目的 探讨脓肿分枝杆菌复合群(MABC)对克拉霉素的耐药机制,为MABC肺病诊治提供依据.方法 对广州市胸科医院冻存的191株龟-脓肿分枝杆菌复合群进行hsp65、rpoB、ITS多靶位基因菌种鉴定,确定为MABC的菌株进行克拉霉素最低抑菌浓度(MIC)药敏,延长培养时间至14 d,记录3、7、10、14 d的MIC值,观察MABC对克拉霉素诱导耐药情况,并对耐药相关基因rrl和erm(41)进行测序,研究克拉霉素耐药表型和基因型的关系.结果 191株龟-脓肿分枝杆菌复合群经多靶位基因法鉴定出2株龟分枝杆菌,189株MABC,其中111株脓肿分枝杆菌,78株马赛分枝杆菌.111株脓肿分枝杆菌中,克拉霉素获得性耐药1株,获得性耐药率0.9％;克拉霉素诱导耐药78株,诱导耐药率70.3％;总耐药株79株,总耐药率71.2％;78株马赛分枝杆菌无诱导耐药,克拉霉素获得性耐药5株,获得性耐药率6.4％;总耐药株5株,总耐药率为6.4％;脓肿分枝杆菌和马赛分枝杆菌总耐药率和获得性耐药率差异均有统计学意义(P＜0.05).6株克拉霉素获得性耐药菌株中,rrl突变的菌株5株,突变率为83.3％;所有的脓肿分枝杆菌erm(41)序列完整,所有的马赛分枝杆菌erm(41)序列有短缺;111株脓肿分枝杆菌,T28序列型菌株84株、C28序列型菌株27株.78株马赛分枝杆菌皆为T28序列型.结论 MABC为我国较为常见的非结核分枝杆菌,耐药率高,可用药物有限,治疗困难,主要菌种为脓肿分枝杆菌,根本的原因在于克拉霉素诱导耐药,准确的菌种鉴定、可靠的药敏试验对指导MABC肺病的临床治疗有重要意义.

Objective:To evaluate the clinical value of pathogen detection of pulmonary tuberculosis using bronchial lavage fluid as sample.Methods:The data of laboratory information system from Guangzhou Chest Hospital between January and December, 2019 were used; and the results of auramine O fluorescent stain smear and mycobacterial isolation of sputum and bronchial lavage fluid were comparatively analyzed.Results:The positive rates of 115 bronchial lavage fluid smears or 307 sandwich cup collection smears of bronchial lavage fluid were significantly lower than those of the sputum smears ( P<0.001 and P=0.049). The positive rates of Mycobacteria isolated from bronchial lavage fluid and sputum with the MGIT 960 system from the 882 patients were 37.53% and 33.90%, respectively. 89 patients who were negative in sputum culture were positive in the culture of bronchial lavage fluid, accounting for 10.09%, with a statistical difference ( χ2=353.555, P<0.001). Conclusion:Isolating mycobacterial from bronchial lavage fluid is an important method for the diagnosis of pulmonary tuberculosis, but the value of stain smear test is small.