Medical Service, VA Connecticut Healthcare System, West Haven, CT 06516, USA.
Nephron Clin Pract. 2009;113(4):c281-5. doi: 10.1159/000235243. Epub 2009 Sep 3.
BACKGROUND/AIMS: Urinary tract infections (UTIs) are common in dialysis patients. The diagnostic accuracy of pyuria in this population has been incompletely evaluated and is the object of this study.
We assembled a historical cohort of male hemodialysis patients with urinalysis and urine microbiology data. Each matched pair of urinalysis and urine culture was considered as the unit of measurement. We evaluated the diagnostic performance and plotted receiver operating characteristic curves for different cutoff values of pyuria [>5, >10, >50, >100 white blood cells per high-power field (WBC/HPF)].
Of 134 patients, 97 had at least one matched urinalysis and urine culture, providing 224 pairs for analysis. The prevalence of pyuria was 65 and 51% using cutoff values of >5 or >10 WBC/HPF, respectively. The presence of pyuria (>5 WBC/HPF) had a sensitivity between 82 and 89% and specificity of between only 53 and 55%. The presence of nitrites on dipstick had high specificity (94%) but very poor sensitivity (14-20%). All other urinary indices had poor diagnostic performance in the identification of a positive urine culture.
In the absence of adequate specificity and positive predictive value in dialysis patients, urine culture should be obtained to guide further treatment.
背景/目的：尿路感染（UTIs）在透析患者中很常见。该人群中脓尿的诊断准确性尚未得到充分评估，这是本研究的目的。
我们组建了一个男性血液透析患者的历史队列，这些患者有尿液分析和尿液微生物学数据。每个尿液分析和尿液培养的匹配对都被视为测量单位。我们评估了不同脓尿[>5、>10、>50、>100 个高倍视野（WBC/HPF）白细胞]截断值的诊断性能，并绘制了受试者工作特征曲线。
在 134 名患者中，97 名至少有一次尿液分析和尿液培养相匹配，为分析提供了 224 对。使用>5 或>10 WBC/HPF 的截断值，脓尿的患病率分别为 65%和 51%。脓尿（>5 WBC/HPF）的存在具有 82%至 89%的敏感性和仅 53%至 55%的特异性。尿液试纸上的亚硝酸盐存在具有很高的特异性（94%），但敏感性很差（14-20%）。所有其他尿液指标在识别阳性尿液培养物方面的诊断性能都很差。
在透析患者中缺乏足够的特异性和阳性预测值的情况下，应进行尿液培养以指导进一步治疗。
