The diagnostic performance of point-of-care tests for serum amyloid A and C-reactive protein in lame sows.

Abstract

BACKGROUND: For acute phase proteins to be implemented in routine diagnostics for pig herds, a fast, reliable, and portable point-of-care test is required. Therefore, this study aimed to evaluate the diagnostic performance of two point-of-care tests on lame gestating sows. The two tests were the Cobas b101 CRP test for C-reactive protein and OmniChek-SAA for serum amyloid A. The reference test was an enzyme-linked immunosorbent assay (ELISA). RESULTS: The C-reactive protein point-of-care test had a concordance with the ELISA results of 0.12 (95% confidence limits: 0.12-0.23) and a mean difference of - 30.98 µg/mL (Limits of agreement: 27.45 and - 89.40 µg/mL), with a clear proportional bias. The serum amyloid A point-of-care test was only in agreement with the ELISA results in two out of 49 samples. The serum amyloid A test overestimated the serum amyloid A levels, whereas the C-reactive protein point-of-care test underestimated the C-reactive protein levels. CONCLUSIONS: Currently, the two point-of-care tests cannot be reliably used to determine acute phase protein levels in blood samples from lame gestating sows.