Mycoplasma genitalium in men who have sex with men at male-only saunas.

OBJECTIVES: To determine the prevalence and clinical associations of Mycoplasma genitalium in urethral, rectal and pharyngeal specimens collected from men who have sex with men (MSM) attending male-only saunas. METHODS: A cross-sectional study of 521 MSM attending six male-only saunas in Melbourne was conducted between October 2001 and September 2002. Stored urine and rectal and pharyngeal swabs were tested for M genitalium by real-time polymerase chain reaction. The prevalence of M genitalium and clinical associations were determined. RESULTS: A high prevalence (12.9%; 95% CI 10.2% to 15.9%) of sexually transmitted infections (STIs) was found in MSM. M genitalium (2.1%; 95% CI 1.1% to 3.6%) was less common than Chlamydia trachomatis (8.1%; 95% CI 5.9% to 10.6%, p<0.001), and Neisseria gonorrhoeae (4.8%; 95% CI 3.2% to 6.9%, p = 0.02). M genitalium was most likely to be detected as an asymptomatic rectal (1.6%; 95% CI 0.8% to 3.0%) or urethral infection (0.6%; 95% CI 0.2% to 1.6%, p = 0.12), but was absent from the pharynx. In comparison, C trachomatis was more common in the rectum (6.2%; 95% CI 4.3% to 8.6%) than urethra (1.8%; 95% CI 0.9% to 3.2%, p = 0.004), and was uncommon in the pharynx (0.6%; 95% CI 0.1% to 1.6%). Urethral infection with N gonorrhoeae (0.2%; 95% CI 0.01% to 1.0%) was rare, but it was as common in the pharynx (2.5%; 95% CI 1.4% to 4.2%) as the rectum (2.2%; 95% CI 1.2% to 3.8%). No significant demographic or behavioural associations with M genitalium were identified. CONCLUSION: M genitalium was less common than C trachomatis and N gonorrhoeae in MSM attending male-only saunas and was most often detected as an asymptomatic rectal or a urethral infection but was absent from the pharynx. To inform STI screening strategies in MSM, more data are needed to understand how common M genitalium infection is in urethral and non-urethral sites in MSM, and how it contributes to clinical symptoms.

Evaluation of PorB variable region typing of Neisseria gonorrhoeae using PCR-ELISA in samples collected from men who have sex with men.

A polymerase chain reaction (PCR)-based enzyme-linked immunosorbent assay (ELISA) methodology was developed to characterize Neisseria gonorrhoeae porB gene variable regions (VR); the methodology was evaluated in comparison to porB VR typing by checkerboard hybridization. Clinical noncultured samples from 35 men who have sex with men (MSM), positive by nucleic amplification assays for N. gonorrhoeae, were typed using a panel of 40 oligonucleotide probes to porB VRs and compared to checkerboard hybridization. Complete concordance was observed between the two methods at PIB VRs 1, 3, and 7. At the more degenerate VRs 5 and 6, PCR ELISA resulted in obtaining more typeable VRs than checkerboard hybridization due to single nucleotide mismatches. By PCR ELISA, two predominant PIB porB types were identified in 58% of the samples and the remaining 16 samples had one of six other porB types. Both PCR ELISA and checkerboard hybridization methods of porB VR typing allowed characterization of N. gonorrhoeae from noncultured clinical samples including throat and rectal swabs and discriminated N. gonorrhoeae from N. meningitidis present in some of the samples. PCR ELISA is a rapid, relatively inexpensive and alternative molecular typing method for N. gonorrhoeae, suitable for use in conjunction with molecular diagnostic tests.

Re-infection of Neisseria gonorrhoeae and Chlamydia trachomatis infections among men who have sex with men.

Our aim was to determine the incidence of re-infection of men who have sex with men (MSM) for rectal Neisseria gonorrhoeae (RNg) and rectal Chlamydia trachomatis (RCt) infection. The medical records of 126 MSM diagnosed with RNg or RCt infections at Melbourne Sexual Health Centre were reviewed. A total of 68 of the 126 (54%) MSM were re-tested. Among the HIV-positive MSM, 17 (81%) of 21 were re-tested and eight were positive (47%, 95% confidence interval [CI] 23-72%). Among the 51 (49%) of 105 of the HIV-negative or unknown MSM re-tested, 13 (25%, 14-40) were positive. Of the 21 infections identified, five cases were symptomatic. The incidence of rectal infections among MSM is high and prior RNg or RCt should be included as a risk factor for frequent screening.

Validation of roche COBAS Amplicor assay for detection of Chlamydia trachomatis in rectal and pharyngeal specimens by an omp1 PCR assay.

Screening guidelines for men who have sex with men (MSM) recommend testing of extragenital sites (pharyngeal and rectal) for gonorrhoea and chlamydia. Testing of specimens from these sites is not validated by most commercial nucleic amplification tests, such as the COBAS Amplicor assay. To investigate the utility of the COBAS Amplicor assay for detection of Chlamydia trachomatis in extragenital specimens, this study developed and evaluated confirmatory tests using the omp1 gene as an alternative target for amplification by PCR. Of anal and throat swabs collected from men in male-only saunas, 52 swabs that tested C. trachomatis positive by COBAS Amplicor and 30 swabs that tested as negative were included for confirmatory omp1 PCR testing. A total of 49 (94%) COBAS Amplicor-positive samples were confirmed by the omp1 PCR. A substantial proportion of specimens were confirmed by using a nested omp1 PCR (27%). Not confirmed by any omp1 PCR were three anal swabs (6%). It is most probable that these samples contained lower bacterial levels that were near or below the detection level of the omp1 PCR assays. The findings of this study support the confident reporting of C. trachomatis detected by COBAS Amplicor in extragenital specimens and support the utility of this assay as a screening test for MSM.

Testing men who have sex with men for Neisseria gonorrhoeae and Chlamydia trachomatis prior to the introduction of guidelines at an STD clinic in Melbourne.

BACKGROUND: Guidelines for testing men who have sex with men (MSM) were published in 2002. They did not recommend asymptomatic screening for urethral gonorrhoea or pharyngeal screening for chlamydia. To determine if these guidelines were appropriate, we audited gonorrhoea and chlamydia testing of MSM at our Centre. METHODS: We carried out two audits at our Centre between August 2001 and July 2002. The first was an audit of testing MSM for gonorrhoea and/or chlamydia over 12 days. The second was an audit of all positive tests over this 12-month period for gonorrhoea or chlamydia among MSM. RESULTS: During the 12 selected days 89 of 286 men tested (31%) were MSM. Among the MSM testing positive for gonorrhoea and/or chlamydia infection (15, 17%), symptomatic urethral infection was the most common (n = 8). No rectal and pharyngeal infections had site-specific symptoms. Based on the guidelines, 100 of the 334 tests ordered (30%) were not recommended according to the guidelines, and none of these 100 tests yielded a positive result. Over the 12-month audit period, 135 MSM were diagnosed with gonorrhoea and/or chlamydia. For gonorrhoea, site specific symptoms were present in 42 of 43 cases of urethral infection (98%), six of 23 cases of rectal infection (26%), and no cases of pharyngeal infection had symptoms. For chlamydia, site-specific symptoms were present in 29 of 48 cases of urethral infection (60%), six of 33 cases of rectal infection (18%), and in one of the two cases of pharyngeal chlamydia identified. A substantial proportion of cases occurred in clients with HIV infection (21, 16%). CONCLUSIONS: These findings strongly support screening among MSM and in particular not testing asymptomatic MSM for urethral gonorrhoea or any MSM for pharyngeal chlamydia.

Screening for Neisseria gonorrhoeae and Chlamydia trachomatis in men who have sex with men at male-only saunas.

BACKGROUND AND OBJECTIVES: In response to increases in sexually transmissible infections (STI) and HIV infection rates among men who have sex with men (MSM), the current study aimed to investigate the feasibility of a screening program at male-only saunas in Melbourne, Australia. GOAL: The goal was to determine (1) the participation rate, and the proportion whom obtain test results; (2) the prevalence of gonorrhea and chlamydia; and (3) to evaluate risk factors for STI acquisition. STUDY DESIGN: We used a cross-sectional design. Pharyngeal, rectal, and urethral specimens were collected from participants, and tested for Chlamydia trachomatis and Neisseria gonorrhoeae by polymerase chain reaction (PCR). RESULTS: There was a participation rate of 24% (n=521), and 70% obtained their test results. The infection rate in those who failed to collect their results was no different than those seeking theirs. The proportion of participants with PCR-detected gonorrhea and/or chlamydia infection was high, 10.7%. The presence of infection was associated with seeking sexual health care in the last year. CONCLUSION: The high prevalence rate of gonorrhea and chlamydia supports the concept of a screening program in Melbourne male-only saunas. The low participation rate has highlighted the need to consider alternative methods for making contact with men in the saunas or offering incentives to participate in future screening programs. Although anonymous participation encouraged participation for some men, future programs should attempt to obtain contact details for follow up of positive test results.

Peptide mimics as substrates for the intestinal peptide transporter.

4-Aminophenylacetic acid (4-APAA), a peptide mimic lacking a peptide bond, has been shown to interact with a proton-coupled oligopeptide transporter using a number of different experimental approaches. In addition to inhibiting transport of labeled peptides, these studies show that 4-APAA is itself translocated. 4-APAA transport across the rat intact intestine was stimulated 18-fold by luminal acidification (to pH 6.8) as determined by high performance liquid chromatography (HPLC); in enterocytes isolated from mouse small intestine the intracellular pH was reduced on application of 4-APAA, as shown fluorimetrically with the pH indicator carboxy-SNARF; 4-APAA trans-stimulated radiolabeled peptide transport in brush-border membrane vesicles isolated from rat renal cortex; and in Xenopus oocytes expressing PepT1, 4-APAA produced trans-stimulation of radiolabeled peptide efflux, and as determined by HPLC, was a substrate for translocation by this transporter. These results with 4-APAA show for the first time that the presence of a peptide bond is not a requirement for rapid translocation through the proton-linked oligopeptide transporter (PepT1). Further investigation will be needed to determine the minimal structural requirements for a molecule to be a substrate for this transporter.