Evaluation of Disease Spectrum in Hospitalized Cats with Hyperlipasemia: Pancreatitis Alone Is Rare, Hyperlipasemia without Suspected Pancreatitis Is Common

Histological evidence of pancreatitis is commonly found in necropsy studies in cats. A clinical diagnosis of pancreatitis is challenging due to nonspecific clinical signs, a lack of diagnostic lipase cutoffs, and frequent presence of multiple diseases. It is still unknown how often pancreatitis alone is found in sick cats and how often clinicopathological evidence of pancreatitis in sick cats does not lead to a clinical diagnosis of pancreatitis. Our aims were to evaluate the extent of comorbidities in cats with suspected pancreatitis, evaluate how often sick cats with hyperlipasemia are diagnosed only with non-pancreatic diseases, and compare their clinical findings. Medical records of 563 client-owned hospitalized cats with available lipase activity measurement (LIPC Roche) > 30 U/L (RI, 6–26) were searched and medical diagnoses recorded and grouped by organ system. Clinicopathological findings were compared between cats with pancreatitis alone (PA), pancreatitis with concurrent disease (PD), and no suspected pancreatitis (NP). We found that PA was present in 33 (6%) cats, 159 cats (28%) were in the PD group, and 371 cats (66%) had no suspected pancreatitis (NP). Clinical, laboratory, and ultrasonographic findings did not differ between PA and PD cats. Lipase activities did not differ between the three groups. The most common disease categories in PD and NP cats were gastrointestinal, hepatobiliary, renal/urinary, and endocrine, and renal/urinary, gastrointestinal, cardiac, and musculoskeletal, respectively. We conclude that cats are rarely hospitalized because of suspected pancreatitis alone, and PA cats did not differ clinically from PD cats. Hyperlipasemia in sick cats without a diagnosis of pancreatitis may be due to a reactive pancreatopathy or preexisting chronic pancreatitis.