Mycoplasma genitalium coinfection in men with symptomatic gonococcal urethritis.

OBJECTIVES: International guidelines recommend Mycoplasma genitalium testing, preferably using an assay to detect macrolide resistance-associated mutations, for men presenting with non-gonococcal urethritis, but there is no specific guidance on such testing for men with gonococcal urethritis. METHODS: This study aimed to estimate the proportion of men with gonococcal urethritis who have coinfection with M. genitalium through a retrospective analysis of cases of symptomatic urethral gonorrhoea at Western Sydney Sexual Health Centre in 2017 and 2018. RESULTS: Fourteen of 184 (7.6%, 95% CI 3.7 to 11.5) men with gonococcal urethritis had M. genitalium detected in the urine at the time of presentation. No demographic or behavioural factors predicted M. genitalium coinfection. Coinfection with urethral Chlamydia trachomatis was detected in 29 of 184 (15.8%, 95% CI 10.5 to 21.1). All five men with macrolide-resistant M. genitalium detected returned for treatment with moxifloxacin at a median of 8 days (range 5-16 days) after presentation and treatment of gonorrhoea; three of five were documented to remain symptomatic at this visit. CONCLUSION: Although M. genitalium coinfection is less common than chlamydia among men with symptomatic gonococcal urethritis, M. genitalium testing, using an assay to detect macrolide resistance, will potentially reduce symptom duration particularly for men with macrolide-resistant infections, but may not be justifiable on cost-benefit analysis.

Men Who Have Sex With Men With Mycoplasma genitalium-Positive Nongonococcal Urethritis Are More Likely to Have Macrolide-Resistant Strains Than Men With Only Female Partners: A Prospective Study.

BACKGROUND: Mycoplasma genitalium was previously less common among men who have sex with men (MSM) compared with men with only female partners (MSW) in men with nongonococcal urethritis (NGU) in Sydney, Australia. We aimed to determine the prevalence of M. genitalium and of macrolide-resistant M. genitalium in men with NGU and to compare differences between prevalence and resistance rates between MSM and MSW. METHODS: We enrolled 588 men with NGU in a prospective study at two urban sexual health services. The ResistancePlus MG assay (SpeeDx, Australia) was used to detect both M. genitalium, and macrolide resistance-associated mutations in first-void urine samples. Demographic, behavioral and clinical data were analyzed to investigate associations with M. genitalium infection or the presence of macrolide resistance. RESULTS: Mycoplasma genitalium prevalence was 12.8% (75 of 588) overall and among MSM (12.8% [39 of 306]) and MSW (12.8% [36 of 282]; risk ratio [RR], 1.00; 95% confidence interval [CI], 0.65-1.52). Overall, 70.7% (53 of 75) of M. genitalium strains were macrolide-resistant, with significantly more resistance among MSM (89.7%, 35 of 39) than MSW (50%, 18 of 36) (RR, 1.80; 95% CI, 1.27-2.54; P = 0.001). On multivariate analysis, the presence of M. genitalium macrolide resistance mutations was independently associated with having male sexual partners compared with having only female partners (RR, 1.55; 95% CI, 1.02-2.38; P = 0.042). CONCLUSIONS: Prevalence of M. genitalium among men with NGU is now similar for MSW and MSM and has increased locally from 5.2% to 12.8% within the last 10 years. Men who have sex with men are significantly more likely than MSW to harbor macrolide-resistant M. genitalium infections. This has treatment implications.

Mycoplasma genitalium: high prevalence of resistance to macrolides and frequent anorectal infection in men who have sex with men in western Sydney.

OBJECTIVES: We aimed to estimate the prevalence of Mycoplasma genitalium infection and of mutations linked to macrolide resistance using the ResistancePlus MG assay (SpeeDx, Sydney, New South Wales, Australia) in first-void urine (FVU), anorectal and oropharyngeal samples from men who have sex with men (MSM) attending Western Sydney Sexual Health Centre (WSSHC). METHODS: Consecutive symptomatic and asymptomatic MSM attending for STI testing were prospectively enrolled. M. genitalium testing using the ResistancePlus MG assay was performed on FVU, anorectal and oropharyngeal samples routinely collected for Chlamydia trachomatis and Neisseria gonorrhoeae assays. RESULTS: Overall, the prevalence of M. genitalium infection in the study group was 13.4% (68/508). Most (79.4%, 54/68) M. genitalium harboured macrolide resistance mutations (87.5% of urethral and 75.6% of anorectal infections). The anorectum was the most commonly infected site (45/505, 8.9%), followed by the urethra (24/508, 4.7%). No oropharyngeal M. genitalium infections were detected (0/508). Most of the anorectal (93.3%) and urethral (79.2%) infections were asymptomatic.MSM who were taking HIV pre-exposure prophylaxis (PrEP) were twice as likely to be infected with M. genitalium compared with MSM who were not on PrEP (OR 2.1, 95% CI 1.3 to 3.6; P=0.0041). Always using condoms for anal sex in the last 3 months was protective of infection (OR 0.8, 95% CI 0.6 to 1.0; P=0.0186). CONCLUSIONS: We demonstrated a high prevalence of M. genitalium and very high levels of macrolide resistance among MSM attending WSSHC. Our findings support the routine use of an assay to detect macrolide resistance mutations in M. genitalium infections. This will ensure, in regions or populations with high rates of macrolide resistance among M. genitalium strains, that first-line treatment with azithromycin will only be used if a macrolide-sensitive strain is identified.

Failure of moxifloxacin treatment in Mycoplasma genitalium infections due to macrolide and fluoroquinolone resistance.

Increasing azithromycin treatment failure in sexually transmitted Mycoplasma genitalium infection, is linked to macrolide resistance and second-line treatment relies on the fluoroquinolone, moxifloxacin. We recently detected fluoroquinolone and macrolide resistance-associated mutations in 15% and 43%, respectively, of 143 initial M. genitalium PCR-positive specimens. For a subset of 33 Western Sydney Sexual Health Centre patients, clinical information and results of sequence analysis of M. genitalium macrolide and fluoroquinolone target genes - the 23S rRNA gene, and parC and gyrA, respectively - were used to examine whether mutations were associated with treatment failure. Macrolide resistance-associated mutations correlated with microbiological (p = 0.013) and clinical (p = 0.024) treatment failure, and fluoroquinolone resistance-associated mutations with microbiological moxifloxacin treatment failure (p = 0.005). We describe the first reported cases of clinical and microbiological moxifloxacin treatment failure. Failure of first- and second-line antibiotic treatment of M. genitalium infection is occurring and likely to increase with current treatment strategies.

Fluoroquinolone and macrolide resistance-associated mutations in Mycoplasma genitalium.

Mycoplasma genitalium is a significant sexually transmitted pathogen, causing up to 25% of cases of nongonococcal urethritis in men, and it is strongly associated with cervicitis and pelvic inflammatory disease in women. Currently, the usual first-line treatment is the macrolide antibiotic azithromycin, but an increasing incidence of treatment failure over the last 5 years suggests the emergence of antibiotic resistance. The mutations responsible for macrolide resistance have been found in the 23S rRNA gene in numerous M. genitalium populations. A second-line antibiotic, the fluoroquinolone moxifloxacin, was thought to be a reliable alternative when azithromycin began to fail, but recent studies have identified mutations that may confer fluoroquinolone resistance in the genes parC and gyrA. The aim of this study was to determine the prevalence of antibiotic resistance in M. genitalium in Sydney, Australia, by detecting relevant mutations in the 23S rRNA gene, parC, and gyrA. M. genitalium-positive DNA extracts of specimens, collected from patients attending sexual health clinics in Sydney, were tested by PCR amplification and DNA sequence alignment. The 186 specimens tested included 143 initial patient specimens and 43 second, or subsequent, specimens from 24 patients. We identified known macrolide resistance-associated mutations in the 23S rRNA gene in 43% of the initial patient samples and mutations potentially associated with fluoroquinolone resistance in parC or gyrA sequences in 15% of the initial patient samples. These findings support anecdotal clinical reports of azithromycin and moxifloxacin treatment failures in Sydney. Our results indicate that further surveillance is needed, and testing and treatment protocols for M. genitalium infections may need to be reviewed.

A longitudinal evaluation of Treponema pallidum PCR testing in early syphilis.

BACKGROUND: Syphilis is a growing public health problem among men who have sex with men (MSM) globally. Rapid and accurate detection of syphilis is vital to ensure patients and their contacts receive timely treatment and reduce ongoing transmission. METHODS: We evaluated a PCR assay for the diagnosis of Treponema pallidum using swabs of suspected early syphilis lesions in longitudinally assessed MSM. RESULTS: We tested 260 MSM for T pallidum by PCR on 288 occasions: 77 (26.7%) had early syphilis that was serologically confirmed at baseline or within six weeks, and 211 (73.3%) remained seronegative for syphilis. Of 55 men with primary syphilis, 49 were PCR positive, giving a sensitivity of 89.1% (95% CI: 77.8%-95.9%) and a specificity of 99.1% (95% CI: 96.5%-99.9%). Of 22 men with secondary syphilis, 11 were PCR positive, giving a sensitivity of 50% (95% CI: 28.2%-71.8%) and a specificity of 100% (95% CI: 66.4%-71.8%). Of the 77 syphilis cases, 43 (56%) were HIV positive and the sensitivity and specificity of the PCR test did not vary by HIV status. The PCR test was able to detect up to five (10%) primary infections that were initially seronegative, including one HIV positive man with delayed seroconversion to syphilis (72 to 140 days) and one HIV positive man who did not seroconvert to syphilis over 14 months follow-up. Both men had been treated for syphilis within a week of the PCR test. CONCLUSIONS: T pallidum PCR is a potentially powerful tool for the early diagnosis of primary syphilis, particularly where a serological response has yet to develop.