Clinical Microbiology and Antimicrobial Chemotherapy. 2026; 28(2):309-319
To study prevalence of macrolide resistance mutations in Mycoplasma pneumoniae isolated from children with community-acquired pneumonia in Smolensk region.
The study included 774 M. pneumoniae-positive samples isolated by realtime polymerase chain reaction (real-time PCR) from pharyngeal swab in children with communityacquired pneumonia over the period 2009–2024, including 3 epidemiological rises in the incidence of M. pneumoniae (2013–2014, 2018–2019, 2023–2024). Samples of isolated DNA were examined for nucleotide substitutions in the 23S rRNA gene at positions 2058, 2059, 2611 (E. coli numbering) using real-time PCR technology with the effect of quenching of probe fluorescence by primer. To confirm the nature of the substitution, all M. pneumoniae DNA samples carrying mutations were additionally examined by sequencing.
The prevalence of mutations to macrolides in M. pneumoniae was 23.4% (181⁄774). No macrolide resistance-associated mutations were detected in 2013–2014. Mutations were first detected in October 2017 (6.6%) during the second epidemiological upsurge, with significant increases in 2018 (35.3%) and 2019 (30.9%). After a decrease in M. pneumoniae registrations in 2020–2022, an increase in incidence and an increase in mutations (13.8%) is noted in 2023, the third upsurge in the incidence rate. The highest level of mutations is registered during epidemic rises in incidence. The predominant variant of mutations is A2058G 81,2% (147⁄181), in 5,4 times less frequently revealed mutation A2059G 14,9% (27⁄181). A rare type of nucleotide substitutions was detected: A2062C 1.1% (2⁄181). Of particular note is the genotype consisting of two mutation types A2059G + A2058G 1.6% (3⁄181), A2059G + A2062C 0.5% (1⁄181), and three mutations simultaneously: A2059G + A2058G + A2062C 0.5% (1⁄181). Results of multicenter study «DeMaRes» are available on the AMRcloud platform (https://amrcloud.net/ru/project/demares/).
Proportion of M. pneumoniae carrying macrolides resistance mutations increases during epidemic outbreaks. Continuous monitoring of M. pneumoniae incidence data and identification of mutations causing antibiotic resistance is critical for treatment success.