Wu Jie, Zhang Yangyi, Li Jing, Lin Senlin, Wang Lili, Jiang Yuan, Pan Qichao, Shen Xin
Department of TB Control, Shanghai Municipal Center for Disease Control and Prevention, Shanghai, China.
PLoS One. 2014 Oct 16;9(10):e109736. doi: 10.1371/journal.pone.0109736. eCollection 2014.
In China, the prevalence of nontuberculous mycobacteria (NTM) in isolates from mycobacterial culture-positive patients with pulmonary tuberculosis (TB) is largely unknown.
We used conventional biochemical and 16S rRNA gene sequencing to identify species of mycobacteria in specimens from patients suspected of having TB. Drug-susceptibility testing was performed on NTM isolates using the proportion method. We also determined the independent risk factors associated with infection with NTM compared with infection with Mycobacterium tuberculosis.
The overall rate of NTM isolated from mycobacterial culture-positive patients was 5.9% in this population, with a significantly increasing trend from 3.0% in 2008 to 8.5% in 2012 (P for trend <0.001). The organism most frequently identified was M. kansasii (45.0%), followed by M. intracellulare (20.8%) and M. chelonae/abscessus (14.9%). The overall proportion of isolates resistant to the four first-line anti-TB agents were 64.6% for isoniazid, 77.6% for streptomycin, 63.3% for rifampicin and 75.1% for ethambutol. The risk factors most often associated with NTM infection were older age (P for trend <0.001), being a resident of Shanghai (adjusted odds ratio [aOR], 1.48; 95% CI, 1.10-2.00), having been treated for tuberculosis (aOR, 1.64; 95% CI, 1.18-2.29), having a cavity on chest X-ray (aOR, 1.51; 95% CI, 1.16-1.96), and being sputum smear-negative (aOR, 1.59; 95% CI, 1.16-2.18).
The prevalence of NTM isolated in Shanghai increased between 2008 and 2012, thus clinicians should consider NTM as a possible cause of TB-like disease. Accurate species identification is imperative so that proper treatment can be administered for diseases caused by the diversity of NTM species.
在中国，肺结核（TB）分枝杆菌培养阳性患者分离出的非结核分枝杆菌（NTM）的流行情况很大程度上未知。
我们使用传统生化方法和16S rRNA基因测序来鉴定疑似患有结核病患者标本中的分枝杆菌种类。对NTM分离株采用比例法进行药敏试验。我们还确定了与结核分枝杆菌感染相比，与NTM感染相关的独立危险因素。
在该人群中，从分枝杆菌培养阳性患者中分离出NTM的总体率为5.9%，从2008年的3.0%到2012年的8.5%有显著上升趋势（趋势P<0.001）。最常鉴定出的菌株是堪萨斯分枝杆菌（45.0%），其次是胞内分枝杆菌（20.8%）和龟分枝杆菌/脓肿分枝杆菌（14.9%）。对四种一线抗结核药物耐药的分离株总体比例分别为：异烟肼64.6%、链霉素77.6%、利福平63.3%、乙胺丁醇75.1%。与NTM感染最常相关的危险因素是年龄较大（趋势P<0.001）、上海居民（调整优势比[aOR]，1.48；95%可信区间[CI]，1.10 - 2.00）、曾接受过结核病治疗（aOR，1.64；95%CI，1.18 - 2.29）、胸部X线有空洞（aOR，1.51；95%CI，1.16 - 1.96）以及痰涂片阴性（aOR，1.59；95%CI，1.16 - 2.18）。
2008年至2012年期间上海分离出的NTM患病率有所上升，因此临床医生应将NTM视为类似结核病疾病的可能病因。准确的菌种鉴定至关重要，以便针对由多种NTM菌种引起的疾病进行适当治疗。
