We report a high azithromycin failure rate (39%) in an M. genitalium-infected cohort in association with high levels of pretreatment macrolide resistance. Moxifloxacin failure occurred in 12% of patients who received moxifloxacin; all had pretreatment fluoroquinolone mutations detected. Pristinamycin was highly effective in treating macrolide- and quinolone-resistant strains.

Escalating resistance to azithromycin and moxifloxacin is being reported for Mycoplasma genitalium in the Asia-Pacific region. Analyzing 140 infections, we found pretreatment fluoroquinolone-resistance mutations in parC (13.6%) and gyrA (5%). ParC S83 changes were associated with moxifloxacin failure. Combined macrolide/fluoroquinolone-resistance mutations were in 8.6% of specimens, for which recommended therapies would be ineffective.

The bacterial loads for gonococcal infections of the pharynx and rectum were determined among men with male sexual partners. The median bacterial load for rectal infections (18,960 copies/swab) was significantly higher than the load for pharyngeal infections (2,100 copies/swab; P ‫؍‬ 0.001). Bacterial loads among men with symptomatic proctitis were strikingly high (median, 278,000 copies/swab).Gonorrhea is one of the most common sexually transmitted diseases, and study results suggest that rectal gonorrhea enhances HIV transmission (1-3).There are limited data on the transmissibility of gonorrhea, particularly from the pharynx and rectum. To examine potential transmissibility from these sites, we measured gonococcal bacterial loads and examined associated clinical and laboratory factors.All men who have sex with men (MSM) attending the Melbourne Sexual Health Centre between January 2010 and April 2010 who underwent testing for sexually transmitted infections were included. Pharyngeal and rectal specimens were obtained using cotton-tipped swabs. Rectal specimens were obtained either by blind anal swabbing or, in men with symptomatic proctitis, via anoscopy. Swabs were plated onto modified Thayer-Martin medium, placed into phosphate-buffered saline, and then analyzed using real-time quantitative PCR (qPCR) targeting the opa gene of Neisseria gonorrhoeae (4). Positive PCR tests were confirmed using real-time PCR targeting the gonococcal porA pseudogene (7). Gonococcal loads were quantified by comparing the crossing threshold for each sample to the crossing threshold of a standard curve constructed by amplifying different, known copy numbers of N. gonorrhoeae in an opa assay. To determine the adequacy of sample collection, a qPCR targeting the 260-bp region of ␤-globin was performed.Inoculated culture plates were incubated at 36°C in 5% CO 2 for 48 h. Presumptive N. gonorrhoeae colonies were oxidase tested, and identification of specimens to the species level was confirmed by carbohydrate reaction tests. Specimens that were culture positive and/or PCR positive were regarded as representing true infections. The McNemar test was used to compare detection of gonorrhea by culture versus PCR. The Mann-Whitney test was used to compare bacterial loads. The Human Research Ethics Committee of the Alfred Hospital approved the study.Specimens were obtained from 1,076 MSM. The median age of the subjects was 32 (range, 18 to 69). For testing using both culture and PCR, 1,011 rectal and 1,076 pharyngeal specimens were obtained. There were 43 (3.9%) confirmed PCR-positive pharyngeal specimens, of which 17 were also culture positive (sensitivity, 39%). There were 47 (4.6%) confirmed PCR-positive rectal specimens, of which 25 were also culture positive (sensitivity, 53%).Twelve men had concurrent gonorrheal infections of the pharynx and rectum. A further 10 were concurrently infected at the urethra and rectum, while 2 were concurrently infected at the urethra, pharynx, and rectum. Five men were coinfected with rectal chlamydia and g...

Extended azithromycin 1.5g was no more effective than a single 1g dose at achieving cure of M. genitalium urethritis and importantly did not reduce the selection of macrolide resistance. Nonmacrolide and new approaches for the treatment of M. genitalium urethritis are required.

This study examined the contribution of Mycoplasma genitalium to sexually acquired infectious proctitis in men who have sex with men (MSM). MSM with symptomatic proctitis between May 2012 and August 2013 were tested for rectal sexually transmitted infections including chlamydia, gonorrhoea, herpes simplex virus (HSV) and M. genitalium. The load of rectal M. genitalium in men with symptomatic proctitis was compared with a separate group of men who had rectal M. genitalium but no symptoms of proctitis. Among 154 MSM with proctitis, rectal M. genitalium was detected in 18 men (12%, 95% CI 6.9-17.1) and was significantly more common among human immunodeficiency virus (HIV) -positive men (21%, 95% CI 9.5-32.6) than HIV-negative men (8%, 95% CI 2.9-13.1; prevalence ratio 3.2, 95% CI 1.2-8.8). Among HIV-positive men the detection of M. genitalium was comparable to that for chlamydia (21%, 95% CI 9.5-32.5), gonorrhoea (25%, 95% CI 16.2-41.8) and HSV (19%, 95% CI 7.9-30.1). Rectal M. genitalium load was significantly higher among the 18 men with symptomatic M. genitalium-associated proctitis than among a separate group of 18 men with asymptomatic rectal M. genitalium infection (60 000 copies of organism/swab versus 10 744 copies of organism/swab, p 0.023). Comprehensive testing for rectal pathogens in MSM with proctitis should include testing for M. genitalium.

The inclusion of routine syphilis serology with every blood test performed as part of HIV monitoring in HIV-positive MSM resulted in a large increase in the proportion of men diagnosed with early asymptomatic syphilis. This simple intervention probably also decreased the duration of infectiousness, enhancing syphilis control while also reducing morbidity.

Mycoplasma genitalium is a cause of non-gonoccocal urethritis (NGU) in men and cervicitis and pelvic inflammatory disease in women. Recent international data also indicated that the first line treatment, 1 gram stat azithromycin therapy, for M. genitalium is becoming less effective, with the corresponding emergence of macrolide resistant strains. Increasing failure rates of azithromycin for M. genitalium has significant implications for the presumptive treatment of NGU and international clinical treatment guidelines. Assays able to predict macrolide resistance along with detection of M. genitalium will be useful to enable appropriate selection of antimicrobials to which the organism is susceptible and facilitate high levels of rapid cure. One such assay recently developed is the MG 23S assay, which employs novel PlexZyme™ and PlexPrime™ technology. It is a multiplex assay for detection of M. genitalium and 5 mutations associated with macrolide resistance. The assay was evaluated in 400 samples from 254 (186 males and 68 females) consecutively infected participants, undergoing tests of cure. Using the MG 23S assay, 83% (331/440) of samples were positive, with 56% of positives carrying a macrolide resistance mutation. Comparison of the MG 23S assay to a reference qPCR method for M. genitalium detection and high resolution melt analysis (HRMA) and sequencing for detection of macrolide resistance mutations, resulted in a sensitivity and specificity for M. genitalium detection and for macrolide resistance of 99.1/98.5% and 97.4/100%, respectively. The MG 23S assay provides a considerable advantage in clinical settings through combined diagnosis and detection of macrolide resistance.

Gonococcal loads in men with urethral discharge were higher than loads seen with asymptomatic urethral gonorrhoea and loads seen in asymptomatic pharyngeal and rectal gonorrhoea infections in previous studies.