Frequency of macrolide resistance-associated mutations in Mycoplasma genitalium: a multicenter molecular analysis based in Brazil.

Mycoplasma genitalium is an emerging sexually transmitted pathogen with increasing antimicrobial resistance worldwide. In Brazil, molecular testing for M. genitalium and resistance-associated mutations is not routinely available, and national data remain scarce. We analyzed 118 M. genitalium-positive urethral and vaginal swab samples collected between 2018 and 2023 from sites across all five Brazilian geographic regions. PCR amplification and sequencing of 23S rRNA, parC, and gyrA identified macrolide and fluoroquinolone resistance-associated mutations. Among 79 samples successfully sequenced for 23S rRNA, 40.5% harbored macrolide resistance-associated mutations (A2058G, A2059G, or A2058T) detected in samples from all five regions at different frequencies. A total of 6.1% of sequenced samples presented parC mutations, including two with combined 23S rRNA and parC mutations. No resistance-associated mutations were detected in gyrA. While resistance-associated mutations occurred in both symptomatic men and pregnant women, these findings are not representative estimates for the Brazilian population since the study used convenience samples from two distinct surveillance populations. Nonetheless, they provide multicenter molecular data that may inform future surveillance, diagnostic strategies, antimicrobial stewardship, and resistance-guided management of M. genitalium in Brazil.