结核抗体检测对活动性肺结核的诊断价值评价

目的 评价结核抗体检测对活动性肺结核的诊断价值。方法 收集2016年8月至2017年8月在重庆市公共卫生医疗救治中心结核科住院的495例活动性肺结核患者(观察组)和158例非结核呼吸道疾病患者(对照组),均为综合患者的临床表现、胸部影像、痰细菌病原学检测或诊断性抗结核药物治疗有效等资料临床确诊后进行血清学诊断。分析血清MTB免疫球蛋白G(immunoglobulin G,IgG)、免疫球蛋白M(immunoglobulin M,IgM)、脂阿拉伯甘露聚糖(lipoarabinomannan,LAM),以及相对分子质量16000(以下采用“16kD”表示)和相对分子质量38000(以下采用“38kD”表示)的蛋白抗体的检测资料,以及单独及联合检测不同结核抗原(LAM、38kD和16kD)的结果,评价两组患者结核抗体检测的敏感度、特异度、阳性预测值、阴性预测值,以及对活动性肺结核的诊断效能。结果 495例观察组患者血清结核抗体检测阳性率[68.7%(340/495)]明显高于158例对照组患者[34.8%(55/158)],差异有统计学意义(χ ²=57.50,P<0.01);菌阴肺结核患者血清结核抗体检测阳性率[64.0%(210/328)]明显低于菌阳肺结核患者[77.8%(130/167)],差异有统计学意义(χ ²=9.83,P<0.01)。观察组340例结核抗体阳性患者中,LAM、38kD、IgG抗体联合检测同时均阳性的患者最多[61.8%(210/340)];对照组55例结核抗体阳性患者中,单一IgG抗体阳性最高[67.3%(37/55)]。以临床诊断为标准,血清结核抗体对活动性肺结核的诊断敏感度、特异度、阳性预测值和阴性预测值、总符合率、约登指数分别为68.7%(340/495)、65.2%(103/158)、86.1%(340/395)和39.9%(103/258)、67.8%(443/653)、0.34。 结论 血清结核抗体检测活动性肺结核患者具有较高的阳性率和敏感度,对诊断活动性肺结核具有一定的辅助价值,其中菌阳肺结核患者的检测阳性率高于菌阴肺结核,LAM、38kD和IgG联合检测可提高活动性肺结核的诊断阳性率。

Evaluation of the serodiagnostic value by using tuberculosis antibody test in diagnosis of active pulmonary tuberculosis

Objective To evaluate the serodiagnostic value with tuberculosis (TB) antibody test in diagnosis of active pulmonary tuberculosis (PTB).Methods The clinical data and the results of serum Mycobacterium tuberculosis (MTB) antibody test based on IgG, IgM, LAM, 16kD, 38kD were collected from 495 patients with active PTB (experimental group) and 158 patients with non-tuberculosis respiratory diseases (control group), who hospitalized at Chongqing Public Health Medical Center during August 2016 to August 2017. Serodiagnosis was commenced in those patients after active PTB was confirmed by the comprehensive measures, including clinical manifestations, chest imaging, sputum bacteriological results or diagnostic anti-TB treatment responses. The sensitivity, specificity, positive predictive value and negative predictive value of the serum-tuberculosis antibody test in diagnosis of active PTB were evaluated.Results Out of 495 cases with active PTB, 340 cases showed positive sera TB antibody response (positive rate 68.7%); whereas, 55 out of 158cases with non-tuberculosis respiratory diseases revealed positive serum TB antibody detection test (positive rate 34.8%). The positive rate of serum TB antibody test in the experimental group was significantly higher than that in the control group (χ ²=57.50, P<0.01). The positive rate of serum TB antibody test (64.0%, 210/328) in the patients with bacteriologically negative pulmonary TB was lower than that (77.8%, 130/167) in the patients with bacteriologically positive PTB, and this difference was statistically significant (χ ²=9.83, P<0.01). In the experimental group, among 340 cases with positive TB antibody test results, 210 cases (61.8%, 210/340) were found to be positive with anti-LAM, 38kD and IgG antibodies at the same. The sensitivity, specificity, positive predictive value and negative predictive value of the serum TB antibody detection test based on IgG, IgM, LAM, 16kD, 38kD was 68.7% (340/495), 65.2% (103/158), 86.1% (340/395) and 39.9% (103/258) respectively; the Youden index and the overall consistent rate was 0.34 and 67.8% (443/653) respectively. Conclusion This study suggests that the serum TB antibody test has excellent accuracy and auxiliary diagnosis value in the diagnosis of patients with active PTB. The sensitivity of serum TB antibody test among the bacteriologically positive PTB patients is higher than that in the bacteriologically negative patients. The diagnostic sensitivity of PTB may be improved by the united detection of anti-LAM, 38kD and IgG antibodies.