外周血中性粒细胞CD64及血清降钙素原对儿童社区获得细菌性肺炎的诊断价值

Diagnostic value of neutrophil CD64 and PCT in the children with community acquired pneumonia

目的探讨外周血中性粒细胞CD64表达及血清降钙素原(PCT)在儿童社区获得性肺炎(CAP)中的诊断价值.方法选取三亚市人民医院儿科收治的CAP患儿162例,依据病原体不同分为细菌性肺炎组(78例)、支原体肺炎组(39例)和病毒性肺炎组(45例).另选取同期健康体检儿童作为对照组.其中社区获得细菌性肺炎患儿依据入院病情严重程度分为轻症组(61例)和重症组(17例).采用流式细胞术检测外周血中性粒细胞CD64表达水平,化学发光法检测血清PCT水平.应用ROC曲线分析中性粒细胞CD64表达及血清PCT对社区获得细菌性肺炎的诊断价值.结果社区获得细菌性肺炎组治疗前中性粒细胞CD64表达水平(8.82±3.38vs.2.24±0.73,2.40±0.93,2.36±0.78)及血清PCT水平(ng/mL:6.15±1.41 vs.0.13±0.04,0.32±0.13,0.60±0.27)均明显高于对照组、病毒性肺炎组和支原体肺炎组(P<0.01).细菌性肺炎患儿治疗后CD64表达(2.68±1.05 vs.8.82±3.38)及血清PCT水平(ng/mL:0.20±0.04 vs.6.15±1.41)均明显低于治疗前(P<0.01).重症社区获得性细菌性肺炎患儿中性粒细胞CD64表达(10.40±4.35 vs.7.58±2.56)及血清PCT水平(ng/mL:9.25-±2.17 vs.4.60±1.13)均明显高于轻症社区获得性细菌性肺炎患儿(P<0.01).受试者工作特征(ROC)曲线分析显示,中性粒细胞CD64表达及血清PCT水平诊断细菌性肺炎的最佳截断值分别为3.20、1.81 ng/mL,两项联合检测诊断细菌性肺炎的曲线下面积(AUC=0.941,95%CI0.883~0.990)最大,其敏感度和特异度为95.4%和89.2%.Pearson相关分析显示,细菌性肺炎患儿中性粒细胞CD64与血清PCT呈正相关(r=0.729,P<0.01).结论外周血中性粒细胞中CD64及血清PCT两项联合检测有助于提高社区获得细菌性肺炎的诊断价值,并可作为判断CAP患儿病情严重程度的实验室指标.

Objective To explore the diagnostic value of neutrophil CD64 and procalcitonin(PCT)in the children with community acquired pneumonia(CAP).Methods 162 children with CAP admitted to Sanya People's Hospital were divided into bacterial pneumonia group(78 cases),mycoplasma pneumonia group(39 cases)and viral pneumonia group(45 cases).Children with community acquired bacterial pneumonia were divided into mild group(61 cases)and severe group(17 cases)according to the severity of admission.Flow cytometry was used to detect CD64 expression in peripheral blood neutrophils and chemiluminescence were used to detect PCT level.The diagnostic value of neutrophil CD64 and PCT levels in community acquired bacterial pneumonia were analyzed by ROC curve.Results Before treatment,the levels of CD64(8.82±3.38 vs.2.24±0.73,2.40±0.93,2.36±0.78)and PCT(ng/mL:6.15±1.41 vs.0.13±0.04,0.32±0.13,0.60±0.27)in bacterial pneumonia group were significantly higher than those in control group,viral pneumonia group and mycoplasma pneumonia group(P<0.01).After treatment,the levels of CD64(2.68±1.05 vs.8.82±3.38)and PCT(ng/mL:0.20±0.04 vs.6.15±1.41)in children with bacterial pneumonia were significantly lower than those before treatment(P<0.01).The levels of CD64(10.40±4.35 vs.7.58±2.56)and PCT(ng/mL:9.25±2.17 vs.4.60±1.13)in the children with severe bacterial pneumonia were significantly higher than those in the children with mild bacterial pneumonia(P<0.01).ROC curve analysis showed that the best cut-off values of CD64 and PCT for the diagnosis of bacterial pneumonia were 3.20 ng/mL and 1.81 ng/mL,respectively.The AUC(0.941,95%CI 0.883-0.990)of two combined diagnosis of bacterial pneumonia was the highest,with the sensitivity and specificity of 95.4%and 89.2%,respectively.Pearson correlation analysis showed that CD64 was positively correlated with PCT in the children with bacterial pneumonia(r=0.729,P<0.01).Conclusion The combined detection of CD64 and PCT is helpful to improve the diagnostic value of community acquired bacterial pneumonia and can be used as a laboratory index to judge the severity of CAP in children.