超氧化物歧化酶及常用生物标志物检测对继发性肺结核并发呼吸衰竭的诊断价值

The Values of SOD and Common Biomarkers in Diagnosing Secondary Pulmonary Tuberculosis Complicated with Respiratory Failure

目的分析超氧化物歧化酶（SOD）及临床常用生物标志物用于诊断继发性肺结核并发呼吸衰竭的应用价值。方法收集首都医科大学附属北京胸科医院2015年3～12月确诊为继发性肺结核的143例患者的外周血标本，其中，继发性肺结核患者（肺结核组）71例，继发性肺结核并发呼吸衰竭患者（呼吸衰竭组）72例。检测并分析研究对象外周血标本SOD、超敏C反应蛋白（HCRP）、红细胞沉降率（ESR）及N末端-前脑钠肽（NT-proBNP）水平。结果呼吸衰竭组的SOD水平为（524．16±225．97）mg／ml，低于肺结核组的（725．34±325．63）mg／ml；HCRP水平为（68．51±43．6）mg／L，高于肺结核组的（56．07±39．56）mg／L；ESR水平为（50．05±29．03）mm／1h，高于肺结核组的（37．13±27．58）mm／1h；NT-proBNP水平为（882．19±182．36）ng／L，高于肺结核组的（360．26±73．99）ng／L；差异均有统计学意义（t值分别为3．90、1．78、2．69、22．78，P值均〈0．05）。经logistic多因素分析显示，肺结核患者的SOD水平≥300mg／ml时，发生呼吸衰竭的风险是SOD〈300mg／ml时的89％（OR=0．89；95％CI=0．76～0．92）；肺结核患者的NT-proBNP水平≥80ng／L时发生呼吸衰竭的风险是NT-proBNP〈80ng／L时的1．21倍（OR=1．21；95％CI=1．12～1．28）。SOD、ESR、HCPR、NT-proBNP在预测肺结核患者是否易发生呼吸衰竭的受试者工作特征曲线分析显示SOD的曲线下面积（AUC）值最高为0．862，敏感度为73．2％，特异度为93．1％，临界值（cut—off值）为478．51mg／ml。NT-proBNP的AUC值为0．764，敏感度72．5％，特异度82．7%，cut—off值为340．20ng/L。结论继发性肺结核患者血浆中SOD及NT-proBNP水平对患者是否并发呼吸衰竭具有良好的辅助诊断价值。

Objective To analyze the performance of superoxide dismutase （SOD） and the common clinical biomarkers for diagnosis of secondary pulmonary tuberculosis complicated with respiratory failure. Methods The peripheral blood of 143 cases with secondary pulmonary tuberculosis in Beijing Chest Hospital, Capital Medical University between March 2015 and December 2015 were collected in this study. Among the included patients, there were 71 cases with pulmonary tuberculosis （defined as pulmonary tuberculosis group） and 72 cases with secondary pulmonary tuberculosis complicated with respiratory failure （defined as respiratory failure group）. The levels of concentrations of SOD, hypersensitive C reactive protein （HCRP）, erythrocyte sedimentation rate （ESR） and NT-proBNP were tested. Results The level of SOD was 524.16 ± 225.97 mg/ml in respiratory failure group, which was lower than that in the pulmonary tuberculosis group （725.34 ± 325.63 mg/ml）. The level of HCRP was 68.51 ± 43.6 mg/L in respiratory failure group, which was higher compared with the pulmonary tuberculosis group （56.07 ± 39.56 mg/L）. The ESR was 50.05 ± 29.03 mrn/l h in respiratory failure group, higher than that in pulmonary tuberculosis group （37.13 ± 27.58 mm/1 h）. The level of NT-proBNP was 882.19 ± 182.36 ng/L in respiratory failure group, which was higher than that in the in pulmonary tuberculosis group （360.26 ± 73.99 ng/L）. The differences in the levels of SOD, HCRP, ESR and NT-proBNP were statistically significant （t=3.90, 1.78, 2.69 and 22.78; Ps〈0.05）. The logistic multivariate analysis showed that the risk of respiratory failure in pulmonary tuberculosis patients with a SOD level of ≥300 mg/ml was 89% compared with patients with a SOD level of 〈300 mg/ml （0R=0.89; 95% CI=0.76-0.92）; the risk in patients with a NT-proBNP level of ≥ 80 ng/L was 1.21 times of patients with a NT-proBNP of〈80 ng/L （OR=1.21; 95% CI=1.12-1.28）. Receiver operating characteristic curves （ROC） analysis showed that area under curve （AUC） of SOD in diagnosing respiratory failure in pulmonary tuberculosis patients was 0.862, followed by NT-proBNP, HCRP and ESR. the sensitivity of SOD was 73.2% and specificity was 93.1%; the cut-off value was 478.51 mg/ml. AUC of NT-proBNP was 0.764, the sensitivity of NT-proBNP was 72.5% and specificity was 82.7%, and the cut-off value was 340.20 pg/ml. Conclusion The plasma levels of SOD and NT-proBNP have good clinical values in monitoring the occurrence of respiratory failure in secondary pulmonary tuberculosis patients.