血清降钙素原联合内毒素对肺结核合并肺部细菌感染早期诊断的意义

Combined Detection of Serum Procalcitonin and Endotoxin for Early Diagnosis of Pulmonary Tuberculosis Complicated by Bacterial Infection

目的探讨血清降钙素原(PCT)与内毒素(LSP)联合检测在肺结核患者合并肺部细菌感染早期诊断中的临床价值。方法收集56例肺结核合并肺部感染患者(研究组)及同期62例单纯性肺结核患者(对照组),比较2组患者的血清PCT、LSP、C-反应蛋白(CRP)水平,血沉(ESR),血白细胞(WBC)计数及胸部影像学检查结果,探讨血清PCT与LSP联合检测对肺结核患者并发肺部细菌感染早期诊断的特异性和敏感性。结果与对照组相比,研究组中PCT、LSP、ESR、CRP的水平均明显升高(均P<0.05)。研究组中PCT、LSP和胸部影像学检查阳性率分别为83.94%(47/56)、80.36%(45/56)和76.78%(43/56),明显高于对照组的27.42%(17/62)、22.58%(14/62)、19.35%(12/62),差异有统计学意义(均P<0.05);在最佳诊断截点处,行PCT联合LSP检测诊断肺结核患者合并肺部细菌感染的曲线下面积、特异度和灵敏度分别为0.937、93.79%和90.48%,均高于其他单项PCT、LSP、ESR、CRP检测,差异有统计学意义(P<0.05或P<0.01)。结论胸部影像学,血清PCT、LSP、CRP及ESR对肺结核合并肺部细菌感染诊断均有一定的价值,尤以PCT联合LSP灵敏度及特异度最高;对于肺结核患者,不论胸部影像学是否阳性,均应早期联合检测PCT及LSP,以提高早期诊断肺部感染的能力。

Objective To investigate the clinical value of combined detection of serum procalcitonin（PCT）and endotoxin（LSP）for early diagnosis of pulmonary tuberculosis complicated by bacterial infection.Methods Serum levels of PCT,LSP and C-reactive protein（CRP）,erythrocyte sedimentation rate（ESR）,white blood cell count（WBC）,and chest imaging results were compared between patients with pulmonary tuberculosis（control group,n=62）and patients with pulmonary tuberculosis complicated by bacterial infection（study group,n=56）.The specificity and sensitivity of the combined PCT and LPS detection for early diagnosis of pulmonary tuberculosis complicated by bacterial infection was investigated.Results The serum PCT,LSP and CRP levels and ESR in study group were higher than those in control group（P〈0.05）.Furthermore,the positive rates ofPCT,LSP and chest radiological examinations in study group（83.94%,80.36% and 76.78%,respectively）were higher than those in control group（27.42%,22.58% and 19.35%,respectively）（P〈0.05）.At the best diagnostic cut-off point,the area under the curve,sensitivity and specificity of the combined PCT and LPS detection for diagnosis of pulmonary tuberculosis complicated by bacterial infection were 0.937,93.79% and 90.48%,respectively,which were higher than those of PCT,LSP,ESR or CRP determination alone（P〈0.05 or P〈0.01）.Conclusion The chest radiography,serum PCT,LSP and CRP detection,and ESR determination are valuable for early diagnosis of pulmonary tuberculosis complicated by bacterial infection.Especially,the combined PCT and LSP detection has the highest sensitivity and specificity.Therefore,whether or not the chest radiography is positive in patients with pulmonary tuberculosis,combined detection of PCT and LSP should be performed to improve the ability of early diagnosis of pulmonary infection.