Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA.
Department of Pathology, Los Angeles County + University of Southern California (LAC+USC) Medical Center, Los Angeles, CA.
J Appl Lab Med. 2020 Jul 1;5(4):724-731. doi: 10.1093/jalm/jfaa011.
Urinalysis (UA) reflex testing approaches, which offer potential for savings in labor and result turnaround time, may rely on the performance of a chemical UA screen to determine which urine samples need microscopic UA and/or urine culture. We correlated chemical UA, microscopic UA, and urine culture results to determine the performance of chemical UA as a screening tool for reflex testing approaches.
Consecutive UA results for 9127 tests (simultaneous chemical UA and microscopic UA) were retrospectively reviewed and correlated. Urine culture results were also correlated for 3127 samples that had urine culture ordered within 24 h of UA. Positivity criteria for each UA method were predefined.
Chemical UA yielded the following performance specifications for predicting microscopic findings: 93.0% sensitivity, 56.9% specificity, 64.7% positive predictive value, 90.5% negative predictive value. 3.2% of samples were negative by chemical UA but positive by microscopic UA. Of the samples with urine culture results available, 6.3% were negative by chemical UA but had clinically-significant positive urine cultures.
Reflex testing of microscopic UA and/or urine culture dependent from chemical UA results provides a feasible opportunity to reduce unnecessary testing.
尿液分析 (UA) 反射测试方法具有节省劳动力和缩短结果周转时间的潜力，可能依赖于化学 UA 筛查来确定哪些尿液样本需要进行微观 UA 和/或尿液培养。我们将化学 UA、微观 UA 和尿液培养结果进行关联，以确定化学 UA 作为反射测试方法的筛查工具的性能。
回顾性分析了 9127 例连续 UA 检测结果（同时进行化学 UA 和微观 UA），并进行了相关性分析。还对 3127 例在 UA 检测后 24 小时内进行尿液培养的样本进行了尿液培养结果的相关性分析。为每种 UA 方法预先设定了阳性标准。
化学 UA 对预测微观结果具有以下性能指标：93.0%的灵敏度、56.9%的特异性、64.7%的阳性预测值、90.5%的阴性预测值。3.2%的样本化学 UA 检测结果为阴性，但微观 UA 检测结果为阳性。在有尿液培养结果的样本中，6.3%的样本化学 UA 检测结果为阴性，但尿液培养结果具有临床意义上的阳性。
根据化学 UA 结果进行微观 UA 和/或尿液培养的反射测试为减少不必要的检测提供了一个可行的机会。
