降钙素原、C反应蛋白在社区获得性肺炎细菌感染的诊断价值

Diagnosis value of serum procalcitonin and C-reactive protein in community-acquired pneumonia

目的探讨血清降钙素原(PCT)及C反应蛋白(CRP)在社区获得性肺炎(CAP)中的诊断价值。方法回顾性分析明确诊断为肺部疾病的患者122例,分为细菌感染组54例和非细菌感染组68例,并根据重症肺炎诊断标准,将细菌感染组分为重症肺炎18例,轻中症肺炎36例。记录并比较所有患者入院24 h内的血常规、PCT、CRP、病原学等指标,并描绘ROC曲线进行分析。结果 PCT及CRP在CAP患者中的水平高于非细菌感染的患者(t分别=3.62、7.25,P<0.05)。重症组的PCT和CRP水平明显高于轻中症组(t分别=2.37、2.65,P均<0.05)。ROC曲线分析显示,所有患者PCT和CRP的ROC曲线下面积分别为0.89和0.88,PCT和CRP诊断CAP细菌感染的最佳诊断阈值分别为0.09μg/L、29.27 mg/L。重症细菌感染组PCT和CRP的ROC曲线下面积分别为0.80和0.74,PCT和CRP诊断重症细菌感染的最佳诊断阈值分别为0.17μg/L、85.17 mg/L,此时PCT、CRP的灵敏度分别为88.89%、66.67%,特异度分别为66.65%、80.55%,PCT对重症细菌感染具有高度灵敏度,在重症细菌感染中的敏感性较CRP高,特异性未见明显优势。结论 CAP患者的PCT及CRP水平较非细菌感染肺疾病患者高;PCT联合CRP对诊断细菌性肺炎及重症细菌感染性肺炎具有更高的特异性,有助于提高诊断的准确性。

Objective To explore the diagnosis value of serum procalcitonin （PCT） and C-reactive protein （CRP） in community-acquired pneumonia （CAP）. Methods A total of 122 patients diagnosed as lung disease which of 54 patients with CAP and 68 patients with non-bacterial infection of lung disease were enrolled. According to the severe pneumonia diagnosis criteria,the bacterial infection group was divided into severe pneumonia and light and moderate pneumonia. Rou-tine bloods, PCT, CRP,etiology and other relevant indicators were recorded and compared. ROC curve were described and analyzed. Results The PCT and CRP in patients with CAP were significantly higher than those in patients with non-bac-terial infection（t=3.62, 7.25,P〈0.05）. The PCT and CRP in severe groups were significantly higher than those in the light and moderate groups （t=2.37,2.65,P〈0.05）. ROC curve analysis showed that the areas of PCT and CRP under the ROC curve in all patients were 0.89 and 0.88 respectively. The best diagnostic threshold of PCT and CRP were 0.09 μg/L and 29.27mg/L respectively. The areas of PCT and CRP under the ROC curve in patients with CAP were 0.80 and 0.74 respec-tively. The best diagnostic threshold of PCT and CRP were 0.17μg/L and 85.17mg/L respectively. At this point, the sensi-tivity of PCT and CRP were 88.89%and 66.67%, the specificity were 66.65%and 80.55%. PCT had high sensitivity to the severe bacterial infection. For severe bacterial infection, PCT had higher sensitivity than CRP while its specificity had no obvious difference. Conclusions PCT and CRP in patients with CAP were higher than those in patients with non-bacterial infection of pulmonary disease. Combined PCT with CRP has a higher specificity in diagnosis of bacterial pneumonia and severe bacterial infection, which is helpful to improve the accuracy of diagnosis.