MTB特异性细胞免疫反应试剂盒检测活动性肺结核患者出现假阴性的危险因素分析

目的 探讨结核分枝杆菌特异性细胞免疫反应(QuantiFERON-TB Gold In-Tube,QFT-GIT)试剂盒检测活动性肺结核患者出现假阴性的相关影响因素。方法 收集2018年7—10月间于湖南省胸科医院住院并通过病史、临床症状、体征、影像学、细菌学、病理、诊断性治疗等手段单独或联合确诊的1287例活动性肺结核患者作为研究对象,根据纳入和排除标准最终纳入1072例。采用多因素logistic回归分析QFT-GIT检测活动性肺结核患者造成假阴性的独立危险因素。结果 1072例活动性肺结核患者QFT-GIT结果显示假阴性188例(17.5%),真阳性884例(82.5%)。QFT-GIT真阳性结果中40~岁与60~92岁年龄组的患者分别占32.1%(284/884)和23.0%(203/884),复治患者占18.3%(162/884),肺结核并发肺外结核的患者占11.0%(97/884),培养阴性患者占72.5%(641/884)、白蛋白<35g/L的患者占9.6%(85/884)、淋巴细胞计数<0.6×10 ⁹/L的患者占1.8%(16/884);QFT-GIT假阴性结果中40~岁与60~92岁年龄组的患者分别占36.7%(69/188)和38.8%(73/188)、复治患者占31.4%(59/188)、肺结核并发肺外结核的患者占20.7%(39/188)、培养阴性的患者占86.2%(162/188)、白蛋白<35g/L的患者占19.1%(36/188)、淋巴细胞计数<0.6×10 ⁹/L的患者占7.4%(14/188);差异均有统计学意义(χ ²值分别为31.819、16.085、13.574、16.651、14.072、18.109,P值均<0.05)。多因素logistic回归分析显示,40~岁年龄组(OR=1.972,95%CI=1.306~2.976,P=0.001)、60~92岁年龄组(OR=2.782,95%CI=1.832~4.224,P<0.001)、复治(OR=1.741,95%CI=1.174~2.581,P=0.006)、肺结核并发肺外结核(OR=2.043,95%CI=1.314~3.176,P=0.002)、痰培养阴性(OR=3.354,95%CI=2.066~5.446,P<0.001)、白蛋白<35g/L(OR=2.777,95%CI=1.721~4.481,P<0.001)、淋巴细胞计数<0.6×10 ⁹/L(OR=3.662,95%CI=1.679~7.987,P=0.001)为QFT-GIT假阴性的独立危险因素。结论 40~岁年龄组、复治、肺结核并发肺外结核、培养阴性、白蛋白<35g/L和淋巴细胞计数<0.6×10 ⁹/L是造成QFT-GIT检测活动性肺结核患者出现假阴性结果的独立危险因素。

Analysis of risk factors for false-negative results with QuantiFERON-TB Gold In-Tube in the diagnosis of active pulmonary tuberculosis

Objective To investigate the influence factors of false-negative results of QuantiFERON-TB Gold In-Tube (QFT-GIT) in active pulmonary tuberculosis patients. Methods A total of 1287 patients with active pulmonary disease admitted to Hunan Chest Hospital from July to October 2018 were collected as study subjects, they were diagnosed individually or jointly based on medical history, clinical symptoms, signs, imaging, bacteriology, pathology and diagnostic treatment; 1072 patients were finally included according to inclusion and exclusion criteria. Multivariate logistic regression analysis was used to analyze independent risk factors for the false negative results of QFT-GIT in patients with active pulmonary tuberculosis patients. Results All the 1072 patients could be divided into 188 false-negative cases (17.5%) and 884 true positive cases (82.5%). Among the true positive cases, patients aged 40- and 60-92 years old were 32.1% (284/884) and 23.0% (203/884), respectively; 18.3% (162/884) were re-treated patients; 11.0% (97/884) were pulmonary tuberculosis with extra-pulmonary tuberculosis; 72.5% (641/884) were with negative mycobacterial cultures; 9.6% (85/884) with albumin <35 g/L; lymphocyte count <0.6×10 ⁹/L in 1.8% (16/884). Among the false-negative cases, 36.7% (69/188) and 38.8% (73/188) were aged 40- and 60-92 years old, respectively; 31.4% (59/188) were re-treated patients; 20.7% (39/188) were with pulmonary tuberculosis and extra-pulmonary tuberculosis; 86.2% (162/188) were negative in mycobacterial cultures; 19.1% (36/188) with albumin <35 g/L; 7.4% (14/188) with lymphocyte count <0.6×10 ⁹/L. All the differences were statistically significant (χ ² values were 31.819, 16.085, 13.574, 16.651, 14.072, and 18.109, respectively; P<0.05). According to multivariate analysis, patients aged 40- years old (OR=1.972, 95%CI=1.306-2.976,P=0.001), 60-92 years old (OR=2.782, 95%CI=1.832-4.224,P<0.001), re-treated tuberculosis (OR=1.741, 95%CI=1.174-2.581,P=0.006), pulmonary tuberculosis and extra-pulmonary tuberculosis (OR=2.043, 95%CI=1.314-3.176,P=0.002), negative mycobacterial culture (OR=3.354,95%CI=2.066-5.446,P<0.001), albumin <35 g/L (OR=2.777, 95%CI=1.721-4.481,P<0.001), lymphocyte count <0.6×10 ⁹/L (OR=3.662, 95%CI=1.679-7.987,P=0.001) were independent risk factors for false-negative result of QFT-GIT. Conclusion Aged 40- years old, re-treated tuberculosis, pulmonary tuberculosis with extra-pulmonary tuberculosis, culture-negative, albumin <35 g/L, and lymphocyte count <0.6×10 ⁹/L are independent risk factors for false-negative results of QFT-GIT in patients with active pulmonary tuberculosis.