Interest is growing in measurement of novel biomarkers for the diagnosis of acute kidney injury. Multiplex assays may provide a rapid and cost-effective way of measurement; however, sparse information is published regarding their use in dogs. We aimed to validate a commercial magnetic bead–based assay for 5 biomarkers: clusterin (Clus), cystatin C (CysC), kidney injury molecule 1 (KIM-1), monocyte chemoattractant protein 1 (MCP-1), and neutrophil gelatinase–associated lipocalin (NGAL). Intra- and inter-assay imprecision, linearity under dilution (LUD), spike recovery (S-R), and hemoglobin interference were evaluated using serum from healthy and diseased dogs. Additionally, the effect of sample type (serum vs. plasma) was investigated. All values for Clus and MCP-1 were outside the assay’s measurable range. Intra- and inter-assay precision were acceptable for NGAL (CVs 8.8% and 13.2%, respectively). Regression analysis of LUD and S-R indicated good linearity for CysC and NGAL. Hemolysis did not affect measurement of any biomarker. Measured concentrations of CysC (p = 0.018) and NGAL (p = 0.015) were significantly lower in sodium citrate plasma compared to serum. We conclude that this magnetic bead–based assay is precise and accurate for NGAL measurement in canine serum. Inappropriate standards for MCP-1 and Clus, and poor accuracy for KIM-1 measurement, suggest that this assay cannot reliably quantify those biomarkers in canine blood. Measurements of CysC in canine blood using this assay must be interpreted with caution given inter-assay imprecision.

对用于诊断急性肾损伤的新型生物标志物的测量越来越感兴趣。多重分析可以提供一种快速且经济高效的测量方法；但是，关于它们在狗中的使用的信息很少。我们旨在验证一种基于商业磁珠的测定方法，用于5种生物标记：簇蛋白（Clus），胱抑素C（CysC），肾损伤分子1（KIM-1），单核细胞趋化蛋白1（MCP-1）和中性白细胞明胶酶–相关脂质运载蛋白（NGAL）。使用健康和患病犬的血清评估了测定内和测定间的不准确性，稀释度下的线性（LUD），加标回收率（SR）和血红蛋白干扰。此外，还研究了样品类型（血清与血浆）的影响。Clus和MCP-1的所有值均超出测定的可测量范围。NGAL的测定内和测定间精密度是可以接受的（CV分别为8.8％和13.2％）。LUD和SR的回归分析表明CysC和NGAL具有良好的线性。溶血不影响任何生物标志物的测量。测出的CysC浓度（与血清相比，柠檬酸钠血浆中的p = 0.018）和NGAL（p = 0.015）显着降低。我们得出的结论是，这种基于磁珠的测定对于犬血清中的NGAL测量是精确而准确的。MCP-1和Clus的标准不当，以及KIM-1测量的准确性差，表明该测定法无法可靠地定量犬血中的那些生物标志物。鉴于测定间的不准确性，必须谨慎解释使用此测定法对犬血中CysC的测量。