Retrospective study of the diagnostic utility of Spec fPLin the assessment of 274 sick cats

BACKGROUND: Serum feline pancreatic lipase immunoreactivity (fPL) commonly is used in the assessment of sick cats suspected to have pancreatitis but its diagnostic utility is debated. OBJECTIVES: To evaluate the diagnostic utility of the Spec fPL test and selected serum biochemistry tests in the diagnosis of pancreatitis in cats. ANIMALS: Two hundred seventy‐four client‐owned cats presented to a university teaching hospital in the United Kingdom, from April 2013 to May 2017, in which Spec fPL was measured. METHODS: Cats were classified into 1 of 4 groups based on clinical signs (all cats), ultrasonographic findings (all cats) and histopathological or cytological assessment of the pancreas where available (9 cats) regardless of Spec fPL concentration. The groups were (a) definite pancreatitis (n = 9), (b) probable pancreatitis (n = 49), (c) possible pancreatitis (n = 139), and (d) unlikely pancreatitis (n = 77). Spec fPL and selected serum biochemistry test results were compared among groups. RESULTS: Serum fPL concentrations >5.3 μg/L were classified as positive and concentrations <3.5 μg/L were classified as negative. There was a significantly (P = .03) lower proportion of false‐positive results (cats unlikely to have pancreatitis, n = 77, with a positive fPL, n = 8, 10%) than false‐negative results (cats with definite or probable pancreatitis, n = 58, with a negative fPL result, n = 14, 24%). None of the selected biochemical tests were helpful diagnostically. CONCLUSION AND CLINICAL IMPORTANCE: A positive Spec fPL result indicates that pancreatitis is a probable diagnosis, but the test cannot be used to rule the diagnosis out.