Methods: Using retrospective records from Melbourne SHC, PID was clinically confirmed using CDC diagnostic criteria, with MG being the sole pathogen isolated. Only cases that received Moxifloxacin and had a test of cure (TOC) between Days 14-120 were included. These were compared to the CT-PID group.
Results: There were no significant demographic differences between the CT-PID and the MG-PID groups. There were also no significant differences in prevalence of any PID symptoms (e.g. abdominal pain, dyspareunia and inter-menstrual bleeding) between the two groups. The results were similar for signs of PID between the CT and MG-PID groups, with 2 exceptions: lower abdominal tenderness was more likely to be present in the MG-PID group (adjusted odds ratio 2.29, p=0.02), and vaginal PMN count being 1-4 (mid-range) was less likely in the MG-PID group (AOR 0.34, p=0.027). This last result is difficult to apply clinically as there were no differences in either the higher or lower vaginal PMN counts between the two groups.
Cure rates for Moxifloxacin were >95% on laboratory testing (NAAT-negative), and just under 90% for clinical cure (symptom resolution). Moxifloxacin adherence rates were 85%, and side effects were reported in 40% of patients.
Key Learnings:
This study is the largest data set of MG-PID cases. It did not find any clinically meaningful differences in presentation between MG and CT-PID and did show that Moxifloxacin for 14 days is highly effective in curing MG-PID.
This study suggests that clinical findings or lack of, cannot be relied upon to indicate causative organism in PID. It does however provide more supportive evidence for confidently using Moxifloxacin in treatment of MG-PID when there are currently no other effective treatment options. I would add that as treatment resistance increases, active follow up (i.e. Test Of Cure) is of great importance in these patients, although the debate will no doubt continue to increase as to the active management of their (often asymptomatic) contacts.
“Men who have sex with men with Mycoplasma genitalium are more likely to have macrolide resistant strains than men with only female partners: a prospective study”
This second, excellent presentation was by Ruthy McIver, a sexual health nurse in Sydney, and focused on a prospective study of 589 men with acute NGU.
Key Learnings:
- The prevalence of MG was (coincidentally) 12.8% in both MSM (n=39/306) and MSW (n=36/282) groups.
- Higher number of male sex partners was the only significant risk factor for the presence of MG (Odds Ratio 1.7). Interestingly, CT or gonorrhoea treatment in the last 12 months was not a factor (as well as age, condom use, sex of partners, HIV status, and PrEP use).
- Most MSM had macrolide resistance (90%). This was significantly higher than in the MSW group (50%).
- Age >30yrs (Odds Ratio 6.9), and male sex partners (OR 8.75) were both significant risk factors for Macrolide resistant MG
- 100% condom use was protective for Macrolide resistance (OR 0.3)
- No. of partners, HIV status, PrEP or CT/gonorrhea treatment in last 12 months was not associated with macrolide resistance.
- Reflection on how this might change my practice:
The takeaways form this session are that we must remember to test ALL patients with symptoms of urethritis for MG, and to conserve the use of azithromycin in treating NGU and other STIs, and that when available, MG treatment should be guided by real time resistance testing. This is yet to be available in many centres (including mine), but will be pivotal in improving treatment outcomes and for antimicrobial stewardship.
Author bio:
Victoria Hounsfield is the Senior CMO at Clinic 16, a Sexual Health clinic in Northern Sydney. She has specialised in Sexual Health/HIV in Australia/UK for over 10 years and has a large caseload of HIV and STI patients. She is actively involved in research and is currently researching Mycoplasma genitalium locally, as well as smoking in HIV patients. She recently set up PASHNET, a network of non-specialist doctors working in Sexual Health/HIV to promote better education and collaboration opportunities
