Plasma and urinary trypsinogen activation peptide in healthy dogs, dogs with pancreatitis and dogs with other systemic diseases

Objective To determine the specificity and sensitivity of plasma and urinar y trypsinogen activation peptide (TAP) concentrations in diagnosing pancrea titis in dogs. Design Retrospective analysis of clinical cases. Procedure Dogs were classified into three groups: healthy animals, dogs wit h confirmed pancreatitis and dogs with nonpancreatic disease, which clinica lly or biochemically resembled pancreatitis. This last group was further su bdivided into dogs with renal and those with nonrenal disease. The plasma a nd urinary TAP concentration was determined by a competitive enzyme immunoa ssay. Clinical cases additionally had serum trypsin-Iike immunoreactivity c oncentration measured, as well as radiography and ultrasound of the abdomen and further diagnostic procedures. Nonparametric analysis of variance (Kru skal-Wallis test) was performed using Statistix 4.0 program. Results There was a wide range of urinary TAP concentration in healthy dogs (mean 52.30 nmol/L, standard deviation 55.25) that made interpretation of urinary TAP concentrations difficult in the other groups. There was a narro w reference range for plasma TAP (mean 2.67 nmol/L, standard deviation 0.93 ). Plasma and urinary TAP concentrations, as well as urinary TAP to creatin ine ratio, were all increased in dogs that died with necrotising pancreatit is. Values were not increased in mild, interstitial pancreatitis. Increased plasma TAP concentrations were also present in dogs with severe renal dise ase. Conclusion Plasma TAP concentration is a good prognostic indicator in natur ally occurring pancreatitis in dogs. The failure of TAP to increase in mild pancreatitis, and the increase present in severe renal disease, suggests i ts measurement has limited application as a sole diagnostic tool for canine pancreatitis. Further investigations are required in order to explain the large variability of urinary TAP concentration and the presence of circulat ing TAP in healthy dogs.