LAUSR

Abstract Background Oxidative stress is considered a pathomechanism of acute pancreatitis (AP), but no studies have extensively characterized oxidant status in dogs with naturally‐occurring AP. Hypothesis or Objectives Evaluate measures of oxidant status in dogs with AP and explore whether these measures correlate with AP severity. Animals Fifteen dogs with AP and 9 control dogs. Methods Prospective, controlled observational study. Plasma reactive metabolite (RM) concentrations, antioxidant potential (AOP), and urinary F2 isoprostane concentrations were measured in AP dogs and healthy controls. Severity of AP was assessed by length of hospitalization and 3 disease severity indices: canine acute pancreatitis severity (CAPS), modified canine activity index (M‐CAI), and the acute patient physiologic and laboratory evaluation score (APPLEfull). Results Reactive metabolite (RM) concentrations (median, 65 relative fluorescent units [RFU]/μL; range, 20‐331 RFU/μL) and RM:AOP (median, 7; range, 4‐109) were higher in AP dogs than healthy controls (median RM, 25 RFU/μL; range, 16‐41 RFU/μL; median RM:AOP, 4; range, 2‐7; P < .001 for both comparisons). Reactive metabolite (r S = 0.603, P = .08) and RM:AOP (r S = 0.491, P = .06) were not correlated with the duration of hospitalization or disease severity indices evaluated. However, disease severity indices did not predict mortality in our study. Normalized urine 2,3‐dinor‐8‐iso‐prostaglandin F2α concentrations were correlated with C‐reactive protein (CRP; r S = 0.491, P = .03), canine specific pancreatic lipase (Spec cPL; r S = 0.746, P = .002), and CAPS (r S = 0.603, P = .02). Conclusions and Clinical Importance Oxidant status is altered in dogs with naturally occurring AP, but the clinical relevance of this finding is unknown.