Abstract Objectives Antimicrobial resistance of Mycoplasma genitalium (MG) is a growing concern worldwide. Because reliable data on the burden of resistant MG in Belgium are missing, an additional prospective surveillance program was implemented in 2022 to estimate the real burden of resistant MG in Belgium. Methods Belgian laboratories (n=21) provided frozen remnants of MG positive samples to the National Reference Centre of Sexually Transmitted Infections from July to November 2022. The presence of macrolide and fluoroquinolones resistance associated mutations (RAMs) was assessed using Sanger sequencing of the 23SrRNA and parC gene. Differences in resistance patterns were correlated with surveillance methodology, socio-demographic and behavioral variables via Fisher’s exact test and logistic regression analysis. Results Sequencing for both macrolide and fluoroquinolone RAMs was successful for 232/244 MG positive samples. Over half of the samples were resistant to macrolides (55.2%). All MG in samples from men who have sex with men (MSM) (24/24) were resistant to macrolides. The presence of fluoroquinolone RAMs was estimated to be 26% and did not differ with socio-demographic and sexual behaviour characteristics. Conclusions Given the considerable cost of macrolide resistance testing, our data suggest that the use of macrolide resistance testing in MSM does not seem justified in Belgium. However, the lower prevalence of macrolide resistance in other population groups, combined with further emergence of fluoroquinolone resistance provides evidence for macrolide resistance testing in these groups. Continued surveillance of resistance in MG in all groups will be crucial to guide national testing- and treatment strategies.
Background Antimicrobial resistance (AMR) of Mycoplasma genitalium (MG) is a growing concern worldwide and surveillance is needed. In Belgium, samples are sent to the National Reference Centre of Sexually Transmitted Infections (NRC-STI) on a voluntary basis and representative or robust national AMR data are lacking. Aim We aimed to estimate the occurrence of resistant MG in Belgium. Methods Between July and November 2022, frozen remnants of MG-positive samples from 21 Belgian laboratories were analysed at the NRC-STI. Macrolide and fluoroquinolone resistance-associated mutations (RAMs) were assessed using Sanger sequencing of the 23SrRNA and parC gene. Differences in resistance patterns were correlated with surveillance methodology, socio-demographic and behavioural variables via Fisher’s exact test and logistic regression analysis. Results Of the 244 MG-positive samples received, 232 could be sequenced for macrolide and fluoroquinolone RAMs. Over half of the sequenced samples (55.2%) were resistant to macrolides. All sequenced samples from men who have sex with men (MSM) (24/24) were macrolide-resistant. Fluoroquinolone RAMs were found in 25.9% of the samples and occurrence did not differ between socio-demographic and sexual behaviour characteristics. Conclusion Although limited in sample size, our data suggest no additional benefit of testing MG retrieved from MSM for macrolide resistance in Belgium, when making treatment decisions. The lower occurrence of macrolide resistance in other population groups, combined with emergence of fluoroquinolone RAMs support macrolide-resistance testing in these groups. Continued surveillance of resistance in MG in different population groups will be crucial to confirm our findings and to guide national testing and treatment strategies.