宏基因组二代测序对下呼吸道感染分枝杆菌的诊断和鉴别诊断价值

The Diagnostic and Differential Diagnostic Value of Metagenomic Next-Generation Sequencing for Mycobacterial Infections in the Lower Respiratory Tract

摘要: 目的：探讨利用宏基因组二代测序技术(mNGS)，对下呼吸道感染病人的肺泡灌洗液(BALF)进行检测，对分枝杆菌诊断及鉴别诊断的应用价值。方法：回顾性分析2019年7月至2024年8月在青岛大学附属医院呼吸与危重症医学科因下呼吸道感染住院的509例病人临床资料和BALF样本分枝杆菌检出情况。结果：在509例BALF样本中，抗酸染色阳性31例，阳性率为6.09%；mNGS检测出分枝杆菌92例，阳性率为18.07%。两者检测结果具有显著差异(χ² = 12.98, P < 0.05)。在92例分枝杆菌中，结核分枝杆菌复合群(MTBC) 55例，占59.78%；非结核分枝杆菌(NTM) 37例，占40.22%，其中鸟–胞分枝杆菌复合群(MAC) 31例、堪萨斯分枝杆菌1例、慢生黄分枝杆菌2例和脓肿分枝杆菌3例。非结核分枝杆菌中，MAC占83.78% (31/37)。mNGS检测显示，男、女患者BALF样本中MTBC的检出差异具有统计学意义(χ² = 4.6761, P < 0.05)，而不同年龄组中分枝杆菌的检出差异无统计学意义。在MTBC和MAC阳性患者中，合并感染类型存在差异，差异具有统计学意义。结论：mNGS可以提供对分枝杆菌的快速诊断和鉴别诊断，有助于临床及时、精准、有效的治疗。

Abstract: Objective: To explore the application value of diagnosis and differential diagnosis for the detection of mycobacteria in the bronchoalveolar lavage fluid (BALF) of patients with lower respiratory tract infections using metagenomic next-generation sequencing (mNGS). Methods: A retrospective analysis was conducted on the clinical data and BALF mycobacteria detection results of 509 patients with lower respiratory tract infections who were admitted to the Department of Respiratory and Critical Care Medicine at The Affiliated Hospital of Qingdao University from July 2019 to August 2024. Results: Among the 509 BALF samples, 31 were positive for acid-fast staining, resulting in a positivity rate of 6.09%. The mNGS identified 92 cases of mycobacteria, with a positivity rate of 18.07%. There was a significant difference between the two detection methods (χ² = 12.98, P < 0.05). Among the 92 identified mycobacteria, 55 cases were of the Mycobacterium tuberculosis complex (MTBC), accounting for 59.78%, while 37 cases were non-tuberculous mycobacteria (NTM), accounting for 40.22%. Within the NTM group, 31 cases were Mycobacterium avium complex (MAC), 1 case was Mycobacterium kansasii, 2 cases were slow-growing yellow mycobacteria, and 3 cases were Mycobacterium abscessus; MAC comprised 83.78% (31/37) of the NTM cases. The mNGS results indicated a statistically significant difference in the detection of MTBC between male and female patients (χ² = 4.6761, P < 0.05), while there was no statistically significant difference in the detection of mycobacteria among different age groups. Furthermore, the types of co-infections found in MTBC and MAC-positive patients exhibited significant differences. Conclusion: mNGS can provide a rapid and accurate method for the diagnosis and differential diagnosis of mycobacteria, facilitating timely and effective clinical treatment.