Pharyngeal Chlamydia trachomatis in Men Who Have Sex With Men (MSM) in The Netherlands: A Large Retrospective Cohort Study.

Pharyngeal Chlamydia trachomatis (CT) was diagnosed in 1.2% and pharyngeal-only CT in 0.5% of routinely universally tested men who have sex with men (MSM). In these 3-anatomic-site tested MSM, pharyngeal-only CT comprised 4.8% of all CT. The low positivity of pharyngeal-only CT indicates low public health impact of pharyngeal CT.

Routine universal testing versus selective or incidental testing for oropharyngeal Chlamydia trachomatis in women in the Netherlands: a retrospective cohort study.

BACKGROUND: Pharyngeal Chlamydia trachomatis in women might contribute to autoinoculation and transmission to sexual partners. Data for effectiveness of different testing practices for pharyngeal C trachomatis are scarce. We therefore aimed to assess the prevalence of pharyngeal C trachomatis, determinants, and effectiveness of different testing practices in women. METHODS: We did a retrospective cohort study, in which surveillance data for all women visiting sexually transmitted infection clinics in all regions in the Netherlands between Jan 1, 2008, and Dec 31, 2017, were used. We collected consultation-level data and individual-level data from 2016 onwards for sociodemographic characteristics, sexual behaviour in the past 6 months, self-reported symptoms, and STI diagnoses. The primary outcome was the positivity rate of pharyngeal C trachomatis infection compared between routine universal testing (>85% tested pharyngeally per clinic year), selective testing (5-85% tested pharyngeally per clinic year), and incidental testing (<5% pharyngeally tested per clinic year). We calculated the number of missed infections by extrapolating the positivity rate assessed by routine universal testing to all selectively tested women. We used multivariable generalised estimating equations logistic regression analyses to assess independent risk factors for pharyngeal C trachomatis and used the assessed risk factors as testing indicators for comparing alternative testing scenarios. FINDINGS: Between Jan 1, 2008, and Dec 31, 2017, a total of 550 615 consultations with at least one C trachomatis test was recorded, of which 541 945 (98·4%) consultations (including repeat visits) were included in this analysis. Pharyngeal C trachomatis positivity was lower in the routine universal testing group than in the selective testing group (1081 [2·4%; 95% CI 2·2-2·5] of 45 774 vs 3473 [2·9%; 2·8-3·0] of 121 262; p<0·0001). The positivity rate was also higher among consultations done in the incidental testing group (44 [4·1%; 95% CI 3·1-5·5] of 1073; p<0·0001) than in the routine universal testing group. Based on extrapolation, selective testing would have hypothetically missed 64·4% (95% CI 63·5-65·3; 6363 of 9879) of the estimated total of C trachomatis infections. The proportion of pharyngeal-only C trachomatis was comparable between routinely universally tested women (22·9%) and selectively tested women (20·4%), resulting in a difference of 2·5% (95% CI -0·3 to 5·3; p=0·07). When using risk factors for pharyngeal C trachomatis as testing indicators, 15 484 (79·6%) of 19 459 women would be tested to detect 398 (80·6%) of 494 infections. INTERPRETATION: No optimal testing scenario was available for pharyngeal C trachomatis, in which only a selection of high-risk women needs to be tested to find most pharyngeal C trachomatis infections. The relative low prevalence of pharyngeal-only C trachomatis (0·5%) and probably limited clinical and public health effect do not provide support for routine universal testing. FUNDING: Public Health Service South Limburg.

Culture-Independent Genotyping Revealed 3 Strain Clusters in a Potential Neisseria gonorrhoeae Outbreak in Young Heterosexuals (<25 Years), the Netherlands, October 2017 to March 2019.

BACKGROUND: Investigation was undertaken to determine the genetic relatedness of Neisseria gonorrhoeae (NG) isolates of young (<25 years) heterosexuals of a potential outbreak from October 2017 to March 2019 in South-Limburg, the Netherlands. METHODS: Data and residual sample material of routine diagnostics were retrieved for outbreak cases (78/81), young heterosexuals at baseline (January 2016 to September 2017, n = 30), and men who have sex with men (2018, n = 47). Total DNA was isolated, and NG was genotyped using culture-free NG multiantigen sequence typing. Sanger sequence data were used to construct a phylogenetic tree. Cases of outbreak clusters were geographically mapped, and descriptive analyses were performed on patient characteristics, comparing these clusters. RESULTS: Outbreak investigation showed 81 cases of young heterosexuals between October 2017 and March 2019 (4.5 per month) compared with 30 between January 2016 and September 2017 (1.4 per month), which was considered as baseline. Culture-independent genotyping of NG was performed to assess the genetic relatedness, as only 21 outbreak cases were culture confirmed. This revealed 3 independent outbreak clusters G2 (n = 18), G13113 (n = 11), and GNewST (n = 24). None of the clusters were geographically linked or introduced by bridging with men who have sex with men networks. Number of sex partners reported by men and Chlamydia trachomatis coinfection were associated with clusters G2 and GNewST, respectively. CONCLUSIONS: Culture-independent typing proved to be essential to identify the 3 outbreak clusters. However, targeted interventions were difficult because information on sex partners was limited. Therefore, prospective culture-independent typing could be used for early outbreak detection and aid in transmission prevention.

High rate of loss to follow-up and virological non-suppression in HIV-infected children on antiretroviral therapy highlights the need to improve quality of care in South Africa.

Provision of high-quality care and ensuring retention of children on antiretroviral therapy (ART) are essential to reduce human immunodeficiency virus (HIV)-associated morbidity and mortality. Virological non-suppression (≥1000 viral copies/ml) is an indication of suboptimal HIV care and support. This retrospective cohort study included ART-naïve children who initiated first-line ART between July 2015 and August 2017 in Johannesburg and rural Mopani district. Of 2739 children started on ART, 29.5% (807/2739) were lost to care at the point of analysis in August 2018. Among retained children, overall virological non-suppression was 30.2% (469/1554). Virological non-suppression was associated with higher loss to care 30.3% (229/755) compared with suppressed children (9.7%, 136/1399, P < 0.001). Receiving treatment in Mopani was associated with virological non-suppression in children under 5 years (adjusted odds ratio (aOR) 1.7 (95% confidence interval (CI) 1.1-2.4), 5-9 years (aOR 1.8 (1.1-3.0)) and 10-14 years (aOR 1.9 (1.2-2.8)). Virological non-suppression was associated with lower CD4 count in children 5-9 years (aOR 2.1 (1.1-4.1)) and 10-14 years (aOR 2.1 (1.2-3.8)). Additional factors included a shorter time on ART (<5 years aOR 1.8-3.7 (1.3-8.2)), and male gender (5-9 years, aOR1.5 (1.01-2.3)), and receiving cotrimoxazole prophylaxis (10-14 years aOR 2.0 (1.2-3.6)). In conclusion, virological non-suppression is a factor of subsequent programme loss in both regions, and factors affecting the quality of care need to be addressed to achieve the third UNAIDS 90 in paediatric HIV.

Routine universal testing versus selective or incidental testing for oropharyngeal Neisseria gonorrhoeae in women in the Netherlands: a retrospective cohort study.

BACKGROUND: Women are not routinely tested for oropharyngeal Neisseria gonorrhoeae. At present, selective testing based on sexual behaviour or risk groups is advocated by international guidelines. Many oropharyngeal infections are asymptomatic and thus remain undetected, establishing a reservoir for ongoing transmission. Data on effectiveness of routine testing are scarce, thus we aimed to assess the optimal testing strategy for oropharyngeal N gonorrhoeae in women. METHODS: In this retrospective cohort study, we used surveillance data obtained from all sexually transmitted infection (STI) clinics in the Netherlands between Jan 1, 2008, and Dec 31, 2017. We collected consultation-level data, and individual-level patient data from 2016 onwards, on sociodemographic characteristics, sexual behaviour in the past 6 months, self-reported symptoms, and STI diagnoses. We compared the prevalence of oropharyngeal N gonorrhoeae between women who attended clinics that offered routine universal testing (defined as >85% of women tested per clinic-year) and women who attended clinics that offered selective testing (defined as 5-85% of women tested per clinic-year) or incidental testing (<5% of women tested per clinic-year). We calculated the number of infections missed by selective testing by extrapolating prevalence for the routine universal testing group to that of weighted and unweighted samples of all selectively tested women. We used multivariable generalised estimating equations to identify independent risk factors for oropharyngeal N gonorrhoeae to identify the optimal selective testing strategy. FINDINGS: 554 266 consultations with at least one N gonorrhoeae test were recorded, of which 545 750 consultations (including repeat visits) were included in the analyses. Of 545 750 consultations, routine universal testing was used in 57 359 (10·5%), selective testing in 444 283 (81·4%), and incidental testing in 44 108 (8·1%). The prevalence of oropharyngeal N gonorrhoeae was 1·4% (95% CI 1·3-1·5; 703 of 50 962 consultations) in the routine testing group compared with 1·4% (1·3-1·5; 1858 of 132 276) in the selective testing group (p=0·68) and 2·8% (1·9-3·9; 30 of 1088) in the incidental testing group (p<0·0001). The prevalence of oropharyngeal-only infections was 47·7% (335 of 703 women) in the routine testing group, 53·3% (991 of 1858) in the selective testing group, and 60·0% (18 of 30) in the incidental testing group. Selective testing would have missed an estimated 4363 (70%; 95% CI 69-71) of all 6221 oropharyngeal N gonorrhoeae infections. Independent risk factors for oropharyngeal N gonorrhoeae were being notified for any STI (adjusted odds ratio 2·1, 95% CI 1·5-3·0), reporting sex work (4·0, 2·3-6·7), and having concurrent genital (51·5, 34·1-77·7) or anorectal (2·6, 1·4-4·8) N gonorrhoeae. Selective testing of women notified for any STI, or who reported sex work, would have led to 5418 (27·8%) of 19 455 women being tested and would have identified 119 (55·6%) of 214 oropharyngeal N gonorrhoeae infections. INTERPRETATION: Selective testing potentially misses more than two-thirds of oropharyngeal N gonorrhoeae infections in women, of whom half have oropharyngeal infections without concurrent genital or anorectal infections. Using independent risk factors for oropharyngeal infection to guide testing is a minimal testing strategy. Routine universal testing is the optimum scenario to detect the majority of infections. However, future studies are needed to assess the cost-effectiveness of routine testing and its effect on antimicrobial resistance. FUNDING: Public Health Service South Limburg.

Men and Women Have an Equal Oropharyngeal and Anorectal Chlamydia trachomatis Bacterial Load: A Comparison of 3 Anatomic Sites.

BACKGROUND: The Chlamydia trachomatis bacterial load could have impact on transmission and sequelae. This is the first study providing comparison of C. trachomatis load at 3 anatomic sites estimated by cycle quantification (Cq) values. METHODS: Data from 7900 C. trachomatis-positive samples were included (2012-2018). Cq value was used as an inversely proportional measure for C. trachomatis load. Multivariable linear regression analyses assessed differences in mean Cq values. RESULTS: Vaginal swabs had the lowest Cq values (31.0) followed by urine (32.5), anorectal swabs (34.0), and oropharyngeal swabs (36.8) (P < .001). Men and women had similar oropharyngeal (36.4 vs 37.3; P = .13) and anorectal (34.2 vs 33.9; P = .19) Cq values. Men (32.2) and women (30.7) aged <25 years had lower urogenital Cq values than men (32.8) and women (31.9) aged ≥25 years (P < .001). HIV-positive patients had higher urogenital Cq values than HIV-negative patients (33.8 vs 32.6; P < .03). CONCLUSIONS: Men and women have a similar C. trachomatis load at extragenital locations arguing for similar transmission potential and clinical relevance. Older patients and HIV-coinfected patients had lower C. trachomatis load, suggesting exposure to previous C. trachomatis infections potentially leading to partial immunity reducing load.

The characteristics of patients frequently tested and repeatedly infected with Chlamydia trachomatis in Southwest Limburg, the Netherlands.

BACKGROUND: Repeat Chlamydia trachomatis (CT) infections are common. To better understand the characteristics of patients frequently infected with CT at our sexually transmitted infection (STI) care services, we assessed the differences between patients repeatedly infected with CT and those who repeatedly tested negative. METHODS: In this cross-sectional analysis of cohort data, we assessed individuals tested for CT at different STI care providers between 2011 and mid-2018 in Southwest Limburg, the Netherlands (n = 17,616). Patients with ≥2 repeat CT infections in the study period were categorized as "patients with repeat CT infections." Multivariable logistic regression analyses were performed for the binary outcome measure: patients with repeat CT infections versus patients who repeatedly tested negative (reference group). Additional analyses were performed for only the STI clinic population. RESULTS: Patients aged < 25 years (OR: 1.83; 95%CI:1.38-2.43), co-infected with HIV (OR: 2.07; 95%CI: 1.02-4.22) or co-infected with Neisseria gonorrhoeae (NG) (OR: 5.04; 95%CI: 3.33-7.63) had more repeat CT infections. In additional analyses among exclusively STI clinic visitors, patients with urogenital symptoms (OR: 2.17; 95%CI: 1.41-3.35), and patients notified for STIs (OR: 4.55; 95%CI: 3.17-6.54) had more frequent repeat CT infections. CONCLUSIONS: Patients aged < 25 years and patients coinfected with HIV or NG had more frequent repeat CT infections, accounting for ~ 20% of the diagnosed CT infections. These patients are likely at the highest risk for transmitting and acquiring CT. Therefore, testing and retesting this group remains important to enhance CT control.

Attitude and beliefs about the social environment associated with chemsex among MSM visiting STI clinics in the Netherlands: An observational study.

BACKGROUND: Drug use during sex, 'chemsex', is common among men who have sex with men (MSM) and related to sexual and mental health harms. This study assessed associations between chemsex and a wide range of determinants among MSM visiting STI clinics to increase understanding of characteristics and beliefs of MSM practicing chemsex. METHODS: In 2018, 785 MSM were recruited at nine Dutch STI clinics; 368 (47%) fully completed the online questionnaire. All participants reported to have had sex in the past six months. Chemsex was defined as using cocaine, crystal meth, designer drugs, GHB/GBL, ketamine, speed or XTC/MDMA during sex in the past six months. Associations between chemsex and psychosocial determinants, socio-demographics, sexual behaviour and using tobacco or alcohol were assessed by multivariable logistic regression analyses. RESULTS: Chemsex was reported by 44% of MSM (161/368) and was not associated with socio-demographics. Independent determinants were 'believing that the majority of friends/sex partners use drugs during sex' (descriptive norm) (aOR: 1.95, 95%CI: 1.43-2.65), 'believing that sex is more fun when using drugs' (attitude) (aOR: 2.06, 95%CI: 1.50-2.84), using tobacco (aOR: 2.65, 95%CI: 1.32-5.32), multiple sex partners (aOR: 2.69, 95%CI: 1.21-6.00), group sex (aOR: 4.65, 95%CI: 1.54-14.05) and using online dating platforms (aOR: 2.73, 95%CI: 1.13-6.62). CONCLUSION: MSM are likely to find themselves in distinct social networks where it is the norm to use drugs when having sex and pleasure is linked to chemsex. Health services should acknowledge the social influence and pleasurable experiences to increase acceptability of strategies aimed at minimizing the possible harms of chemsex.

Men and Women Repeatedly Infected With Chlamydia trachomatis Have a Lower Urogenital Bacterial Load.

We assessed whether patients repeatedly infected with Chlamydia trachomatis (CT) have a lower urogenital or anorectal CT load. A CT-positive retest was independently associated with higher vaginal and higher urine Cq values (P<0.01). Partial immunity could play a role in repeat urogenital infections, potentially not in anorectal infections.

The Availability and Feasibility of Chemsex Services Within Sexually Transmitted Disease Clinics in the Netherlands: A Cross-Sectional Survey Among Sexually Transmitted Disease Nurses.

OBJECTIVES: Chemsex-using illicit drugs during sex-is prevalent among men who have sex with men (MSM) and associated with sexual and mental health harms. Sexually transmitted disease (STD) clinics are a frequently visited and trusted health care facility for MSM. This study assessed the frequency and extent to which chemsex is addressed by Dutch STD nurses. METHODS: Of the 24 Dutch public STD clinics, an online questionnaire was distributed in 20 STD clinics (83%) in 2019; the questionnaire was sent to 191 STD nurses, of whom 108 (57%) completed the questionnaire. The main outcome was addressing chemsex during regular MSM consultations, measured on a 5-point Likert scale (never-always). Items measuring knowledge, attitude, self-efficacy, and the social norm were also measured on a 5-point Likert scale (totally disagree-totally agree). RESULTS: Of the 108 participating STD nurses, 77 (71%) addressed chemsex regularly or always during MSM consultations. In general, STD nurses indicated to have sufficient knowledge about chemsex (mean [SD], 3.6 [0.5]) and a positive attitude toward addressing chemsex (mean [SD], 4.3 [0.5]). A need for training on chemsex was reported by 82 (76%) STD nurses, especially in signaling problematic chemsex (56/82; 68%). Three STD clinics (15%) had a protocol on addressing chemsex, and 3 STD clinics (15%) had referral pathways to addiction care. CONCLUSION: Sexually transmitted disease nurses from Dutch STD clinics regularly addressed chemsex during MSM consultations. Our results show relevance of educating STD nurses on signaling problematic chemsex and arranging referral pathways to addiction care to optimize chemsex related health care.

Sex Abroad Among Men Who Have Sex With Men and Its Association With Chemsex, Sexual Risk Behavior, and Sexually Transmitted Diseases: A Cross-Sectional Study in the Netherlands.

Almost half of men who have sex with men visiting Dutch sexually transmitted disease clinics reported sex abroad in the past 6 months, mainly in Western countries. One in 4 men who have sex with men who had sex abroad used drugs during sex ("chemsex") abroad. Having sex abroad was associated with having multiple sex partners and casual sex partner(s).

What Is the Optimal Testing Strategy for Oropharyngeal Neisseria gonorrhoeae in Men Who Have Sex With Men? Comparing Selective Testing Versus Routine Universal Testing From Dutch Sexually Transmitted Infection Clinic Data (2008-2017).

BACKGROUND: Most oropharyngeal Neisseria gonorrhoeae infections are asymptomatic, and many infections remain undetected, creating a reservoir for ongoing transmission and potential drug resistance. It is unclear what the optimal testing policy is in men who have sex with men (MSM), as routine universal testing data are lacking. METHODS: Surveillance data from all Dutch sexually transmitted infection (STI) clinics between 2008 and 2017 were used (N = 271 242 consultations). Oropharyngeal testing policy was defined as routine universal testing when ≥85% of consultations included oropharyngeal testing or as selective testing (<85% tested). Independent risk factors for oropharyngeal N. gonorrhoeae were assessed among MSM routinely universally screened using backward multivariable logistic regression analyses. RESULTS: Routine universal testing was performed in 90% (238 619/265 127) of consultations. Prevalence was higher using routine universal testing (5.5%; 95% CI, 5.4-5.6; 12 769/233 476) than with selective testing (4.7%; 95% CI, 4.4-5.0; 799/17 079; P < .001). Proportions of oropharyngeal-only infections were 55% and 47%, respectively. Independent risk factors were age <31 years (OR, 2.1; 95% CI, 1.9-2.3), age 31-43 years (OR, 1.7; 95% CI, 1.6-1.9, compared with >43 years), being notified for any STI (OR, 2.0; 95% CI, 1.9-2.1), concurrent urogenital N. gonorrhoeae (OR, 2.4; 95% CI, 2.1-2.7), and concurrent anorectal N. gonorrhoeae (OR, 11.4; 95% CI, 10.6-12.3). When using any of the risk factors age, notified, or oral sex as testing indicators, 98.4% (81 022/82 332) of MSM would be tested, finding 99.5% (4814/4838) of infections. CONCLUSIONS: Routine universal testing detected more oropharyngeal N. gonorrhoeae infections than selective testing, of which more than half would be oropharyngeal only. Using independent risk factors as testing indicator is not specific. Therefore, routine universal oropharyngeal testing in MSM is feasible and warranted, as currently advised in most guidelines.

Prevalence of drug use during sex among swingers and perceived benefits and risks - a cross-sectional internet survey in the Netherlands.

OBJECTIVES: Drug use during sex has been associated with sexually transmitted infections (STI). While a growing body of research has investigated drug use during sex among men who have sex with men, data in swingers is limited. Swingers are heterosexual couples who have sex with others and singles who have sex with these couples. Our study assessed the prevalence of drug use during sex and perceived benefits and risks among swingers. METHODS: In 2018, 1005 swingers completed an online questionnaire that was advertised at Dutch swinger-websites. We assessed the associations between drug use during sex <6 months (any drug use excluding alcohol and erection medicines) and sociodemographic characteristics, alcohol use and condomless sex using backward multivariable logistic regression analysis. We compared drug use, motives, beliefs and experienced effects between heterosexual male, bisexual male and female drug-using swingers using χ2-tests. RESULTS: Drug use during sex was reported by 44% (443/1005): 51% in women, 44% in bisexual men and 39% in heterosexual men (P<0.01). Condomless vaginal (46%) and anal sex (22%) was higher in drug-using swingers (vs 34% and 13% in non-drug-using swingers, P<0.001). Among drug-using swingers, XTC (92%), GHB (76%) and laughing gas (69%) were mostly used. Prolonging sex (68%) and increasing arousal (66%) were the most reported motives. Most reported positive effects were feeling happy (78%) and increasing energy (78%). Ninety-four per cent considered drug use to be pleasurable. The most reported negative effect was feeling tired (53%), 7% reported that they might become addicted or felt uncomfortable having sex without drugs. CONCLUSION: This study among a large group of swingers shows that drug use during sex is highly prevalent. STI clinics should discuss drug use during sex among swingers and provide information on safer sex and drug use, while acknowledging the perceived benefits, such as the increased quality of sex.

High Rate of Repeat Sexually Transmitted Diseases Among Men Who Have Sex With Men in South Africa: A Prospective Cohort Study.

We observed a high rate of incident sexually transmitted diseases within 55 days (median) of follow-up (78% retention) among symptomatic men who have sex with men (n = 78) in South Africa (188 per 100 person-years; 95% confidence interval, 1.2-2.7); 16 newly acquired and 10 with persistent positivity. This highlights the need to strengthen prevention efforts, whereas introduction of diagnostics is urgently warranted.

Chemsex among men who have sex with men living outside major cities and associations with sexually transmitted infections: A cross-sectional study in the Netherlands.

BACKGROUND: The intentional use of drugs to have sex-chemsex-among men who have sex with men (MSM) might contribute to the high sexually transmitted infections (STI) prevalence in this group. Limited data is available on chemsex outside major cities. The current study investigated the use of a wide variety of drugs during sex among MSM living outside major cities in the Netherlands and their associations with STI. METHODS: In 2018, 350 MSM were recruited at STI clinics and 250 MSM completed an online questionnaire. Questionnaire data were linked to clients' most recent STI laboratory test results. Chemsex was defined as using cocaine, crystal meth, designer drugs, GHB/GBL, ketamine, speed, or XTC/MDMA during sex in the preceding six months. The use of other drugs was also assessed. Determinants (chemsex, specific drugs, number of drugs, combining, and frequency) potentially associated with STI were assessed using multivariable logistic regression analyses adjusting for sociodemographic characteristics and sexual history. RESULTS: Chemsex was reported by 35% (95%CI: 29-41) of the 250 participants. XTC/MDMA (27%; 68/250) and GHB/GBL (26%; 64/250) were the most used drugs. STI positivity was 33% (29/87) in MSM engaging in chemsex and 12% (12/163) in MSM not engaging in chemsex (p<0.001). Half of MSM engaging in chemsex (45/87) used three of more different chemsex drugs; STI positivity in this group was 44% (20/45). The only factor independently associated with STI was the use of three or more chemsex drugs (aOR: 4.13, 95%CI: 1.77-9.62). CONCLUSION: This study shows that chemsex is prevalent among MSM visiting the STI clinic outside major cities in the Netherlands, suggesting that health services in both urban and non-urban areas should be aware of and informed on chemsex. MSM who used multiple drugs are at particular risk for STI, indicating a special need for STI prevention and care in this group.

Genital and anal Chlamydia trachomatis bacterial load in concurrently infected women: a cross-sectional study.

OBJECTIVES: Most international STI guidelines recommend Chlamydia trachomatis anorectal testing in women after self-reported sexual exposure or symptoms in women. However, it has been shown that the prevalence of anorectal C. trachomatis is as high (7%-17 %) in women who do not report anorectal intercourse (AI) as in women who do. This study assessed the correlation between the genital and anorectal C. trachomatis load in concurrently infected women for increased microbiological insight. METHODS: A convenience sample of 105 women with a concurrent (genital and anorectal) C. trachomatis infection was included from the STI clinic in South Limburg, the Netherlands. Women provided self-collected vaginal and anorectal swabs. The C. trachomatis load was quantified with qPCR and the human cell load was assessed to ensure sample adequacy. Genital and anorectal C. trachomatis loads were divided into tertiles for comparison. The χ2 test and linear regression were used to compare genital and anorectal C. trachomatis loads and identify determinants associated with load. RESULTS: The overall median C. trachomatis load was higher in genital (median 5.3 log10C. trachomatis/ml) than anorectal samples (median 3.4, p ≤ 0.001), but both loads were within the same range. The genital and anal load categories were not related within one woman (p = 0.99), both in women with and without AI. The anorectal C. trachomatis load was in the same or higher load category than the genital load in 56% of women without AI, and 79% of women with AI. CONCLUSIONS: Although no cut-off for clinical relevance is known, an anorectal C. trachomatis load in the same or higher load category than the genital C. trachomatis load is likely to be clinically relevant. Other measurements should also be taken into account, such as leucocytes or bacterial viability to distinguish infection from contamination or exposure.

Chlamydia trachomatis bacterial load, estimated by Cq values, in urogenital samples from men and women visiting the general practice, hospital or STI clinic.

BACKGROUND: The bacterial load of Chlamydia trachomatis (CT) is assumed to play a role in transmission and sequelae. We assessed urogenital CT cycle quantification (Cq) values, as an indicator for CT load, of men and women diagnosed by general practitioners (GPs), hospital physicians and the STI clinic. METHODS: Urogenital CT-positive samples (n = 2,055 vaginal swabs, n = 77 cervical swabs, n = 1,519 urine samples and n = 19 urethral swabs) diagnosed by GPs, hospital physicians and the STI clinic from the Maastricht Medical Microbiology Laboratory were included (2012-2016). The outcome measure 'urogenital Cq values' was used as an inversely proportional measure for CT load. Among all patients, multivariate linear regression analyses were used to assess primary determinants for mean urogenital Cq values, stratified by sex. Additional clinical determinants were assessed among STI clinic patients. RESULTS: In men, mean urogenital Cq values were similar between GPs, hospital physicians and the STI clinic (32.7 and 33.5 vs. 32.7; p>0.05). Women visiting the GP had lower urogenital Cq values than women visiting the STI clinic (30.2 vs. 30.9; p = <0.001). Women visiting the hospital had higher urogenital Cq values than women visiting the STI clinic (32.4 vs. 30.9; p = <0.001). Among STI clinic women, urogenital Cq values were lower in women with concurrent anorectal CT and in rectally untested women compared to anorectal CT-negative women (30.7 and 30.6 vs. 33.9; p = <0.001). CONCLUSION: Men visiting different STI care providers had similar urogenital Cq values, which could be an indicator for similar CT loads. The lower Cq values of women visiting the GP compared to women visiting the STI clinic could be an indicator for higher CT loads and likely higher transmission potential. Notably, urogenital Cq values of STI clinic women were much lower (>3 Cq) when STI clinic women also had anorectal CT. This finding could indicate higher urogenital CT loads and likely higher chances of transmission and sequelae.

Spontaneous clearance of urogenital, anorectal and oropharyngeal Chlamydia trachomatis and Neisseria gonorrhoeae in women, MSM and heterosexual men visiting the STI clinic: a prospective cohort study.

OBJECTIVE: Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections can clear without treatment. Despite high prevalence of anorectal infections in men who have sex with men (MSM) and women, studies on anorectal clearance are scarce. Moreover it is unknown whether bacterial load affects urogenital/anorectal CT clearance. In this prospective cohort study, CT and NG clearance is assessed at three anatomical sites of men and women. METHODS: CT-positive and NG-positive MSM, heterosexual men and women ≥18 years of age visiting our STI clinic between 2011 and 2013 underwent a repeat test when returning for treatment (n=482). The primary outcome was clearance, defined as a positive nucleic acid amplification test (NAAT) at screening-consultation, followed by a negative NAAT at treatment-consultation. Sociodemographics, sexual risk behaviour and CT bacterial load (inhouse quantitative PCR) were tested as determinants for clearance using multivariable logistic regression for CT and Fisher's exact test for NG. RESULTS: CT clearance was 9.1% (10/110) for urine, 6.8% (20/292) for vaginal swabs, 12.7% (8/63) for anorectal swabs (ie, 4.0% [1/25] in MSM and 18.4% [7/38] in women) and 57.1% (4/7) for oropharyngeal swabs. For NG this was 33.3% (2/6), 28.6% (2/7), 20.0% (2/10) and 27.3% (6/22), respectively. The number of days between tests (median 10, IQR 7-14) was not associated with clearance. Lower bacterial load at screening was the only predictor for CT clearance (urine mean 1.2 vs 2.6 log CT/mL, p=0.001; vaginal swabs mean 2.1 vs 5.2 log CT/mL p<0.0001; anorectal swabs mean 2.0 vs 3.7 log CT/mL, p=0.002). None of the tested determinants were associated with NG clearance. CONCLUSIONS: This study reports the largest number of anorectal infections tested for CT and NG clearance to date. Clearance in all sample types was substantial: between 7% and 57% for CT, and between 20% and 33% for NG (notwithstanding low absolute numbers). CT clearance was associated with a lower load at screening. However, not all individuals with low bacterial CT load cleared the infection, hampering STI guideline change.