降钙素原、白细胞及C反应蛋白对尿路感染患者的诊断效能

Value of procalcitonin, white blood cell, and C-reactive protein in diagnosis of urinary tract infection

目的探索降钙素原(PCT)及C反应蛋白(CRP)、白细胞计数(WBC)对尿路感染(UTI)的诊断效能。方法收集2013年1月至2014年12月在重庆市黔江中心医院就诊、符合临床诊断、影像学检查、实验室检查,且清洁中段尿培养为阳性的尿路感染者189例为病例组,同时选择无泌尿系或其他部位感染的健康体检者149例为对照组。上述的研究对象入组后,在首诊时收集血样检测PCT、CRP和WBC的含量。结果病例组患者的PCT、CRP和WBC的含量分别为(19.36±34.69) ng/mL、(10.04±5.11) mg/L、(29.24±43.24)×109/L;均明显高于对照组的(0.59±1.81) ng/mL、(7.58±3.45) mg/L、(5.49±0.50)×109/L,差异均具有统计学意义(P<0.05);PCT的最大诊断效能的截断值为0.5 ng/mL (灵敏度:97.89%,特异度:95.30%);对三个指标的诊断效能绘制受试者工作曲线(ROC),PCT、CRP和WBC的曲线下的面积(AUC)分别为0.930、0.789、0.657,PCT的曲线下面积最大。PCT、CRP和WBC的灵敏度及特异度分别为97.89、95.30和86.24、85.23和68.25、69.13,PCT的灵敏度及特异度为三者中最高。结论 PCT是一种预测UTI有效的生物学指标,对临床医生首次诊断UTI及实施医疗策略有较大帮助。

Objective To evaluate the diagnostic value of procalcitonin(PCT),C-reactive protein(CRP),and white blood cell(WBC)count in patients with urinary tract infection(UTI).Methods From Qianjiang Central Hospital of Chongqing between January,2013 and December,2014,189 patients positive in bacterial culture of mid-stream urine and met the criteria of UTI(clinical diagnosis,imaging examination,laboratory examination)were included in this study as case group,and 149 healthy individuals without urinary tract or other infection were selected as control group.Serum PCT,CRP,and WBC count were checked at initial hospital visit.Results PCT,CRP,and WBC count in the case group was(19.36±34.69)ng/m L,(10.04±5.11)mg/L,(29.24±43.24)×109/L,respectively,significantly higher than(0.59±1.81)ng/mL,(7.58±3.45)mg/L,(5.49±0.50)×109/L in the control group(P<0.05).The cut-off value for maximum diagnostic performance of PCT was 0.5 ng/mL,with a sensitivity of 97.89%and a specificity of 95.30%.PCT had a significantly greater area under the curve(AUC)than CRP and WBC count,and the AUC was 0.930,0.789 and 0.657 for PCT,CRP and WBC,respectively.The sensitivity for diagnosis of UTI was 97.89,86.24 and 68.25 for PCT,CRP,and WBC,respectively,and the specificity was 95.30,85.23,and 69.13 for PCT,CRP,and WBC,respectively.The sensitivity and specificity of PCT were the highest among the three variables.Conclusion PCT is a valuable marker for predicting UTI.It is helpful for clinicians to diagnose UTI at initial hospital visit and implement medical strategies.