M S van Rooijen

Comparison of two Gram stain point-of-care systems for urogenital gonorrhoea among high-risk patients: diagnostic accuracy and cost-effectiveness before and after changing the screening algorithm at an STI clinic in Amsterdam

Objectives To compare point-of-care (POC) systems in two different periods: (1) before 2010 when all high-risk patients were offered POC management for urogenital gonorrhoea by Gram stain examination; and (2) after 2010 when only those with symptoms were offered Gram stain examination. Methods Retrospective comparison of a Gram stain POC system to all high-risk patients (2008–2009) with only those with urogenital symptoms (2010–2011) on diagnostic accuracy, loss to follow-up, presumptively and correctly treated infections and diagnostic costs. Culture was the reference diagnostic method. Results In men the sensitivity of the Gram stain was 95.9% (95% CI 93.1% to 97.8%) in 2008–2009 and 95.4% (95% CI 93.7% to 96.8%) in 2010–2011, and in women the sensitivity was 32.0% (95% CI 19.5% to 46.7%) and 23.1% (95% CI 16.1% to 31.3%), respectively. In both periods the overall specificity was high (99.9% (95% CI 99.8% to 100%) and 99.8% (95% CI 99.7% to 99.9%), respectively). The positive predictive value (PPV) and negative predictive value (NPV) before and after 2010 were also high: PPV 97.0% (95% CI 94.5% to 98.5%) and 97.7% (95% CI 96.3% to 98.6%), respectively; NPV 99.6% (95% CI 99.4% to 99.7%) and 98.8% (95% CI 98.5% to 99.0%), respectively. There were no differences between the two time periods in loss to follow-up (7.1% vs 7.0%). Offering Gram stains only to symptomatic high-risk patients as opposed to all high-risk patients saved €2.34 per correctly managed consultation (a reduction of 7.7%). Conclusions The sensitivity of the Gram stain is high in men but low in women. When offered only to high-risk patients with urogenital symptoms, the cost per correctly managed consultation is reduced by 7.7% without a significant difference in accuracy and loss to follow-up.

Trichomonas vaginalis and Mycoplasma genitalium: age-specific prevalence and disease burden in men attending a sexually transmitted infections clinic in Amsterdam, the Netherlands

Background Men are not routinely tested for Trichomonas vaginalis (TV) and Mycoplasma genitalium (MG) in the Netherlands and, therefore, very few studies have looked into their prevalence and/or role in urogenital complaints in the Dutch male population. Objective To describe the age-specific prevalence and disease burden of TV and MG, and their co-occurrence with Chlamydia trachomatis (CT), in men attending the sexually transmitted infections (STI) clinic in Amsterdam, the Netherlands. Methods Urine samples and clinical data were collected from 526 men who have sex with women (MSW) and 678 men who have sex with men (MSM) attending the STI clinic. To investigate age as a risk factor, we oversampled older men. Urine samples were tested for TV and MG using molecular tests. Results The overall prevalence was 0.5% (6/1204) for TV and 3.1% (37/1204) for MG. Four out of the six TV cases were older than 40 years and all TV cases were MSW. No age trend was observed for MG, nor did MG prevalence differ between MSW and MSM. Co-infections between TV or MG and CT were rare. TV infection did not associate with urogenital symptoms, whereas 5.9% of men reporting urogenital symptoms were infected with MG. Conclusions TV infection was rare in men, asymptomatic and was limited to the heterosexual network. MG infection was relatively common and equally prevalent among MSW and MSM of all ages. Most MG infections remained asymptomatic, however, our results suggest that up to 6% of urogenital complaints could be explained by MG infection.

Is rectal douching and sharing douching equipment associated with anorectal chlamydia and gonorrhoea? A cross-sectional study among men who have sex with men

Introduction Men who have sex with men (MSM) are at high risk for anorectal chlamydia and gonorrhoea infections. Many MSM use rectal douches in preparation for sex, which might break down the mucosal barrier function and facilitate the acquisition of STI. We determined whether rectal douching or sharing douching equipment was associated with anorectal chlamydia and gonorrhoea. Methods In a cross-sectional study among 994 MSM attending the STI outpatient clinic of Amsterdam between February and April 2011, data were collected on rectal douching, sexual behaviour and STI. We used multivariable logistic regression analysis to determine the association between rectal douching, including sharing of douching equipment, and anorectal chlamydia and gonorrhoea for those reporting receptive anal sex. We adjusted for other risk behaviour, that is, condom use, number of partners and HIV status. Results Of 994 MSM, 46% (n=460) practised rectal douching, of whom 25% (n=117) shared douching equipment. Median age was 39 years (IQR 30–47), median number of sex partners in the 6 months prior to consult was five (IQR 3–10) and 289 (29.0%) participants were HIV positive. The prevalence of anorectal chlamydia and/or gonorrhoea for those reporting receptive anal sex was 9.6% (n=96). In multivariable analysis, HIV positivity (aOR=2.2, 95% CI 1.3 to 3.6), younger age (aOR=2.5, CI 1.4 to 4.5 for those aged <35 years compared with those aged ≥45 years), and more sexual partners (aOR=1.2, 95% CI 1.0 to 1.5 for 1 log increase) were significantly associated with anorectal STI. However, rectal douching or sharing douching equipment were not significantly associated with anorectal chlamydia and/or gonorrhoea (p=0.647). Conclusions Almost half of MSM used rectal douching and a quarter of these shared douching equipment. Though using douching equipment does not appear to contribute to anorectal chlamydia and gonorrhoea in this study, STI prevalence remains high and prevention strategies like early testing and treatment remain of utmost importance.

Point-of-care management of urogenital Chlamydia trachomatis via Gram-stained smear analysis in male high-risk patients. Diagnostic accuracy and cost-effectiveness before and after changing the screening indication at the STI Clinic in Amsterdam

Objectives To measure the effect of changing the point-of-care (POC) testing algorithm of urogenital chlamydia for all male high-risk patients to those with only symptoms with respect to: diagnostic accuracy, loss to follow-up, correctly managed consultations and costs. Methods Retrospective comparison of the diagnostic accuracy and cost-effectiveness of Gram-stained urethral smear analysis for the POC management of urogenital Chlamydia trachomatis infections. Between 2008 and 2009 Gram-stained urethral smear analysis was offered to all men irrespective of symptoms; between 2010 and 2011 only to those with symptoms. The Aptima CT assay was the reference diagnostic test. Results The number of examined Gram-stained smears in the two periods was respectively 7185 (2008–2009 period) and 18 852 (2010–2011 period). The sensitivity of the Gram stain analysis was respectively 83.8% (95% CI 81.2% to 86.1%) and 91.0% (95% CI 89.5% to 92.3%) (p<0.001). The specificity was respectively 74.1% (95% CI 73.0% to 75.2%) and 53.1% (95% CI 51.8% to 54.4%) (p<0.001). The positive predictive value was low in both periods, respectively 31.7% (95% CI 29.8% to 33.6%) and 35.6% (95% CI 34.1% to 37.1%) (p=0.002), whereas the negative predictive value was high, respectively 97.0% (95% CI 96.4% to 97.4%) and 95.4% (95% CI 94.6% to 96.1%) (p=0.002). The loss to follow-up rate between 2008–2009 and 2010–2011 was, respectively, 1.8% (95% CI 1.0% to 2.9%) vs 2.3% (95% CI 1.7% to 3.0%) (p=0.36). There was a small difference in overtreatment, 68.0% (95% CI 66.0% to 69.8%) vs 64.1% (95% CI 62.6% to 65.5%) (p=0.001). The cost per correctly managed consultation was 14.3% lower in the 2010–2011 period (€94.31 vs €80.82). The percentage of delayed treated infections was significantly lower in the 2008–2009 period (10.5%) compared with the 2010–2011 period (22.8%) (p<0.001). Conclusions With a high sensitivity in male high-risk patients, the Gram-stained urethral smear is a useful POC test to detect urogenital C. trachomatis. When offered only to men with urogenital symptoms the specificity decreases but the cost per correctly managed consultation is reduced with 14.3% without a significant difference in loss to follow-up but with a significantly higher rate of delayed treatment.

P5.022 Earlier HCV Diagnosis by the Introduction of Routine HCV Testing For HIV Positive MSM and MSM Opting Out For HIV in a Large STI Outpatient Clinic

Background In October 2007 at a large STI outpatient clinic (SOC), anti-HCV screening was introduced for HIV unaware MSM opting-out for HIV testing (MOH) and HIV-positive MSM. We evaluated whether this screening resulted in additional and earlier HCV diagnosis in HIV-positive MSM also attending HIV treatment centres (HTC). Methods At first visit, MOH and HIV-positive MSM visiting the SOC in Amsterdam were screened for anti-HCV. During follow-up visits, only those previously HCV negative were tested. Retrospectively, date of new HCV diagnosis at SOC was compared with HCV data provided by HTC. Results The anti-HCV prevalence at first screening was 0.7% (3/450) among MOH and 6.4% (112/1,742) among HIV-positive MSM of whom 30% (34/112) did not report a history of HCV. In 133 follow-up visits to MOH 0 and in 3,286 follow-up visits to HIV-positive MSM 52 HCV seroconversions were found. These 52 seroconverters and the 34 MSM anti-HCV positive at first screening, excluding 13 MSM who were detected at HTC before SOC started anti-HCV screening, were compared with HTC data. Additional data from HTC was available for 56/73 clients. 29/56 (52%) were first diagnosed at SOC: 7 were concurrently diagnosed with HIV and not in care at HTC; 11 were scheduled for a routine visit at HTC within 1 month; 3 within 3 months; 3 within a year and all 17 were tested and diagnosed with HCV at HTC because of elevated ALT values; 3 HCV diagnoses would have been missed because ALT was low or considered non-HCV related; 2 missed ALT data. Conclusions The introduction of routine HCV-antibody screening in SOC resulted in additional and earlier diagnoses of HCV in MSM. Testing should focus on HIV-positive MSM especially those newly diagnosed with HIV. Since anti-HCV testing does not identify acute infections, additional testing policies should be evaluated at SOC.

P3.271 Identical Multilocus Sequence Typing (MLST) Analysis in Sequential Samples from Patients with Pharyngeal Chlamydia Infections

Introduction Pharyngeal Chlamydia trachomatis (PCt) must persist to contribute to ongoing transmission. In a retrospective study, we examined MLST-types of PCt in patients who had a positive pharyngeal swab on two visits, and had not been treated for this infection at first visit. Methods From 1/1/2008 to 14/7/2010, pharyngeal swabs from patients at risk for pharyngeal gonorrhoea were tested with the AC2 (Hologic-GenProbe) test. Since at that time PCt detection was not considered to represent an infection, PCt results were not reported and patients were not treated, unless they had a chlamydial infection at another anatomic site. We looked for patients who had a positive PCt test on two different occasions with an interval of at least 3 weeks. For inclusion in the study, patients were required to have no Chlamydia infections at other anatomic locations at first visit and therefore received no treatment. PCt typing was done by MLST on stored specimens. Results Sixteen patients could be included and paired pharyngeal samples from four of those patients contained enough DNA for MLST analysis. The intervals between the two visits were 112, 168, 207 and 268 days, respectively. In all four patients MLST types of both pharyngeal samples were completely identical. Patients were two women and two men who had sex with men (MSM). At second visit one woman and one MSM reported commercial sex work and had 30 and 150 sexual partners in the last 6 months, respectively. The second woman reported sex with two known persons and the second MSM reported sex with 15 known persons. None reported sex with a steady partner. Conclusion Our findings of identical MLST types are consistent with persistent PCt infection for a period of 3–9 months, although repetitive exposure to untreated partners with identical C. trachomatis strains can not be excluded.

P3.139 Early Incubating Gonorrhoea and Chlamydia Infections in MSM with an Indication For HIV Post Exposure Prophylaxis (PEP)

Introduction A PEP indication is an ideal opportunity for safe sex promotion and STI screening. Since 2010 the STI outpatient clinic in Amsterdam, the Netherlands, offers PEP to HIV negative men who have sex with men (MSM) who had unprotected receptive anal intercourse within the last 72 hours. If STI screening is performed at the moment of PEP request, early incubating chlamydia and gonorrhoea infections acquired during the unsafe sex act, are possibly missed. We aimed to determine if chlamydia and gonorrhoea screening should be repeated in MSM 2 weeks after a PEP indication. Methods We included all MSM visiting the STI clinic with a PEP request in the period from April 2010 until December 2012. STI testing was offered to all MSM during the PEP evaluation visit. Men were screened for urethral, anal and pharyngeal infections based on their practised sex techniques. If PEP was indicated a visit was planned 2 weeks later to repeat gonorrhoea, and chlamydia screening. Results 447 consultations MSM requested PEP and in 325 (72.7%) PEP was indicated. In 50/325 (15%) cases at least one STI was diagnosed at the moment of PEP indication. 172 (52.9%) cases returned after 2 weeks of whom in 9 (5.2%) cases at least one previously undiagnosed infection was found (3 rectal chlamydia, 3 rectal gonorrhoea, 2 rectal chlamydia/gonorrhoea double infections, and 1 pharyngeal chlamydia). Conclusion Repeated chlamydia and gonorrhoea screening 2 weeks after a PEP indication in MSM revealed 5.2% additional, possibly early incubating, infections. Yet, 47.1% of MSM did not show up for the second screenings visit. Therefore STI screening should be offered at the PEP indication visit and preferably repeated after 2 weeks to exclude early incubating chlamydia and gonorrhoea infections.

P5.014 What is the Optimal Time to Rescreen STI Clinic Visitors with a Urogenital Chlamydia Infection

Background and Aim STI clinic visitors with a urogenital chlamydia infection (Ct) have a high re-infection rate. Retesting can be an effective strategy to prevent onward transmission and late sequelae. The optimal moment to offer a re-test is unknown. Methods Between May 2012 and January 2013, all heterosexual visitors of the Amsterdam STI clinic, testing positive for urogenital Ct were offered retesting after receiving diagnosis, treatment and counselling. Participants were randomly assigned for re-testing after 2, 4 or 6 months. Participants were free to choose between two retest options; receive a home collection kit or an email/SMS invitation to return to the clinic for a self collected retest. Results In total 1784 individuals were included of whom 47% were male, 74% were Dutch and the median age was 23 years (IQR 20–26). 779 (44%) opted for the home collection kit and 1005 (56%) for re-visiting the clinic. At this point, 795 are eligible to evaluate retesting; 265 home collection kits were returned (75%) and 237 individuals returned to the clinic for a retest (54%). Overall, the participation rate did not differ between the assigned time periods. A test result was available for 266, 126 and 49 individuals in the 2, 4 and 6 month group, respectively. The overall positivity rate at 2, 4 and 6 months was respectively 8%, 6% and 12%. Conclusions Based on these preliminary data we found a high test uptake. Possibly because individuals were able to choose their preferred method of retesting. As the participation rate was not affected by the period of the retest and the positivity rate seemed to be highest after 6 months this might be an optimal time interval to offer a retest to STI clinic visitors. We conclude that retesting is feasible in identifying new Ct infections.

P3.167 Young Commercial Sex Workers Are at Higher Risk of Sexually Transmitted Infections, the Netherlands, 2006–2011

Background Commercial sex workers (CSW) are particularly exposed to sexually transmitted infections (STI). To direct prevention measures, we estimated the prevalence of the three most common bacterial STI (chlamydia, gonorrhoea and syphilis) and examined factors associated with infection among CSW visiting an STI-clinic in the Netherlands. Methods A CSW was defined as a person exchanging sex for money or other valuable goods in the past 6 months prior to the consultation. Using 2006–2011 national surveillance data on STI clinic visits, we estimated the prevalence of consultations with at least one STI (positive laboratory test for chlamydia, gonorrhoea and/or syphilis). We used univariable and multivariable logistic regression to identify factors associated with these STI, stratified by gender. Results Between 2006 and 2011, the prevalence of bacterial STI was 9% among 23,825 female sex workers (FSW) and 18% among 2,353 male sex workers (MSW) consultations. Young CSW (15–24 years) had a higher prevalence (27% for MSW, 16% for FSW) than CSW aged > = 25 years (15% for MSW, 7% for FSW, p < 0.0001). Prevalence of STI was higher among MSW having sex with men than among heterosexual MSW (OR = 1.9 95% CI: 1.4–2.5). MSW who already knew their HIV positive status and MSW who were diagnosed as HIV positive during the consultation had a higher prevalence than those who were tested negative for HIV (OR = 4.8 95% CI: 2.8–8.2 and OR = 3.4 95% CI: 2.3–4.9 respectively). Conclusions Young male and female CSW, MSW having sex with men and known HIV-positive MSW had a higher prevalence of STI. Prevention activities need to target young sex workers to increase early diagnosis, prevention and treatment. MSW having sex with men and those known HIV positive may require more targeted interventions.

O1-S03.05 Community-acquired methicillin-resistant and susceptible Staphylococcus aureus among men who have sex with men

Background Community Acquired Methicillin Resistant Staphylococcus aureus (CA-MRSA) has been found more often among men who have sex with men (MSM) in some studies (USA). This study assesses the prevalence and sexual risk factors for CA-MRSA and methicillin susceptible Staphylococcus aureus (MSSA) colonisation and infection among MSM in Amsterdam, the Netherlands. Methods MSM attending the sexually transmitted infections outpatient clinic in Amsterdam were invited to participate in this study and divided in two groups: (1) MSM with clinical signs of a skin/soft tissue infection (symptomatic group) and (2) MSM without clinical signs of such infections (asymptomatic group). Demographic characteristics, medical history, sexual behaviour, history of sexual contacts and known risk factors for colonisation with S aureus were collected through a self-completed questionnaire. Swabs were collected from the anterior nasal cavity, throat, perineum, penile glans and, if present, from infected skin lesions. Culture for S aureus was done on blood agar plates and for MRSA broth on selective chromagar plates after enrichment in broth. If MRSA was found, the sex partners of the index patient were invited for screening for MRSA. Results Between October 2008 and April 2010 a total of 214 MSM were included in the study: 76 into the symptomatic group and 138 MSM into the asymptomatic group. The prevalence of MSSA in the nose was 36% (78/214) and in skin lesions 36% (27/76). The prevalence of MRSA was 0.9% (2/214). Both MRSA cases, one asymptomatic and one symptomatic, were HIV positive. The asymptomatic MRSA carrier had been hospitalised the previous year. None of the four sexual contacts that could be traced were colonised by MRSA. The symptomatic MRSA case had a soft tissue infection in the genital area; in this case also the nasal cavity, perineum and glans penis were positive for MRSA. No sexual contacts could be traced. There were no significant differences in age, sexual risk behaviour, drug use, history or diagnoses of sexual transmitted diseases, circumcision status or hygiene behaviour between those with and without a genital S aureus infection, but those infected with S aureus were significantly more often HIV infected (55% vs 34%; p<0.01). Conclusion CA-MRSA among MSM STI outpatient clinic visitors in Amsterdam is rare. There were no indications for sexual transmission of MRSA or MSSA in this population.