Investigation of the Usefulness of Serum Amyloid A in Supporting the Diagnosis of Equine Proliferative Enteropathy

Abstract The objective of this study was to determine if serum amyloid A (SAA), a major acute-phase protein, could help support the diagnosis of equine proliferative enteropathy (EPE) caused by Lawsonia intracellularis infection in foals. Archived serum samples from 101 foals with enteric signs and hypoproteinemia were available for SAA testing. Based on immunodiagnostics for L. intracellularis, the foals were divided into EPE-suspect (67) and non–EPE-suspect cases (34). Serum amyloid A values ranged from 0 to 2,761 μg/mL (median 466 μg/mL) and from 0 to 2,555 μg/mL (median 192 μg/mL) for the EPE-suspect and the non–EPE-suspect cases, respectively. Although SAA can be measured patient-side and help determine the severity of the underlying inflammatory condition, SAA was unable to consistently support the diagnosis of EPE in hypoproteinemic foals with enteric signs.