptomatic repeat NG infection occurred in 28.0% (46/164) of participants. The incidence rate was 3.9 cases per 100 person-years. Baseline predictors of repeat symptomatic NG were as follows: unknown human immunodeficiency virus (HIV) status despite history of HIV testing, previous sexually transmitted infection diagnosis by physician, insertive-only anal intercourse without a condom, amyl nitrate use at baseline, CT infection at baseline, age 18–24 years, and being a student; HIV infection at baseline or during the study period was also associated with repeat symptomatic NG infection.

High burden of chlamydia and gonorrhoea in pharyngeal, rectal and urethral sites among Thai transgender women: implications for anatomical site selection for the screening of STI

ObjectiveComprehensive data on Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections to guide screening services among transgender women (TGW) are limited. We studied the burden of CT/NG infections in pharyngeal,...

High subsequent and recurrent sexually transmitted infection prevalence among newly diagnosed HIV-positive Thai men who have sex with men and transgender women in the Test and Treat cohort.

We determined subsequent and recurrent sexually transmitted infections (STIs) among men who have sex with men (MSM) and transgender women (TGW) in the Test and Treat cohort. Thai MSM and TGW adults with previously unknown HIV status were enrolled and tested for HIV. Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and syphilis were tested at baseline, month 12, and month 24 to identify subsequent STIs (any STIs diagnosed after baseline) and recurrent STIs (any subsequent STIs diagnosed among those with positive baseline STIs). Among 448 participants, 17.8% were HIV-positive, the prevalence of subsequent STIs and recurrent STIs was 42% (HIV-positive versus HIV-negative: 66.3% versus 36.7%, p < 0.001) and 62.3% (81% versus 52.5%, p < 0.001), respectively. Common subsequent STIs by anatomical site were rectal CT infection (21.7%), rectal NG infection (13.8%), pharyngeal NG infection (13.1%), and syphilis (11.9%). HIV-positive status was associated with both subsequent STIs (adjusted hazard ratio [aHR] 2.38; 95%CI 1.64-3.45, p < 0.001) and recurrent STIs (aHR 1.83; 95%CI 1.16-2.87, p = 0.01). The results show that newly diagnosed HIV-positive MSM and TGW were at increased risk of STIs despite being in the healthcare system. STI educational counseling is necessary to improve STI outcomes among MSM and TGW in both HIV prevention and treatment programs.

The PICASSO Cohort: baseline characteristics of a cohort of men who have sex with men and male-to-female transgender women at high risk for syphilis infection in Lima, Peru

BackgroundMen who have sex with men (MSM) and male-to-female transgender women (transwomen) are disproportionately at risk of syphilis infection in Peru.MethodsFrom 2013 to 2014, MSM and transwomen seeking human immunodeficiency virus (HIV) or sexually transmitted infection (STI) testing and/or treatment were recruited into a 2-year observational cohort study to determine predictors of recently acquired syphilis infection (defined as a rapid plasma reagin [RPR] titer ≥1:16 and a reactive treponemal antibody test) in Lima, Peru. At baseline, interviewers collected sociodemographic, behavioral, and medical characteristics from participants. All cohort participants were tested for syphilis, HIV, Chlamydia trachomatis (CT), and Neisseria gonorrhoeae (NG) infection. Using cross-sectional analyses, bivariate and multivariate models were used to determine factors associated with recently acquired syphilis infection and calculate adjusted prevalence ratios.ResultsWe recruited 401 participants, 312 MSM and 89 transwomen, with median ages of 29.0 and 32.5 years old (interquartile ranges: 23.3, 37.4 and 27.2, 39.5, respectively). The prevalence of recently acquired syphilis infection at baseline was 16.8% for MSM and 6.7% for transwomen. Among MSM and transwomen, 30.1 and 33.7% were infected with HIV, 18.6 and 24.7% were infected with CT, and 14.2 and 19.1% were infected with NG, respectively. Co-infection rates among MSM with recently acquired syphilis infection included: 44.2% with HIV, 40.4% with CT (32.7% with anal CT and 7.7% with pharyngeal CT), and 19.2% with NG (11.5% with anal NG and 7.7% with pharyngeal NG). Co-infection rates among transwomen with recently acquired syphilis infection included: 66.7% with HIV, 0% with CT, and 16.7% with anal NG. In multivariate analysis among the entire cohort, recently acquired syphilis infection was independently associated with younger age (adjusted prevalence ratio [aPR] = 0.96, 95% confidence interval [CI] = 0.93–0.99), receptive role during anal sex (aPR = 2.56, 95% CI = 1.05–6.25), prior HIV diagnosis (aPR = 1.70, 95% CI = 1.11–2.61), anal CT or NG infection (aPR = 1.69, 95% CI = 1.09–2.60), and prior syphilis diagnosis (aPR = 3.53, 95% CI = 2.20–5.68).ConclusionsWe recruited a cohort of MSM and transwomen who had a high prevalence of recently acquired syphilis infection in Lima, Peru. Recently acquired syphilis infection was associated with socio-demographic characteristics, sexual risk, and sexually transmitted co-infections.

Antiseptic mouthwash against pharyngeal Neisseria gonorrhoeae: a randomised controlled trial and an in vitro study

BackgroundGonorrhoea is increasing among men who have sex with men (MSM). We aimed to determine whether Listerine, a commercial mouthwash product, has an inhibitory effect against Neisseria gonorrhoeae in a...

Is self-swabbing for gonorrhea and Chlamydia an acceptable method for screening in men who have sex with men?

Evidence-Based Answer The Aptima Combo 2 assay® (AC2), a nucleic acid amplification test (NAAT), demonstrates substantial agreement between self-collected specimens (SCS) and provider-collected specimens (PCS) testing for rectal and pharyngeal Neisseria gonorrhoeae and Chlamydia trachomatis in men who have sex with men (MSM). Selfcollection using strand displacement assays (SDA) has poor sensitivity (SOR: B, multiple diagnostic studies). The Cobas Amplicor PCR (PCR) has not been adequately proven for this indication (SOR: C, low-quality diagnostic study).

Isolated pharyngeal Neisseria gonorrhoeae in heterosexual male contacts

Pharyngeal infection with Neisseria gonorrhoeae (NG) in heterosexual men is thought to be of low prevalence and the value of routinely testing this group of patients is uncertain. We present two cases of NG, isolated only in the pharynx, in asymptomatic heterosexual male contacts. The presence of pharyngeal NG was found irrespective of direct oropharyngeal sexual exposure.

One confirmed and one suspected case of pharyngeal gonorrhoea treatment failure following 500mg ceftriaxone in Sydney, Australia

Emerging antimicrobial resistance within Neisseria gonorrhoeae (NG) is a significant global public health threat. Detection and investigation of treatment failures is a crucial component of the World Health Organisation's response to this challenge. We report the cases of two homosexual men, both treated for pharyngeal NG with 500mg intramuscular ceftriaxone, in whom a test of cure 1 week after treatment showed persisting infection. Both men denied further sexual activity. In the first case, treatment failure was confirmed, since the isolates before and after treatment were identical by auxotype, antibiogram, multilocus sequence type (MLST) and multi-antigen sequence type (NG-MAST). In the second case, the MLSTs before and after treatment were identical, but NG-MAST results were similar but not indistinguishable. These cases underline the importance of test-of-cure and molecular investigations in identifying treatment failure, but also highlight the complexity of distinguishing treatment failure from reinfection when relying on highly variable molecular targets that may be subject to drug pressure.

Ongoing Sexually Transmitted Disease Acquisition and Risk-Taking Behavior Among US HIV-Infected Patients in Primary Care: Implications for Prevention Interventions

To better understand the factors associated with HIV- and sexually transmitted disease (STD)-transmitting behavior among HIV-infected persons, we estimated STD prevalence and incidence and associated risk factors among a diverse sample of HIV-infected patients in primary care. We analyzed data from 557 participants in the SUN Study, a prospective observational cohort of HIV-infected adults in primary care in 4 US cities. At enrollment and 6 months thereafter, participants completed an audio computer-assisted self-interview about their sexual behavior, and were screened for genitourinary, rectal, and pharyngeal Neisseria gonorrhoeae and Chlamydia trachomatis infections by nucleic acid amplification testing, and for serologic evidence of syphilis. Women provided cervicovaginal samples and men provided urine to screen for Trichomonas vaginalis by polymerase chain reaction. Thirteen percent of participants had a prevalent STD at enrollment and 7% an incident STD 6 months later. The most commonly diagnosed infections were rectal chlamydia, oropharyngeal gonorrhea, and chlamydial urethritis among the men and trichomoniasis among the women. Other than trichomoniasis, 94% of incident STDs were identified in men who have sex with men. Polysubstance abuse other than marijuana, and having ≥4 sex partners in the 6 months before testing were associated with diagnosis of an incident STD. STDs were commonly diagnosed among contemporary HIV-infected patients receiving routine outpatient care, particularly among sexually active men who have sex with men who used recreational drugs. These findings underscore the need for frequent STD screening, prevention counseling, and substance abuse treatment for HIV-infected persons in care.

Should urologists care for the pharyngeal infection of Neisseria gonorrhoeae or Chlamydia trachomatis when we treat male urethritis?

Detection of Neisseria gonorrhoeae (NG) or Chlamydia trachomatis (CT) from the pharynx of women or men is not uncommon. However, there is no recommendation how urologists should care for the pharyngeal infection of men with urethritis in Japan. The aim of this study is to clarify the prevalence of NG or CT infection in the pharynx of men and to show a recommendation for urologists. The Japanese reports about the detection of NG or CT from the pharynx or the oral cavity of men in Japan are reviewed in the literature from 1990 to 2011. The prevalence of NG or CT in the pharynx was 4% or 6% in men who attended clinics, and 20% or 6% in men who were positive for NG or CT from genital specimens, respectively. Single 1-g dose ceftriaxone was recommended to treat pharyngeal NG, but no evidence was found for pharyngeal CT. There was not enough evidence for recommendation. However, when men with urethritis only caused by NG or CT are treated through the guideline of the Japanese Society of Sexually Transmitted Infection, we do not think additional tests or treatment for the pharynx are needed when a single 1-g dose ceftriaxone for gonococcal urethritis or a single 1- or 2- g dose azithromycin is prescribed for chlamydial urethritis in Japan.

Evaluation of Self-Collected Versus Clinician-Collected Swabs for the Detection of Chlamydia trachomatis and Neisseria gonorrhoeae Pharyngeal Infection Among Men Who Have Sex With Men

We evaluated self-sampling to detect pharyngeal Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infection among men who have sex with men attending a San Francisco STD clinic. The prevalence of pharyngeal NG and CT infection was 6.7% (32/480) and 1.3% (6/480), respectively. The percent agreement between self-collected and clinician-collected NG and CT specimens using nucleic acid amplification testing was 96.6% with a κ of 0.766 (95% confidence interval: 0.653-0.879) and 99.4% with a κ of 0.766 (95% confidence interval: 0.502-1.000), respectively. Acceptability was high among participants.

Incidence and Treatment Outcomes of PharyngealNeisseria gonorrhoeaeandChlamydia trachomatisInfections in Men Who Have Sex with Men: A 13‐Year Retrospective Cohort Study

This study investigated the incidence and treatment outcomes of pharyngeal Neisseria gonorrhoeae and Chlamydia trachomatis cases at a Canadian clinic that mainly serves men who have sex with men. All patients with pharyngeal N. gonorrhoeae and C. trachomatis infections detected from 1 January 1995 through 31 December 2007 were identified. Original and test-of-cure N. gonorrhoeae culture isolates were compared using antibiotic susceptibility testing and N. gonorrhoeae multiantigen sequence typing. One hundred seventy-eight cases of pharyngeal N. gonorrhoeae infection and 97 cases of pharyngeal C. trachomatis infection were identified, primarily by culture methods. The mean incidence was 1.62 and 0.81 cases per 1000 visits per year for N. gonorrhoeae and C. trachomatis infection, respectively. Poisson regression modeling demonstrated a statistically significant surge of pharyngeal N. gonorrhoeae cases in 2007 after controlling for seasonal and long-term oscillation and long-term linear trends. Among patients with pharyngeal N. gonorrhoeae and C. trachomatis infection, 60.2% and 84.3%, respectively, would have been missed by relying on urine and urethral testing. Nine percent of patients with pharyngeal N. gonorrhoeae and 4.3% of patients with pharyngeal C. trachomatis infection who underwent test-of-cure procedures had at least 1 positive result. Antibiograms were not different in 8 of 10 pretreatment and posttreatment N. gonorrhoeae isolate pairs. N. gonorrhoeae multiantigen sequence typing results were identical in 2 of these cases. Public health records documented abstinence in both individuals. Nine percent of cases with pharyngeal N. gonorrhoeae and 4.3% of cases with pharyngeal C. trachomatis infection that underwent tests of cure had positive results. Available typing results suggest antibiotic treatment failure rather than reinfection. Specific antibiotic treatment regimens for pharyngeal N. gonorrhoeae and C. trachomatis infections need to be developed and formally evaluated.

Incidence of HIV and sexually transmitted diseases (STD) in a cohort of HIV-negative men who have sex with men (MSM).

To determine the prevalence of sexually transmitted diseases (STD) and incidence of and risk factors for STD, including HIV-1, among a cohort of HIV-negative men who have sex with men (MSM). Seattle, Washington, United States. Prospective cohort of 578 HIV-negative MSM in which risk factors for acquiring a STD over 12 months follow-up were evaluated using a cumulative incidence analysis. Baseline tests obtained were: herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) Western blots, hepatitis B, and syphilis serologies; anorectal and pharyngeal Neisseria gonorrhoeae (GC) cultures; first-catch urine for leukocyte esterase (LE) and Chlamydia trachomatis (CT) ligase chain reaction (LCR). Men with a positive urine LE had urethral GC cultures obtained. The following outcomes were measured over 12 months follow-up: incident symptomatic bacterial STD (urethritis, proctitis, epididymitis), HSV-1 and HSV-2 seroconversion, and HIV-1 seroconversion. The 31 incident cases of STD (men with bacterial STD) were compared with those 489 men without symptomatic bacterial STD or seroconversion to HSV-1, HSV-2 or HIV-1 infection. Bacterial STD were found in nine participants at enrollment; there were two cases of nonchlamydial urethritis, two cases of nonchlamydial epididymitis, and five cases of asymptomatic GC infection. At enrollment, HSV-2 antibodies were detected in 149 (26.0%) of 572 men and prior hepatitis B infection in 145 (34.8%) of 417 unvaccinated men. During the 1-year of follow-up, 31 men (5.7/100 person-years) had 34 episodes of a symptomatic bacterial STD syndrome (urethritis, epididymitis or proctitis). Urethritis was the most common STD syndrome, detected in 29 men, of whom 10 had GC and 19 had nongonococcal urethritis. In the 1-year of follow-up, five participants seroconverted to HIV-1 (1.3/100 person-years), four to HSV-2 (1.0/100 person-years), and seven to HSV-1 (4.3/100 person-years). Unprotected insertive anal sex [odds ratio (OR) 2.6; 95% confidence interval (CI) 1.2-5.6]; and nitrite inhalant ('poppers') use (OR, 2.3; 95% CI, 1.0-5.0) were independently associated with incident STD. STD and HIV infection continue to be acquired even in a city with an overall low bacterial STD prevalence and among educated MSM receiving regular HIV screening and risk-reduction. Urethritis was the most common STD detected, and public health messages aimed at MSM need to emphasize safe insertive as well as receptive sexual practices.