Ferlizza Enea, Dondi Francesco, Andreani Giulia, Bucci Diego, Archer Joy, Isani Gloria
1 Department of Veterinary Medical Sciences, University of Bologna, Ozzano, Italy.
2 Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
J Feline Med Surg. 2017 Aug;19(8):860-868. doi: 10.1177/1098612X16664112. Epub 2016 Aug 23.
Objectives The aims of this study were to validate a semi-automated high-resolution electrophoretic technique to quantify urinary albumin in healthy and diseased cats, and to evaluate its diagnostic performance in cases of proteinuria and renal diseases. Methods Urine samples were collected from 88 cats (healthy; chronic kidney disease [CKD]; lower urinary tract disease [LUTD]; non-urinary tract diseases [OTHER]). Urine samples were routinely analysed and high-resolution electrophoresis (HRE) was performed. Within-assay and between-assay variability, linearity, accuracy, recovery and the lowest detectable and quantifiable bands were calculated. Receiver operating curve (ROC) analysis was also performed. Results All coefficients of variation were <10%, percentage recovery was between 97% and 109% with a high linearity (r = 0.99). HRE allowed the visualisation of a faint band of albumin and a diffused band between alpha and beta zones in healthy cats, while profiles from diseased cats were variable. Albumin (mg/dl) and urine albumin:creatinine ratio (UAC) were significantly ( P <0.05) different between healthy and diseased cats. After ROC analysis, UAC values of 0.035 and 0.074 had a high sensitivity and high specificity, respectively, to classify proteinuria and identify borderline proteinuric cats. Moreover, a UAC of 0.017 had a high sensitivity in distinguishing between healthy and diseased cats. However, UAC was not able to distinguish between renal (CKD) and non-renal diseases (LUTD/OTHER), probably owing to the pathophysiology of CKD in cats, which is characterised by low-grade proteinuria and less glomerular involvement than in dogs. Conclusions and relevance HRE is an accurate and precise method that could be used to measure albuminuria in cats. UAC was useful to correctly classify proteinuria and to discriminate between healthy and diseased cats. HRE might also provide additional information on urine proteins with a profile of all proteins (albumin and globulins) to aid clinicians in the diagnosis of diseases characterised by proteinuria.
目的 本研究的目的是验证一种半自动高分辨率电泳技术，用于定量健康和患病猫的尿白蛋白，并评估其在蛋白尿和肾脏疾病病例中的诊断性能。方法 从88只猫（健康；慢性肾脏病[CKD]；下尿路疾病[LUTD]；非尿路疾病[OTHER]）收集尿液样本。对尿液样本进行常规分析并进行高分辨率电泳（HRE）。计算批内和批间变异性、线性、准确性、回收率以及最低可检测和可定量条带。还进行了受试者工作特征曲线（ROC）分析。结果 所有变异系数均<10%，回收率在97%至109%之间，具有高线性（r = 0.99）。HRE可使健康猫中出现一条微弱的白蛋白条带以及α和β区之间的弥散条带，而患病猫的图谱则有所不同。健康猫和患病猫之间的白蛋白（mg/dl）和尿白蛋白：肌酐比值（UAC）存在显著差异（P <0.05）。经过ROC分析，UAC值分别为0.035和0.074时，对蛋白尿分类和识别临界蛋白尿猫具有高敏感性和高特异性。此外，UAC为0.017在区分健康猫和患病猫方面具有高敏感性。然而，UAC无法区分肾脏疾病（CKD）和非肾脏疾病（LUTD/OTHER），这可能是由于猫CKD的病理生理学特点，即与狗相比，其蛋白尿程度较低且肾小球受累较少。结论及相关性 HRE是一种准确且精确的方法，可用于测量猫的蛋白尿。UAC有助于正确分类蛋白尿并区分健康猫和患病猫。HRE还可能通过提供所有蛋白质（白蛋白和球蛋白）的图谱，为尿液蛋白质提供额外信息，以帮助临床医生诊断以蛋白尿为特征的疾病。
