Canine Pancreatic-Specific Lipase Concentrations in Clinically Healthy Dogs and Dogs with Naturally Occurring Hyperadrenocorticism

BACKGROUND: Specificity of canine pancreatic lipase immunoreactivity (cPLI) assays in dogs with hyperadrenocorticism (HAC) is unknown. HYPOTHESIS: Results of cPLI assays differ for clinically healthy dogs and dogs with HAC. ANIMALS: Seventeen healthy dogs and 20 dogs with HAC diagnosed by ACTH stimulation test results without evidence of clinical pancreatitis. METHODS: Dogs were enrolled between December 2009 and November 2010. Serum cPLI concentrations were determined by quantitative (Spec cPL test, SPEC) and semiquantitative (SNAP cPL test, SNAP) assays. Results were categorized as normal, equivocal, or abnormal (SPEC) or negative or positive (SNAP). Associations between group and cPLI were assessed using Fisher's exact test or the Mann-Whitney U-test. Spearman rank correlation coefficients (ρ) were determined for SNAP and SPEC results. Significance was set at P < .05. RESULTS: Spec cPL test concentrations were significantly (P < .001) higher in dogs with HAC (491.1 μg/L) than in healthy dogs (75.2 μg/L), with more abnormal SPEC results in HAC dogs (P < .001). There were more (P = .002) positive SNAP results in dogs with HAC (55%) than in healthy dogs (6%). SNAP and SPEC results were highly correlated (ρ = 0.85; P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with HAC had higher SPEC concentrations and more positive SNAP results than clinically healthy dogs with normal ACTH stimulation test results. Specificity of SPEC and SNAP assays in HAC dogs without clinical pancreatitis were 65 and 45%, respectively. Pending further study, SNAP and SPEC results should be interpreted cautiously in dogs with HAC to avoid false diagnosis of concurrent pancreatitis.