CD64、CRP、PCT及NLR对儿童社区获得性肺炎的诊断价值

Diagnostic value of CD64,CRP,PCT and NLR in children with community acquired pneumonia

目的探讨中性粒细胞CD64、C反应蛋白(CRP)、降钙素原(PCT)及中性粒细胞与淋巴细胞比值(NLR)在儿童社区获得性肺炎(CAP)中的诊断价值。方法选取海口市人民医院收治的CAP患儿186例,依据病原体不同分为细菌性肺炎组(95例),支原体肺炎组(43例)和病毒性肺炎组(48例)。细菌性肺炎患儿依据入院病情严重程度分为轻症组(75例)和重症组(20例)。采用流式细胞术检测外周血中性粒细胞CD64的表达,同时检测CRP、PCT及NLR水平。应用ROC曲线分析CD64、CRP、PCT及NLR水平对细菌性肺炎的诊断价值。结果细菌性肺炎组治疗前CD64(8.85±3.40 vs 2.26±0.74,2.42±0.95,2.38±0.80)、CRP(38.62±8.50 vs 3.25±0.96,3.42±1.15,4.16±1.53,mg/L)、PCT(6.17±1.40 vs 0.15±0.03,0.34±0.12,0.62±0.28,ng/mL)及NLR(7.84±3.25 vs 2.05±0.96,1.37±0.62,2.48±1.16)水平均明显高于对照组、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(2.70±1.06 vs 8.85±3.40)、CRP(4.63±1.58 vs 38.62±8.50,mg/L)、PCT(0.21±0.06 vs 6.17±1.40,ng/mL)及NLR(2.28±1.07 vs 7.84±3.25)水平均明显低于治疗前(P<0.01)。重症细菌性肺炎患儿CD64(10.42±4.36 vs 7.60±2.58)、CRP(43.25±10.47 vs 34.85±8.16,mg/L)、PCT(9.26±2.18 vs 4.62±1.15,ng/mL)及NLR(9.75±4.12 vs 6.53±2.90)水平均明显高于轻症细菌性肺炎(P<0.01)。ROC曲线分析显示,CD64、CRP、PCT及NLR单项指标诊断细菌性肺炎的最佳截值分别为3.25、14.80 mg/L、1.83 ng/mL、4.37,四项联合诊断细菌性肺炎的AUC(0.948,95%CI:0.887~0.992)最大,其敏感度和特异度为96.2%和89.3%。Pearson相关分析显示,细菌性肺炎患儿CD64与CRP、PCT及NLR呈正相关(r=0.573、0.729、0.536,P<0.01),CRP与PCT及NLR呈正相关(r=0.602、0.497,P<0.01),PCT与NLR呈正相关(r=0.514,P<0.01)。结论CD64、CRP、PCT及NLR四项联合检测有助于提高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 investigate the diagnostic value of neutrophil CD64,C-reactive protein(CRP),procalcitonin(PCT)and neutrophil to lymphocyte ratio(NLR)in children with community acquired pneumonia(CAP).Methods 186 children with CAP admitted to Haikou People’s Hospital were divided into the bacterial pneumonia group(95 cases),the mycoplasma pneumonia group(43 cases)and the viral pneumonia group(48 cases).Children with bacterial pneumonia were divided into the mild group(75 cases)and the severe group(20 cases)according to the severity of admission.Flow cytometry was used to detect the expression of CD64 in peripheral blood neutrophils and the levels of CRP,PCT and NLR.The diagnostic value of CD64,CRP,PCT and NLR levels in bacterial pneumonia was analyzed by ROC curve.Results The levels of CD64(8.85±3.40 vs 2.26±0.74,2.42±0.95,2.38±0.80),CRP(38.62±8.50 vs 3.25±0.96,3.42±1.15,4.16±1.53,mg/L),PCT(6.17±1.40 vs 0.15±0.03,0.34±0.12,0.62±0.28,ng/mL)and NLR(7.84±3.25 vs 2.05±0.96,1.37±0.62,2.48±1.16)in the bacterial pneumonia group before treatment were significantly higher than those in the control group,the viral pneumonia group and the mycoplasma pneumonia group(P<0.01).The levels of CD64(2.70±1.06 vs 8.85±3.40),CRP(4.63±1.58 vs 38.62±8.50,mg/L),PCT(0.21±0.06 vs 6.17±1.40,ng/mL)and NLR(2.28±1.07 vs 7.84±3.25)in children with bacterial pneumonia after treatment were significantly lower than those before treatment(P<0.01).The levels of CD64(10.42±4.36 vs 7.60±2.58),CRP(43.25±10.47vs 34.85±8.16,mg/L),PCT(9.26±2.18 vs 4.62±1.15,ng/mL)and NLR(9.75±4.12 vs 6.53±2.90)in children with severe bacterial pneumonia were significantly higher than those in children with mild bacterial pneumonia(P<0.01).The best cut-off value of CD64,CRP,PCT and NLR for bacterial pneumonia was 3.25,14.80 mg/L,1.83 ng/mL and 4.37,respectively.The AUC(0.948,95%ci:0.887~0.992)of the four combined diagnosis of bacterial pneumonia was the highest,with the sensitivity and specificity of 96.2%and 89.3%,respectively.Pearson correlation analysis showed that CD64 was positively correlated with CRP,PCT and NLR(r=0.573,0.729,0.536,P<0.01),CRP was positively correlated with PCT and NLR(r=0.602,0.497,P<0.01),and PCT was positively correlated with NLR(r=0.514,P<0.01)in children with bacterial pneumonia.Conclusion The combined detection of CD64,CRP,PCT and NLR can improve the diagnostic value of bacterial pneumonia,and can be used as a laboratory index to judge the severity of CAP in children.