Patients with acute renal failure often have a negative energy balance, which promotes metabolic changes predisposing to complications. The objective of this study was to evaluate laboratory parameters of 30 dogs with severe acute renal failure, to assess their relationship with the possibility of developing acute pancreatitis due to the negative energy balance, and to correlate these findings with the degree of renal failure. Serum concentrations of urea, creatinine, beta-hydroxybutyrate, triglycerides, amylase, total lipase, and canine pancreatic lipase were compared between healthy dogs and dogs with severe acute renal failure. A greater serum concentration of beta-hydroxybutyrate and greater activity of pancreatic enzymes, particularly canine pancreatic lipase, as well as a stronger correlation between the latter and serum creatinine concentrations, were related to the occurrence of acute pancreatitis in patients with severe acute renal failure. A greater degree of renal failure implied a greater predisposition to acute pancreatitis.