Evaluation of a point‐of‐care test for canine C‐reactive protein

Abstract

In veterinary medicine, there is increasing interest in measuring C-reactive protein (CRP) as a tool for diagnosis and monitoring of inflammatory diseases. Reported CRP concentrations for healthy dogs have ranged from 0 to 8.9 mg/L. The aims of this study were to evaluate a canine-specific point-of-care (POC) lateral flow immunoassay for qualitative CRP measurement in healthy and diseased dogs and to compare results with those obtained by a quantitative ELISA. Blood samples from 73 client-owned dogs were available for testing: 16 healthy dogs and 57 dogs with a variety of infectious, inflammatory, or neoplastic diseases. CRP was measured in heparinized whole blood samples and serum with the TECO medical Dog CRP-visual POC test. A red line develops in the POC device if CRP is ≥ 5 mg/L, and results are scored as negative or positive. An ELISA validated previously for canine serum was used as the reference method. For all dogs, serum CRP concentrations measured by the ELISA ranged from 0.1 to ≥ 350 mg/L (median = 38 mg/L). Percentages of the CRP POC test results that agreed with the ELISA results were 98.6% for whole blood and 97.3% for serum samples. For serum samples, sensitivity of the POC test was 96.4% and specificity was 81.3%. For whole blood, sensitivity was 94.7% and specificity was 93.8%. The POC test had very good agreement with the ELISA test and had high sensitivity and specificity; therefore, it can be used as a qualitative test to screen for increases in CRP concentrations.