Araj George F, Baba Omar Z, Itani Lina Y, Avedissian Aline Z, Sobh Ghena M
Department of Pathology and Laboratory Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
J Infect Dev Ctries. 2019 Jul 31;13(7):612-618. doi: 10.3855/jidc.11028.
Infection with non-tuberculosis mycobacteria (NTM) has been on the rise globally causing a wide spectrum of respiratory and extrapulmonary infections in humans. Studies on these pathogens from the Middle-East including Lebanon are scarce.
This retrospective study addresses the approach used for investigation, speciation and antimicrobial resistance (AMR) profiles of recovered NTM isolates from respiratory sources at a major tertiary care center in Lebanon during two periods (2003-2007 and 2013-2017). Processing of specimens, culture and differentiation of recovered NTM isolates from Mycobacterium tuberculosis were done in-house according to standard procedures. Upon request, speciation and AMR testing were performed using molecular and broth dilution methods, respectively, at Mayo Medical Laboratories (Rochester, Minnesota, USA).
Among 108 NTM analyzed isolates, 8 species were revealed during the two periods: M. simiae (51% vs 61%), M. avium complex (MAC) (6 % vs 12%) M. fortuitum (12% vs 5%), M. gordonae (6% vs 5%), M. abscessus (6% vs 7%), M. immunogenum (12% vs 0%), M. szulgai (4% vs 0%) and M. peregrinum (0% vs 2%). M. simiae isolates showed high susceptibility (93%-96%) to amikacin and clarithromycin, but high resistance to rifampin, ethambutol, ciprofloxacin, rifabutin, linezolid, trimethoprim/sulfamethoxazole and moxifloxacin. MAC isolates were only susceptible to clarithromycin (86%). M. abscessus isolates were uniformly susceptible to amikacin (100%).
The revelaed different NTM species, with predominance of M.simiae and various AMR profiles provide a current epidemiologic database and help guiding the selection of appropriate empirical therapy once the clinical relevance is established.
非结核分枝杆菌（NTM）感染在全球范围内呈上升趋势，可导致人类多种呼吸道和肺外感染。包括黎巴嫩在内的中东地区对这些病原体的研究较少。
这项回顾性研究探讨了黎巴嫩一家主要三级护理中心在两个时期（2003 - 2007年和2013 - 2017年）从呼吸道来源回收的NTM分离株的调查方法、菌种鉴定和抗菌药物耐药性（AMR）谱。标本处理、培养以及从结核分枝杆菌中区分回收的NTM分离株均按照标准程序在内部进行。应要求，分别在美国明尼苏达州罗切斯特市的梅奥医学实验室使用分子方法和肉汤稀释法进行菌种鉴定和AMR检测。
在分析的108株NTM分离株中，两个时期共鉴定出8种：西氏分枝杆菌（51%对61%）、鸟分枝杆菌复合群（MAC）（6%对12%）、偶然分枝杆菌（12%对5%）、戈登分枝杆菌（6%对5%）、脓肿分枝杆菌（6%对7%）、免疫分枝杆菌（12%对0%）、斯氏分枝杆菌（4%对0%）和 Peregrinum分枝杆菌（0%对2%）。西氏分枝杆菌分离株对阿米卡星和克拉霉素显示出高敏感性（93% - 96%），但对利福平、乙胺丁醇、环丙沙星、利福布汀、利奈唑胺、甲氧苄啶/磺胺甲恶唑和莫西沙星具有高耐药性。MAC分离株仅对克拉霉素敏感（86%）。脓肿分枝杆菌分离株对阿米卡星均敏感（100%）。
所揭示的不同NTM菌种，以西氏分枝杆菌为主以及各种AMR谱，提供了当前的流行病学数据库，并有助于在确定临床相关性后指导选择合适的经验性治疗。
