尿路结石患者尿白细胞酯酶对尿细菌培养的预测价值

Predictive value of urinary leukocyte esterase to urine bacteria culture of patients with lithangiuria

目的评估尿白细胞酯酶对尿路结石患者是否合并尿路感染的诊断价值。方法 308例尿路结石患者及127例非尿路结石可疑尿路感染患者为研究对象。研究尿液标本均为无菌采集中段尿,进行尿细菌培养、白细胞酯酶干化学法检测。比较两样本间白细胞酯酶诊断的敏感性、特异性。结果白细胞酯酶诊断尿路结石患者合并尿路感染的敏感性为90.0%,特异性为29.5%,阳性预测值为19.8%,阴性预测值为93.8%;诊断非尿路结石尿路感染的敏感性为93.8%,特异性为32.3%,阳性预测值为59.2%,阴性预测值为83.3%。白细胞酯酶诊断尿路结石患者合并尿路感染的敏感性与非尿路结石尿路感染差异无统计学意义(P=0.499);特异性与非尿路结石尿路感染差异无统计学意义(P=0.647);阳性预测值明显低于非尿路结石尿路感染(P=0.000);阴性预测值与非尿路结石尿路感染差异无统计学意义(P=0.205)。结论与非尿路结石患者比较,尿白细胞酯酶对诊断尿路结石患者合并尿路感染的阳性预测值明显降低。

[ Abstract ] Objective To appraise the diagnostic value of urinary leukocyte esterase in the test of lithangiuria combined with urinary tract infection. Methods There were 308 cases of lithangiuria and 127 cases without lithangiuria but suspected with urinary tract infection were selected as objects of study. The urine specimens were all collected as asepsis midstream urine, and send for urine bacteria culture and dry chemical method test for leukocyte esterase. The specificities and the sensibilities of leukocyte esterase were compared. Results In the cases of lithangiuria combined with urinary tract infection, the sensibility of leukocyte esterase test was 90.0%, the specificity was 29.5%, the positive predictive value was 19.8% and the negative predictive value was 93.8%. While in the cases of suspected urinary tract infection without lithangiuria, the sensibility of leukocyte esterase test was 93.8%, the specificity was 32.3%, the positive predictive value was 59.2% and the negative predictive value was 83.3%. The difference of the sensibility of leukocyte esterase test between the two kinds of cases was not statistically significant （P=0.499）. The difference of specificity had no statistical significance （P=0.647）. The positive predictive value of the former cases was obviously higher than that of the later cases （P=0.000）. The difference of the negative predictive value had no statistical significance （P=0.205）. Coneittsion Compared with the cases of no lithangiuria, leukocyte esterase test for the positive predictive value of lithangiuria combined with urinary tract infection cases is much lower.