비결핵항산균의 임상 및 미생물학적 특성과 항균제 내성 양상에 관한 연구 = CLINICAL AND MICROBIOLOGICAL CHARACTERISTICS OF NONTUBERCULOUS MYCOBACTERIA AND THEIR ANTIMICROBIAL RESISTANCE PATTERN

다국어 초록 (Multilingual Abstract)

Purpose: The aim of this study is to describe the clinical and microbiological characteristics of nontuberculous mycobacteria (NTM) isolated in a single tertiary hospital, and to summarize antimicrobial susceptibility test (AST) and resistance patterns based on minimum inhibitory concentration (MIC) testing.
Methods: This retrospective study included 212 patients whose NTM species were isolated and tested for antimicrobial susceptibility at Daegu Catholic University Medical Center from September 2019 to August 2025. Medical records for age, sex, symptoms, underlying diseases, and radiologic findings were reviewed. NTM species were identified by PCR hybridization, and AST was performed by broth microdilution and interpreted using CLSI criteria. For Mycobacterium abscessus complex (MABC), inducible resistance (IR) to clarithromycin was evaluated by reading results on day 3 and day 14.
Results: The median age of patients was 72, and 54.2% were female. Nodular/bronchiectatic findings were frequent (86.3%), and 44 patients (20.8%) received treatment. The most common NTM species was Mycobacterium avium complex (MAC, n=143, 67.5%), followed by MABC (n=19, 9.0%) and M. kansasii(n=13, 6.1%). In MAC, clarithromycin susceptibility was 100%, while amikacin susceptibility was around 70%. In MABC, there was a clear difference between subspecies; 91.7% of M. abscessus showed inducible resistance to clarithromycin, but 91.7% of M. massiliense remained susceptible. Both subspecies of MABC showed high susceptibility to amikacin (75-91.7%).
Conclusions: MAC is the most frequent species among NTM patients in this study. For MABC, subspecies identification is essential for choosing the right antibiotics because clarithromycin resistance patterns are very different between M. abscessus and M. massiliense. Analyzing MIC distribution, not just susceptibility rates, is helpful to understand the characteristics of each antibiotic and to establish better treatment strategies for NTM lung disease.

목차 (Table of Contents)

• (Abstract)
• Ⅰ. 서 론 1
• Ⅱ. 연구 재료 및 방법 3
• Ⅲ. 결 과 7
• Ⅳ. 고 찰 18
• Ⅴ. 참고문헌 24