마크로라이드계 항생제 내성 및 Multilocus Sequence Typing 유전형 분석에 따른 국내 분리 마이코플라스마 폐렴균 현황, 2023-2024년

Objectives: strains isolated during the 2023-2024 epidemic in the Republic of Korea by analyzing macrolide resistance-associated mutations and multilocus sequence typing (MLST) genotypes. Methods: polymerase chain reaction (PCR)-positive specimens. In addition, 217 cultured isolates were further examined for resistant mutations and MLST genotypes. Results: , and 217 (16.8%) isolates were successfully cultured. The A2063G mutation was detected in 81.4% (351/431) of PCR-positive samples and 89.4% (194/217) of cultured isolates. MLST analysis identified four sequence types (STs): ST3 (89.9%) was predominant, followed by ST7 (6.5%), ST14 (1.8%), and ST17 (1.8%). The distribution of STs varied by resistant genotype, with ST3 (97.4%) predominating among resistant isolates and ST7 (52.2%) among susceptible isolates. Conclusions: isolates collected in the Republic of Korea during 2023-2024 exhibited high rates of macrolide resistance (89.4%), with ST3 as the predominant genotype. Distinct MLST distributions were observed between resistant and susceptible strains, underscoring the need for continuous molecular surveillance to monitor periodic outbreaks and shifts in genotype.