Geriatric Unit, Campus Bio-Medico University of Rome, Via Alvaro del Portillo 200, 00128, Rome, Italy.
Unit of Electronics for Sensor Systems, Faculty of Engineering, Campus Bio-Medico University of Rome, 00128, Rome, Italy.
J Transl Med. 2018 Jan 25;16(1):17. doi: 10.1186/s12967-018-1393-y.
Dipstick test is widely used to support the diagnosis of urinary tract infections (UTI). It is effective in ruling out UTI, but urine culture is needed for diagnosis confirmation. In this study we compared the accuracy of voltammetric analysis (VA) with that of DT to detect UTI (diagnosed using urine culture), and its usefulness as a second-stage test in people with positive DT.
142 patients were enrolled with no exclusion criteria. VA was performed using the BIONOTE device. Partial Least Square Discrimination Analysis was used to predict UTI based on VA data; diagnostic performance was evaluated using sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively), positive and negative likelihood ratios (LR), accuracy, diagnostic odds ratio (DOR).
Mean age was 76.6 years (SD 12.6), 57% were male. VA had a better overall performance respect to DT in detecting UTI with accuracy 81.7% vs 75.9%, specificity 90.8% vs 82.5%, PPV 75% vs 61.4%, positive LR 6.68 vs 3.5, DOR 17.7 vs 7.47; sensibility, NPV and negative LR of the two tests were similar. VA had an accuracy of 82.4% in discriminating bacterial from fungal infections. When added as a second-stage test, VA identified 9 of the 17 false positive patients, with a net specificity of 91.7%, sensitivity 54%, PPV 75% and NPV 81%.
VA is a quick and easy method that may be used as a second stage after DT to reduce the number of urine culture and of inappropriate antibiotic prescriptions.
尿试纸检测（DT）被广泛用于支持尿路感染（UTI）的诊断。它在排除 UTI 方面非常有效，但需要尿液培养来确诊。本研究比较了伏安分析（VA）与 DT 检测 UTI（通过尿液培养诊断）的准确性，以及其在 DT 阳性患者中作为二线检测的用途。
共纳入 142 名患者，无排除标准。使用 BIONOTE 设备进行 VA。采用偏最小二乘判别分析（PLS-DA）根据 VA 数据预测 UTI；采用灵敏度、特异性、阳性预测值（PPV）和阴性预测值（NPV）、阳性和阴性似然比（LR）、准确性、诊断比值比（DOR）评估诊断性能。
患者平均年龄 76.6 岁（标准差 12.6），57%为男性。VA 在检测 UTI 方面的整体性能优于 DT，准确性为 81.7%比 75.9%，特异性为 90.8%比 82.5%，PPV 为 75%比 61.4%，阳性 LR 为 6.68 比 3.5，DOR 为 17.7 比 7.47；两种检测方法的敏感性、NPV 和阴性 LR 相似。VA 区分细菌和真菌感染的准确性为 82.4%。作为二线检测方法添加后，VA 可识别 17 名假阳性患者中的 9 名，特异性为 91.7%，灵敏度为 54%，PPV 为 75%，NPV 为 81%。
VA 是一种快速简便的方法，可作为 DT 后的二线检测方法，以减少尿液培养和不适当抗生素处方的数量。
