Macrolide-Resistant Mycoplasma genitalium Impairs Clinical Improvement of Male Urethritis After Empirical Treatment.

BACKGROUND: Mycoplasma genitalium (MG) is associated with urethritis in men and could play a role in clinical outcome. We examined clinical improvement of symptoms in men receiving empirical treatment for urethritis and correlated the outcome with Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), MG, and MG macrolide resistance-associated mutations (MRAM) status. METHODS: At the sexually transmitted infection clinic in Amsterdam, the Netherlands, empirical treatment for gonococcal urethritis is 1 g ceftriaxone and for nongonococcal urethritis 1 g azithromycin. In 2018 to 2019, we tested urine samples of men with urethritis for CT, NG, and MG using transcription-mediated amplification assays. Mycoplasma genitalium-positive samples were tested for MRAM using quantitative polymerase chain reaction. Two weeks after receiving therapy, men were sent a text message inquiring after clinical improvement. RESULTS: We evaluated 2505 cases of urethritis. The positivity rates of NG, CT, and MG were 26% (648 of 2489), 29% (726 of 2489), and 23% (522 of 2288), respectively. In 768 of 2288 of the cases (34%), no causative agent was detected. Most cases were infected with a single pathogen: NG, 417 of 2288 (18%); CT, 486 of 2288 (21%); and MG, 320 of 2288 (14%). The prevalence of MRAM among MG-positives was 74% (327 of 439). For 642 (25.6%) cases, we could evaluate clinical improvement after treatment of whom 127 (20%) indicated no improvement; 9% (15 of 174) in NG cases, 18% (35 of 195) in CT cases, 14% (4 of 28) in MG wild-type cases, and 40% (38 of 94) in MG-MRAM cases. Clinical improvement in MG-MRAM cases was significantly lower compared with all other groups (P < 0.001). CONCLUSIONS: Presence of MG-MRAM is associated with lack of clinical improvement in azithromycin-treated nongonococcal urethritis.

Decreased Time to Viral Suppression After Implementation of Targeted Testing and Immediate Initiation of Treatment of Acute Human Immunodeficiency Virus Infection Among Men Who Have Sex With Men in Amsterdam.

BACKGROUND: Men who have sex with men (MSM) with acute human immunodeficiency virus (HIV) infection (AHI) are a key source of new infections. To curb transmission, we implemented a strategy for rapid AHI diagnosis and immediate initiation of combination antiretroviral therapy (cART) in Amsterdam MSM. We assessed its effectiveness in diagnosing AHI and decreasing the time to viral suppression. METHODS: We included 63 278 HIV testing visits in 2008-2017, during which 1013 MSM were diagnosed. Standard of care (SOC) included HIV diagnosis confirmation in < 1 week and cART initiation in < 1 month. The AHI strategy comprised same-visit diagnosis confirmation and immediate cART. Time from diagnosis to viral suppression was assessed for 3 cART initiation periods: (1) 2008-2011: cART initiation if CD4 < 500 cells/µL (SOC); (2) January 2012-July 2015: cART initiation if CD4 < 500 cells/µL, or if AHI or early HIV infection (SOC); and (3a) August 2015-June 2017: universal cART initiation (SOC) or (3b) August 2015-June 2017 (the AHI strategy). RESULTS: Before implementation of the AHI strategy, the proportion of AHI among HIV diagnoses was 0.6% (5/876); after implementation this was 11.0% (15/137). Median time (in days) to viral suppression during periods 1, 2, 3a, and 3b was 584 (interquartile range [IQR], 267-1065), 230 (IQR, 132-480), 95 (IQR, 63-136), and 55 (IQR, 31-72), respectively (P < .001). CONCLUSIONS: Implementing the AHI strategy was successful in diagnosing AHI and significantly decreasing the time between HIV diagnosis and viral suppression.

Enhancing help-seeking behaviour among men who have sex with men at risk for sexually transmitted infections: the syn.bas.in randomised controlled trial.

OBJECTIVES: Men who have sex with men (MSM) are at increased risk for STIs and mental disorders. Syndemic theory holds that psychosocial issues co-occur and interact, and thus increase sexual risk behaviour. Psychosocial issue identification, referral and management might reduce risk behaviour. METHODS: In the syndemic-based intervention study, an open-label randomised controlled trial, MSM were enrolled at the STI outpatient clinic of the Public Health Service of Amsterdam. We screened participants using validated questionnaires on the following problem domains: alcohol and substance use, sexual compulsivity, anxiety, depression, attention deficit hyperactivity disorder, alexithymia, intimate partner violence and childhood sexual abuse. Individuals were randomly assigned (1:1) to receive either tailored, face-to-face feedback and help-seeking advice on mental health screening, or no feedback and no help-seeking advice. Participants were followed trimonthly for a year. The primary outcomes were self-reported and confirmed help-seeking behaviour. RESULTS: We included 155 MSM: 76 in the intervention group and 79 in the control group. At inclusion, 128 participants (83.1%) scored positive in at least one problem domain. We found no significant differences in self-reported or confirmed help-seeking behaviour between the intervention and the control group: 41% vs 29% (p=0.14) and 28% vs 22% (p=0.44), respectively. There were also no differences in STI incidence and condomless anal sex acts between the two groups. CONCLUSION: Screening showed high prevalence of problems related to mental health and substance use, while tailored feedback, advice and referral did not significantly increase help-seeking behaviour. Other interventions are needed to tackle the high burden of mental disorders among MSM. TRIAL REGISTRATION NUMBER: NCT02859935.

Latent classes of sexual risk and corresponding STI and HIV positivity among MSM attending centres for sexual health in the Netherlands.

OBJECTIVES: Continuing high STI positivity among men who have sex with men (MSM) attending centres for sexual health (CSH) indicates that high-risk behaviour is ongoing. The objective of this study was to gain a better insight into risk behaviours among MSM attending CSH and to explore STI and HIV positivity by subgroups. METHODS: We used national data routinely collected during CSH consultations for this study. From September to December 2017, questions on group sex, substance use and sex with HIV-positive partners were asked at each CSH consultation. We analysed latent classes of client-related factors and sexual risk behaviour among MSM attending CSH in this period. We examined STI positivity and prevalence ratios by latent classes. RESULTS: A total of six classes were identified in order of increasing risk: 'overall low-risk behaviour' (n=2974; 22.0%), 'Western origin and multiple sex partners' (MSP) (n=4182; 30.9%), 'Non-Western origin and MSP' (n=2496; 18.5%), 'living with HIV' (n=827; 6.1%), 'group sex and HIV-positive partners' (n=1798; 13.3%) and 'group sex and chemsex' (n=1239; 9.2%). The any STI positivity ranged from 14.0% in the overall low-risk behaviour class to 35.5% in the group sex and chemsex class. HIV positivity did not differ significantly between classes. The Western origin and MSP class was largest and accounted for the majority of STI and HIV infections. CONCLUSIONS: Although STI positivity increased with increased risky behaviours, considerable STI positivity was found in all six latent classes. Comparable HIV positivity between classes indicates risk reduction strategies among subgroups engaged in risky behaviours. The differences in risk behaviour and STI positivity require preventive strategies tailored to each subgroup.

Substance Use and Sexual Risk Behavior Among Male and Transgender Women Sex Workers at the Prostitution Outreach Center in Amsterdam, the Netherlands.

OBJECTIVES: Male and transgender women sex workers (TSWs) are vulnerable for sexually transmitted infections (STIs) and human immunodeficiency virus (HIV), and substance use might be a relevant contributing factor. We assessed sociodemographic characteristics and substance use among sex workers; divided into 3 groups: Transgender women sex workers, male sex workers who have sex with men only or also with females (MSW-M), male sex workers who have sex with females only (MSW-F). METHODS: A survey on substance use and sexual (risk) behavior was offered during routine STI screening at the Prostitution and Health Centre (P&G292) in Amsterdam. Bacterial STI positivity (chlamydia (including lymphogranuloma venereum), gonorrhea, and/or infectious syphilis), and substance use were compared (χ test, Fisher exact test). RESULTS: From 2014 until 2015, 99 (60.4%) of 164 eligible visitors participated (n = 69 MSW-M [69.7%], n = 15 TSW [15.2%], and n = 15 MSW-F [15.2%]). Transgender women sex workers reported the highest number of sex partners in the previous 6 months (median: MSW-M 60 vs. TSW 300 vs. MSW-F 12; P < 0.001). The 3 groups did not differ in having condomless anal or oral sex. Bacterial STI positivity was 29.0% in MSW-M, 26.7% in TSW, and 13.3% in MSW-F (P = 0.56). Three new HIV infections were diagnosed, all in MSW-M, whereas 20.3% of MSW-M and 20.0% of TSW were known HIV-positive compared with none of MSW-F (P = 0.14). Illicit substance use during working time in <6 months was 40.5% among MSW-M, 40.0% among TSW, and 20.0% among MSW-F (P = 0.02). The most reported reason for substance use was: "sex work becomes physically easier." CONCLUSIONS: Bacterial STI positivity and illicit substances use during work were high in all 3 sex worker groups, emphasizing the importance of combined and targeted interventions. In-depth qualitative research is needed to better understand intentions and reasons for substance use.

Evaluation of the Hepatitis C Testing Strategy for Human Immunodeficiency Virus-Positive Men Who Have Sex With Men at the Sexually Transmitted Infections Outpatient Clinic of Amsterdam, the Netherlands.

INTRODUCTION: As the incidence of hepatitis C virus (HCV) infections remains high among human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) an HCV testing strategy was introduced at the sexually transmitted infections (STI) clinic in Amsterdam in 2017. We aimed to evaluate this HCV testing strategy. METHODS: The HIV-positive MSM and transgender women (TGW) were eligible for HCV testing (anti-HCV and HCV ribonucleic acid) at the STI clinic if they did not visit their HIV clinician in the 3 months before the consultation and had not been tested for HCV at the STI clinic in the previous 6 months. All eligible individuals were administered the 6 questions on risk behavior of the HCV-MSM observational study of acute infection with hepatitis C (MOSAIC) risk score; a risk score of 2 or greater made a person eligible for testing. RESULTS: From February 2017 through June 2018, 1015 HIV-positive MSM and TGW were eligible for HCV testing in 1295 consultations. Eleven active HCV infections (HCV ribonucleic acid positive) were newly diagnosed (positivity rate, 0.9%; 95% confidence interval [CI], 0.4-1.5%). Sensitivity and specificity of the HCV-MOSAIC score for newly diagnosed active HCV infections were 80.0% (95% CI, 49.0-94.3%) and 53.7% (95% CI, 50.8-56.5%), respectively. If an HCV-MOSAIC score of 2 or greater were used to determine whom to test, 46.6% of individuals currently tested for HCV would be eligible for testing. CONCLUSIONS: Using the new HCV testing strategy, HCV testing was done in 1295 consultations with HIV-positive MSM and TGW in 17 months. We newly diagnosed 11 active HCV infections. The HCV-MOSAIC risk score could reduce the number of tests needed, but some active HCV infections will be missed.

Microscopic examination of Gram-stained smears for anogenital gonorrhoea in men who have sex with men is cost-effective: evidence from a modelling study.

OBJECTIVE: To assess the cost-effectiveness of three testing strategies with or without light microscopic Gram-stained smear (GSS) evaluation for the detection of anogenital gonorrhoea among men who have sex with men (MSM) at the Amsterdam STI clinic using a healthcare payer perspective. METHODS: Three testing strategies for MSM were compared: (1) GSS in symptomatic MSM only (currently practised strategy), (2) no GSS and (3) GSS in symptomatic and asymptomatic MSM. The three testing protocols include testing with nucleic acid amplification test to verify the GSS results in (1) and (3), or as the only test in (2). A transmission model was employed to calculate the influence of the testing strategies on the prevalence of anogenital gonorrhoea over 10 years. An economic model combined cost data on medical consultations, tests and treatment and utility data to estimate the number of epididymitis cases and quality-adjusted life years (QALY) associated with gonorrhoea. Incremental cost-effectiveness ratios (ICERs) for the testing scenarios were estimated. Uncertainty and sensitivity analyses were performed. RESULTS: No GSS testing compared with GSS in symptomatic MSM only (current strategy) resulted in nine extra epididymitis cases (95% uncertainty interval (UI): 2-22), 72 QALYs lost (95% UI: 59-187) and €7300 additional costs (95% UI: -€185 000 (i.e.cost-saving) to €407 000) over 10 years. GSS testing in both symptomatic and asymptomatic MSM compared with GSS in symptomatic MSM only resulted in one prevented epididymitis case (95% UI: 0-2), 1.1 QALY gained (95% UI: 0.1-3.3), €148 000 additional costs (95% UI: €86 000 to-€217 000) and an ICER of €177 000 (95% UI: €67 000-to €705 000) per QALY gained over 10 years. The results were robust in sensitivity analyses. CONCLUSIONS: GSS for symptomatic MSM only is cost-effective compared with no GSS for MSM and with GSS for both symptomatic and asymptomatic MSM.

Impact of point-of-care management on the transmission of anogenital gonococcal infections among men who have sex with men in Amsterdam: a mathematical modelling and cost-effectiveness study.

OBJECTIVE: Point-of-care (POC) management may avert ongoing transmissions occurring between testing and treatment or due to loss to follow-up. We modelled the impact of POC management of anogenital gonorrhoea (with light microscopic evaluation of Gram stained smears) among men who have sex with men (MSM) on gonorrhoea prevalence and testing and treatment costs. METHODS: Data concerning costs and sexual behaviour were collected from the STI clinic of Amsterdam. With a deterministic model for gonorrhoea transmission, we calculated the prevalence of gonorrhoea in MSM in Amsterdam and the numbers of consultations at our clinic over 5 years, in three testing scenarios: POC for symptomatic MSM only (currently routine), POC for all MSM and no POC for MSM. RESULTS: Among MSM, 34.7% (109/314) had sexual contacts in the period between testing and treatment, of whom 22.9% (25/109) had unprotected anal intercourse. Expanding POC testing from symptomatic MSM to all MSM could result in an 11% decrease (IQR, 8%-15%) in gonorrhoea prevalence after 5 years and a cost increase of 8.6% (€2.40) per consultation and €86 118 overall (+8.3%). Switching from POC testing of symptomatic MSM to no POC testing could save €1.83 per consultation (6.5%) and €54 044 (-5.2%) after 5 years with a 60% (IQR, 26%-127%) gonorrhoea prevalence increase. Overtreatment was 2.1% (30/1411) with POC for symptomatic MSM only and 4.1% (68/1675) with POC for all MSM. CONCLUSIONS: In the Amsterdam setting, possible abandonment of POC testing of symptomatic MSM because of budget cuts could result in a considerable increase in gonorrhoea prevalence against a reduction in costs per consultation. Expanding POC testing to all MSM could result in a modest reduction in prevalence and a cost increase. While the costs and outcomes depend on specific local characteristics, the developed framework of this study is useful to evaluate POC management in other settings.

Chemsex Among Men Who Have Sex With Men: a Sexualized Drug Use Survey Among Clients of the Sexually Transmitted Infection Outpatient Clinic and Users of a Gay Dating App in Amsterdam, the Netherlands.

OBJECTIVES: Chemsex (i.e., drug use during sex) is practiced by some men who have sex with men (MSM) and is associated with high-risk behavior. In a cross-sectional study at the sexually transmitted infection (STI) clinic of Amsterdam, we explored chemsex practices, risk behavior, and STI prevalence. METHOD: A survey on chemsex (γ-hydroxybutyrate, crystal methamphetamine, and/or mephedrone) was offered to clinic clients during routine STI screening and to Amsterdam users of a gay online dating app. Associations were assed using χ test and multivariable regression. RESULTS: Chemsex in the past 6 months was practiced by 866 (17.6%) of 4925 MSM clients and by 159 (1.5%) of 10857 non-MSM clients. Among gay dating app users, the proportion that reported chemsex engagement was higher than among MSM visiting the STI clinic (29.3% [537/1832] vs. 17.6%; P < 0.001). Chemsex was a significant risk factor for bacterial STI in HIV-negative MSM visiting the STI clinic (adjusted odd ratio, 1.5; 95% confidence interval, 1.2-1.8), but not in HIV-positive MSM. A majority practiced chemsex once a month or less, and 87.0% reported sex without drug use in the past month. CONCLUSIONS: In Amsterdam, chemsex is frequently practiced and significantly associated with bacterial STI in HIV-negative MSM but not in HIV-positive MSM. Future prevention strategies to reduce STI incidence should especially target HIV-negative MSM engaging in chemsex.

Sender and Receiver Acceptability and Usability of an Online Partner Notification Tool for Sexually Transmitted Infection in the Netherlands.

Users (index patients with a verified sexually transmitted infection and notified partners) rated the health care provider-initiated Internet-based partner notification application Suggestatest.nl acceptable and usable. Both groups were less positive about Suggestatest.nl to notify/get notified of HIV than other sexually transmitted infection. An anonymous notification was perceived less acceptable.

Stable Low Hepatitis C Virus Antibody Prevalence Among HIV-Negative Men Who Have Sex With Men Attending the Sexually Transmitted Infection Outpatient Clinic in Amsterdam, 2007 to 2017.

BACKGROUND: In response to the increased hepatitis C virus (HCV) prevalence recently found among participants of the Amsterdam preexposure prophylaxis demonstration project, we evaluated HCV prevalence over time and the performance of the HCV-MOSAIC risk score for detection of HCV infection in HIV-negative men who have sex with men (MSM) attending the Amsterdam sexually transmitted infection (STI) clinic. METHODS: In October 2016, HIV-negative MSM were tested for anti-HCV and HCV RNA and completed the HCV-MOSAIC risk score. Anti-HCV prevalence was compared with that found in cross-sectional studies at the Amsterdam STI clinic (2007-2017). The time trend in HCV prevalence was modeled via logistic regression. The performance of the HCV-MOSAIC risk score, adjusted to identify prevalent HCV infection, was evaluated by calculating sensitivity and specificity. RESULTS: Of 504 HIV-negative MSM tested in October 2016, 5 were anti-HCV positive (1.0%, 95% confidence interval [CI], 0.4%-2.3%) and all were HCV RNA negative. Sensitivity and specificity of the adjusted HCV-MOSAIC risk score for prevalent infection were 80.0% (95% CI, 37.6%-96.4%) and 56.1% (95% CI, 51.7%-60.4%), respectively. The overall anti-HCV prevalence among 3264 HIV-negative MSM participating in cross-sectional studies at the Amsterdam STI clinic (2007-2017) was 0.8% (95% CI, 0.5%-1.2%) and did not change over time (P = 0.55). CONCLUSIONS: Anti-HCV prevalence among HIV-negative MSM attending the Amsterdam STI clinic in October 2016 was 1.0% and remained stable over time. We would therefore not recommend routine HCV screening of HIV-negative MSM at the STI clinic. However, given the increased prevalence among MSM using preexposure prophylaxis, periodic monitoring of HCV prevalence remains important.

Sexually Transmitted Infection Positivity Rate and Treatment Uptake Among Female and Male Sexual Assault Victims Attending The Amsterdam STI Clinic Between 2005 and 2016.

BACKGROUND: Victims could become infected with sexually transmitted infections (STIs) during a sexual assault. Several guidelines recommend presumptive antimicrobial therapy for sexual assault victims (SAVs). We assessed the STI positivity rate and treatment uptake of female and male SAVs at the Amsterdam STI clinic. METHODS: Sexual assault victims answered assault-related questions and were tested for bacterial STI (chlamydia, gonorrhea, and syphilis), hepatitis B, and HIV during their initial visits. Sexual assault victim characteristics were compared with non-SAV clients. Backward multivariable logistic regression analysis was conducted to assess whether being an SAV was associated with a bacterial STI. The proportion of those returning for treatment was calculated. RESULTS: From January 2005 to September 2016, 1066 (0.6%) of 168,915 and 135 (0.07%) of 196,184 consultations involved female and male SAVs, respectively. Among female SAVs, the STI positivity rate was 11.2% versus 11.6% among non-SAVs (P = 0.65). Among male SAVs, the STI positivity rate was 12.6% versus 17.7% among non-SAVs (P = 0.12). In multivariable analysis, female SAVs did not have increased odds for an STI (odds ratio 0.94; 95% confidence interval, 0.77-1.13), and male SAVs had significantly lower odds for an STI (odds ratio, 0.60; 95% confidence interval, 0.36-0.98). Of SAVs requiring treatment, 89.0% (female) and 92.0% (male) returned. CONCLUSIONS: The STI positivity rate among female SAVs was comparable with female non-SAVs, but male SAVs had lower odds for having a bacterial STI than did male non-SAVs, when adjusting for confounders. The return rate of SAV for treatment was high and therefore does not support the recommendations for presumptive therapy.

What Is the Optimal Time to Retest Patients With a Urogenital Chlamydia Infection? A Randomized Controlled Trial.

BACKGROUND: Chlamydia trachomatis is a common, often recurring sexually transmitted infection, with serious adverse outcomes in women. Current guidelines recommend retesting after a chlamydia infection, but the optimum timing is unknown. We assessed the optimal retest interval after urogenital chlamydia treatment. METHODS: A randomized controlled trial among urogenital chlamydia nucleic acid amplification test positive heterosexual clients of the Amsterdam sexually transmitted infection clinic. After treatment, patients were randomly assigned for retesting 8, 16, or 26 weeks later. Patients could choose to do this at home (and send a self-collected sample by mail) or at the clinic. Retest uptake and chlamydia positivity at follow-up were calculated. RESULTS: Between May 2012 and March 2013, 2253 patients were included (45% men; median age, 23 years; interquartile range, 21-26). The overall uptake proportion within 35 weeks after the initial visit was significantly higher in the 8-week group (77%) compared with the 16- and 26-week groups (67% and 64%, respectively, P < 0.001), and the positivity proportions among those retested were comparable (P = 0.169). The proportion of people with a diagnosed recurrent chlamydia infection among all randomized was similar between the groups (n = 69 [8.6%], n = 52 [7.4%], and n = 69 [9.3%]; P = 0.4). CONCLUSIONS: Patients with a recent urogenital chlamydia are at high risk of recurrence of chlamydia and retesting them is an effective way of detecting chlamydia cases. We recommend inviting patients for a re-test 8 weeks after the initial diagnosis and treatment.

Ethnic differences in infectious burden and the association with metabolic risk factors for cardiovascular disease: a cross-sectional analysis.

BACKGROUND: The burden of metabolic risk factors for cardiovascular disease (CVD), such as type 2 diabetes, elevated cholesterol and hypertension, is unequally distributed across ethnic groups. Recent findings suggest an association of infectious burden (IB) and metabolic risk factors, but data from ethnic groups are scarce. Therefore, we investigated ethnic differences in IB and its association with metabolic risk factors. METHODS: We included 440 Dutch, 320 Turkish and 272 Moroccan participants, 18-70 years, of the 2004 general health survey in Amsterdam, the Netherlands. IB was defined by seropositivity to the sum of 6 infections: Herpes Simplex Virus 1 and 2; Hepatitis A, B and C; and Helicobacter pylori. Associations between IB categories 4-6 (high), 3 (intermediate) and 0-2 (low) infections and metabolic risk factors were assessed by logistic regression. Finally, we determined the contribution of IB to the association between ethnicity and the metabolic risk factors by comparing adjusted logistic regression models with and without IB categories. RESULTS: A high IB was more frequently observed among the Turkish and Moroccans than among the Dutch. After adjustment for age, sex, ethnicity, educational level, physical activity and body mass index, high IB was associated with type 2 diabetes (odds ratio high vs low IB (OR) =2.14, 95%-confidence interval (CI) 1.05-4.36). The association was weaker and not statistically significant, for elevated cholesterol (OR = 1.39, 95%-CI 0.82-2.34) and hypertension (OR = 1.49, 95%-CI 0.88-2.51). IB attenuated ethnic differences particularly for type 2 diabetes. CONCLUSIONS: Our study showed that Turkish and Moroccan adults in Amsterdam have a higher IB than Dutch adults, which was associated with the differences in type 2 diabetes. Due to the cross-sectional nature of the study, we cannot draw a conclusions with regards to the time-sequence of cause and effect. Nevertheless, the findings ask for further research into the nature of association of IB with metabolic risk factors in a longitudinal setting.

Decreased Azithromycin Susceptibility of Neisseria gonorrhoeae Isolates in Patients Recently Treated with Azithromycin.

Background: Increasing azithromycin usage and resistance in Neisseria gonorrhoeae threatens current dual treatment. Because antimicrobial exposure influences resistance, we analyzed the association between azithromycin exposure and decreased susceptibility of N. gonorrhoeae. Methods: We included N. gonorrhoeae isolates of patients who visited the Amsterdam STI Clinic between 1999 and 2013 (t0), with another clinic visit in the previous 60 days (t-1). Exposure was defined as the prescription of azithromycin at t-1. Using multivariable linear regression, we assessed the association between exposure and azithromycin minimum inhibitory concentration (MIC). Whole genome sequencing (WGS) was performed to produce a phylogeny and identify multilocus sequence types (MLST), N. gonorrhoeae multiantigen sequence types (NG-MAST), and molecular markers of azithromycin resistance. Results: We included 323 isolates; 212 were unexposed to azithromycin, 14 were exposed ≤30 days, and 97 were exposed between 31 and 60 days before isolation. Mean azithromycin MIC was 0.28 mg/L (range, <0.016-24 mg/L). Linear regression adjusted for age, ethnicity, infection site, and calendar year showed a significant association between azithromycin exposure ≤30 days and MIC (ß, 1.00; 95% confidence interval, 0.44-1.56; P = .002). WGS was performed on 31 isolates: 14 unexposed, 14 exposed to azithromycin ≤30 days before isolation, and 3 t-1 isolates. Exposure to azithromycin was significantly associated with A39T or G45D mtrR mutations (P = .046) but not with MLST or NG-MAST types. Conclusions: The results suggest that frequent azithromycin use in populations at high risk of contracting N. gonorrhoeae induces an increase in MIC and may result in resistance.

Incidence of repeat testing and diagnoses of Chlamydia trachomatis and Neisseria gonorrhoea in swingers, homosexual and heterosexual men and women at two large Dutch STI clinics, 2006-2013.

OBJECTIVE: Swingers, that is, heterosexuals who as a couple have sex with others, including group sex and bisexual behaviour, are an older-aged risk group for STIs. Here, we report on their repeat testing (reattendance) and STI yield compared with other heterosexuals and men who have sex with men (MSM, homosexual men) at two Dutch STI clinics. METHODS: Swingers are routinely (since 2006, South Limburg, registration-completeness: 99%) or partially (since 2010, Amsterdam, registration-completeness: 20%) included in the clinic patient registries. Data (retrospective cohort) are analysed to assess incidence (per 100 person-years (PY)) of reattendance and STI (Chlamydia trachomatis (CT) and/or Neisseria gonorrhoeae (NG)) and associated factors calculating HRs. RESULTS: In South Limburg 7714 and in Amsterdam 2070 swinger consultations were identified. Since 2010, swingers' incidence of reattendance was 48-57/100 PY. Incidence was lower in MSM (30-39/100 PY, HR 0.56; 95% CI 0.51 to 0.61, South Limburg; HR 0.88; 95% CI 0.80 to 0.96, Amsterdam), heterosexual men (8-14/100 PY, HR 0.16; 95% CI 0.15 to 0.17, South Limburg; HR 0.33; 95% CI 0.30 to 0.36, Amsterdam) and women (13-20/100 PY, HR 0.56; 95% CI 0.51 to 0.61, South Limburg; HR 0.46; 95% CI 0.42 to 0.51, Amsterdam). Swingers' STI incidence at reattendance was 11-12/100 PY. Incidence was similar in heterosexual men (14-15/100 PY; HR 1.19; 95% CI 0.90 to 1.57, South Limburg; HR 1.20; 95% CI 0.91 to 1.59, Amsterdam) and women (12-14/100 PY; HR 1.14; 95% CI 0.88 to 1.49, South Limburg; HR 0.98; 95% CI 0.74 to 1.29, Amsterdam) and higher in MSM (18-22/100 PY; HR 1.59; 95% CI 1.19 to 2.12, South Limburg; HR 1.80; 95% CI 1.36 to 2.37, Amsterdam). Risk factors for STI incidence were partner-notified (contact-tracing), symptoms and previous STI. Swingers' positivity at any clinic attendance was 3-4% for NG (ie, higher than other heterosexuals) and 6-8% for CT (ie, lower than heterosexuals overall but higher than older heterosexuals). CONCLUSIONS: Systematic identification reveals that swingers are part of the normal STI clinic populations. They frequently repeat test yet are likely under-recognised in clinics which not routinely ask about swinging. Given swingers' notable STI rates, usage of services is warranted, although use may be restricted, that is, to those with an STI risk factor (as did Dutch clinics). As swingers have dense sexual networks, enhancing contact-tracing may have high impact.

Low Prevalence of Urethral Lymphogranuloma Venereum Infections Among Men Who Have Sex With Men: A Prospective Observational Study, Sexually Transmitted Infection Clinic in Amsterdam, the Netherlands.

In contrast to anorectal lymphogranuloma venereum (LGV), few urogenital LGV cases are reported in men who have sex with men. Lymphogranuloma venereum was diagnosed in 0.06% (7/12,174) urine samples, and 0.9% (109/12,174) anorectal samples. Genital-anal transmission seems unlikely the only mode of transmission. Other modes like oral-anal transmission should be considered.

False-negative type-specific glycoprotein G antibody responses in STI clinic patients with recurrent HSV-1 or HSV-2 DNA positive genital herpes, The Netherlands.

OBJECTIVES: Herpes simplex virus (HSV) type-discriminating antibody tests (glycoprotein G (gG) directed) are used to identify naïve persons and differentiate acute infections from recurrences. We studied test characteristics of three commercially available antibody tests in patients with recurrent (established by viral PCR tests) herpes simplex virus type 1 (HSV-1) or herpes simplex virus type 2 (HSV-2) genital herpes episodes. METHODS: Serum samples (at minimum 3 months after t=0) were examined for the presence of gG-1-specific or gG-2-specific antibodies using the HerpeSelect 1 and 2 Immunoblot IgG, the HerpeSelect 1 and 2 enzyme linked immunoassays IgG and the LIAISON HSV-1 and HSV-2 IgG indirect chemiluminescence immunoassays. RESULTS: The immunoblot was HSV-1 positive in 70.6% (95% CI 44.0% to 89.7%), the LIAISON in 88.2% (95% CI 63.5% to 98.5%) and the ELISA in 82.4% (95% CI 56.6% to 96.2%) of the 17 patients with a recurrent HSV-1 episode. From 33 patients with a recurrent HSV-2 episode, the immunoblot was HSV-2 positive in 84.8% (95% CI 68.1% to 94.9%), the LIAISON in 69.7% (95% CI 51.3% to 84.4%) and the ELISA in 84.8% (95% CI 68.1% to 94.9%). Among 15/17 (88.2%; 95% CI 63.5% to 98.5%) patients with HSV-1 and 30/33 (90.1%; 95% CI 75.7% to 98.1%) patients with HSV-2, HSV-1 or HSV-2 antibodies, respectively, were detected in at least one of the three antibody tests. CONCLUSIONS: Commercial type-specific gG HSV-1 or HSV-2 antibody assays were false negative in 12-30% of patients with recurrent HSV-1 or HSV-2 DNA positive genital lesions. The clinical and epidemiological use of type-specific HSV serology can be hampered by false-negative results, especially if based on a single test.

Young Low-Risk Heterosexual Clients Prefer a Chlamydia Home Collection Test to a Sexually Transmitted Infection Clinic Visit in Amsterdam, the Netherlands, A Cross-Sectional Study.

BACKGROUND: Home-based self-collection of specimens for urogenital and anorectal chlamydia testing has been proven feasible and acceptable. We studied the efficiency of chlamydia home collection kits for young low-risk persons to optimize care at the Amsterdam sexually transmitted infection (STI) clinic. METHODS: Low-risk heterosexual persons under 25 years submitting an appointment request online were offered 3 different ways of chlamydia testing: (1) receiving a home collection kit, (2) coming to the clinic without, or (3) with sexual health counseling. The collection kit was sent to the client by surface mail and was used to self-collect a vaginal swab or urine sample (men). This sample was sent back to the laboratory for testing and the results could be retrieved online. Testing for gonorrhea, syphilis, and human immunodeficiency virus was indicated after testing chlamydia-positive. RESULTS: Between September 2012 until July 2013, from 1804 online requests, 1451 (80%) opted for the home collection kit, 321 (18%) preferred an appointment at the clinic without, and 32 (2%) with sexual health counseling. Of the requested home collection kits, 88% were returned. Chlamydia was diagnosed in 6.0% of the clients receiving a home collection kit, and none of the chlamydia-positive clients tested positive for other STI. CONCLUSIONS: Home collection is the preferred method for most young low-risk heterosexual clients who seek STI care. With a high compliance to collect and return the samples, home collection can be used as a tool to increase efficiency and dedicate STI clinic workers efforts to those at highest risk.

Spontaneous pharyngeal Chlamydia trachomatis RNA clearance. A cross-sectional study followed by a cohort study of untreated STI clinic patients in Amsterdam, The Netherlands.

OBJECTIVES: Pharyngeal Chlamydia trachomatis (chlamydia) might contribute to ongoing chlamydia transmission, yet data on spontaneous clearance duration are rare. We examined the prevalence, spontaneous clearance, chlamydial DNA concentration and genotypes of pharyngeal chlamydia among clinic patients with sexually transmitted infection (STI). METHODS: Female patients at high risk for an STI who reported active oral sex and male patients who have sex with men (MSM) were screened for pharyngeal chlamydia RNA using a nucleic acid amplification test. A repeat swab was obtained to evaluate spontaneous clearance in untreated patients with pharyngeal chlamydia. Quantitative chlamydia DNA load was determined by calculating the chlamydia/human cell ratio. RESULTS: Pharyngeal chlamydia was detected in 148/13 111 (1.1%) MSM and in 160/6915 (2.3%) women. 53% of MSM and 32% of women with pharyngeal chlamydia did not have a concurrent anogenital chlamydia infection. In 16/43 (37%) MSM and in 20/55 (36%) women, the repeat pharyngeal swab was negative (median follow-up 10 days, range 4-58 days). Patients with an initial chlamydial DNA concentration above the median were less likely to clear. Of 23 MSM with pharyngeal chlamydia who had sex with a lymphogranuloma venereum (LGV)-positive partner recently or in the past, two were LGV biovar positive (8.7%). CONCLUSIONS: The pharynx is a reservoir for chlamydia and LGV, and may play a role in ongoing transmission. Although delay in ribosomal RNA decline after resolution of the infection might have led to an underestimation of spontaneous clearance, in high-risk STI clinic patients, testing the pharynx for chlamydia should be considered.