Comparison of a full-spectrum multi-analyte clinical analyser with six reference instruments using canine and feline blood samples

In this study, we report the characterisation of a novel centrifugation and spectrum-integrated veterinary clinical analyser, the AmiShield^TM, which has been developed for the multiplex measurement of biochemical, electrolyte and immunoassay parameters in a point-of-care testing environment. The aims of this study were to evaluate the analytical performance of the AmiShield^TM and to compare it with six reference instruments using clinical blood samples. Two hundred and four canine and 120 feline blood samples collected from veterinary teaching hospitals were analysed in parallel using the AmiShield and appropriate reference instruments. All results were evaluated separately for canine and feline specimens. The instrument’s analytical performance was evaluated initially for short- and long-term precision, bias, and observed total error using quality control material. This was followed by comparison of clinical specimens on the AmiShield analyser in parallel with the Vitros and Hitachi for biochemical parameters, VetScan and SNAPshot for total bile acids, and VetLyte and Biolyte for electrolytes. Overall, the AmiShield analyser’s performance met the standards of the American Society for Veterinary Clinical Pathology for total allowable error for most analytes, and can be considered suitable for use in veterinary clinical practices. Using canine samples, excellent correlation coefficients (r ≧ 0.92) were identified for 14 analytes of various categories including glucose, total protein, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total bilirubin, amylase, blood urea nitrogen, creatinine, phosphorus, Na⁺, K⁺, Cl^– and total bile acid, while good correlations (0.91 ≧ r ≧ 0.80) were recorded for albumin (r = 0.91). Bland-Altman difference plots also showed agreement (greater than 95% within Limits of Agreement) for glucose, total protein, albumin, alanine aminotransferase, alkaline phosphatase, total bilirubin, amylase, blood urea nitrogen, creatinine, Na⁺, K⁺, Cl^– and total bile acid between AmiShield and the reference instruments. However, aspartate aminotransferase and phosphorus exhibited higher outliers, implying potential problems associated with matrix interferences such as lipemic samples, which warrant further study. This study demonstrates that the AmiShield compares favourably with standard reference instruments, and the new device generated data of high quality for most analytes in clinical canine and feline samples. The capability of reliably measuring multi-category analytes in one device using minute amounts (170 μl) of whole blood and short turn-around times (< 15 min) underlines the high potential of the device as a good alternative in-house diagnostic application.