Successful antibiotic treatment of pulmonary disease caused by Mycobacterium abscessus subsp. abscessus with C-to-T mutation at position 19 in erm(41) gene: case report. Issue 1 (December 2016)

• Record Type: Journal Article
• Authors: Kim, Su-Young; Shin, Sung; Jeong, Byeong-Ho; Koh, Won-Jung
• Is Part Of: BMC infectious diseases. Volume 16:Issue 1(2016)
• Page Start: 1
• Page End: 5
• Publication Date: 2016-12
• Subjects: Nontuberculous mycobacteria -- Mycobacterium abscessus -- Lung diseases -- Clarithromycin -- Drug resistance; Communicable diseases -- Periodicals; Sexually Transmitted Diseases -- Periodicals; 616.905
• DOI: 10.1186/s12879-016-1554-7
• Languages: English
• ISSNs: 1471-2334

Abstract

Abstract Background Mycobacterium abscessus complex (MABC) is the most drug resistant of the mycobacterial pathogens.M. abscessus subsp.abscessus encodes a functional erythromycin ribosomal methylase gene, erm (41), causing inducible macrolide resistance. However, some clinical isolates ofM. abscessus subsp.abscessus harboring nonfunctionalerm (41) were susceptible to macrolide, even after extended incubation of 14 days. Loss of function of theerm (41) genes was associated with a T-to-C substitution at position 28 of the gene (T28C), leading to an amino acid change from Trp to Arg at codon 10. Pulmonary disease caused byM. abscessus subsp.abscessus strains with an nonfunctionalerm (41) (C28 sequevar) may be responsive to macrolide-containing antibiotic regimens. Therefore, allM. abscessus subsp.abscessus strains with a functionalerm (41) (T28 sequevar) were thought to be resistant to macrolide with extended incubation. Here, we report the first case of pulmonary disease caused by a strain ofM. abscessus subsp.abscessus which was susceptible to macrolide due to T19 sequevar oferm (41) gene. Case presentation A 62-year-old Korean female was referred to our hospital due to chronic cough, sputum, and hemoptysis lasting more than 5 months. The patient's sputum was positive for acid-fast bacilli staining and nontuberculous mycobacteria (NTM) were isolated twice from sputum specimens. The isolate was identified asM. abscessus subsp.abscessus . The isolate had a point mutation of C → T at position 19 (C19 → T) in theerm (41) gene, instead of expected C28 sequevar oferm (41), and had norrl mutation. The isolate displayed a clarithromycin susceptible phenotype with an Arg → Stop codon change inerm (41). The patient was successfully treated with a macrolide-containing regimen. Conclusion This is the first case of pulmonary disease caused by a strain ofM. abscessus subsp.abscessus showing clarithromycin susceptible phenotype due to T19 sequevar of theerm (41) gene. Theerm (41) gene is clinically important, and non-functionalerm alleles may be an important issue for the management of MABC lung disease. The presence of a non-functionalerm (41) allele inM. abscessus subsp.abscessus isolates may be associated with better outcomes.