Puga Fernanda Guioti, Pocente Renata Helena Candido, Chimara Erica, Bollela Valdes Roberto
Ribeirão Preto School of Medicine, University of São Paulo (FMRP-USP), Ribeirão Preto, Brazil.
Mycobacteria Laboratory of Ribeirão Preto School of Medicine, University of São Paulo, Ribeirão Preto, Brazil.
J Thorac Dis. 2018 Mar;10(3):1903-1911. doi: 10.21037/jtd.2018.03.66.
Nontuberculous mycobacteria (NTM) have been identified with increasing frequency in the clinical practice. The aim of this study was to characterize NTM isolates in respiratory specimens from patients with pulmonary disease and to correlate this with clinical/radiological findings, decision to start treatment and outcomes.
A cross-sectional descriptive study was performed and included all patients who had at least one NTM isolated in respiratory specimens between 2011 and 2014. NTM culture was performed in liquid medium followed by immunochromatographic identification (anti-MPT64). Species identification was based on nucleic acid amplification followed by restriction analysis of a 441 bp fragment of the hsp65 gene (hsp65 PRA) and patients' records were reviewed.
From 14,394 cultures in 4 years, 590 (4.10%) grew NTM and 305 (51.7%) isolates were characterized till species level, representing 290 patients including those with and without human immunodeficiency virus (HIV) infection. Two hundred and eleven non-HIV patients had NTM isolated from respiratory specimens, 49 (23.2%) had criteria for active disease based on the American Thoracic Society (ATS) 2007. The majority was men above 51 years old and M. intracellulare was detected in 59.2% (29/49), followed by M. avium 14.3% (7/49), and M. abscessus 12.2% (6/49).
Old age, nodular and nodular/bronchiectasis radiographic pattern, previous tuberculosis (TB) treatment and M. intracellulare were more frequent among NTM-disease patients compared to those only colonized. Positive culture and maintenance of clinical symptoms (poor outcome) was a rule when M. abscessus caused NTM-disease. Positive acid-fast smear in respiratory specimen is a strong predictor of disease.
非结核分枝杆菌（NTM）在临床实践中的检出频率日益增加。本研究旨在对肺部疾病患者呼吸道标本中的NTM分离株进行特征分析，并将其与临床/放射学表现、开始治疗的决策及治疗结果相关联。
进行了一项横断面描述性研究，纳入了2011年至2014年间呼吸道标本中至少分离出一株NTM的所有患者。在液体培养基中进行NTM培养，随后进行免疫色谱鉴定（抗MPT64）。基于核酸扩增及hsp65基因441bp片段的限制性分析（hsp65 PRA）进行菌种鉴定，并查阅患者记录。
4年间共进行了14394次培养，590次（4.10%）培养出NTM，其中305株（51.7%）分离株鉴定到菌种水平，涉及290例患者，包括合并和未合并人类免疫缺陷病毒（HIV）感染的患者。211例非HIV患者呼吸道标本中分离出NTM，根据美国胸科学会（ATS）2007年标准，49例（23.2%）有活动性疾病标准。大多数为51岁以上男性，胞内分枝杆菌检出率为59.2%（29/49），其次是鸟分枝杆菌14.3%（7/49），脓肿分枝杆菌12.2%（6/49）。
与仅为定植的患者相比，NTM疾病患者中老年人、结节状及结节状/支气管扩张影像学表现、既往结核病（TB）治疗史及胞内分枝杆菌更为常见。脓肿分枝杆菌引起NTM疾病时，培养阳性且临床症状持续（预后不良）是规律。呼吸道标本抗酸涂片阳性是疾病的有力预测指标。
