This study reported on the prevalence of pancreatitis in 115 cats at the time of necropsy, during which the entire pancreas was removed and the left and right portions and body of the pancreas were examined. Histopathologic changes of acute or chronic pancreatitis were noted and lesion scores were assigned. Of the 115 cats, 41 were considered to be healthy, 22 had a history of gastrointestinal disease, and 52 had extragastrointestinal disease (eg, nongastrointestinal-associated neoplasia). The overall prevalence of pancreatitis (acute or chronic) was 67%; 45% of healthy cats had evidence of pancreatitis at the time of necropsy. Chronic pancreatitis (60%) was more common than acute pancreatitis (18%). In many of the pancreases examined, evidence of both chronic and acute forms was noted. As a group, healthy cats always had the lowest lesion scores for both forms. In contrast, cats with gastrointestinal disease had higher scores for acute pancreatitis than cats with nongastrointestinal-associated illnesses. The highest scores for chronic pancreatitis were found in cats with extragastrointestinal disease. The left lobe of the pancreas had a significantly higher score for chronic pancreatitis when compared with the right lobe in cats with gastrointestinal disease. The chronic form was significantly more common in older cats and was characterized by a greater frequency of fibrosis than inflammation. The acute form was characterized by neutrophilic inflammation, interstitial edema, and necrosis of mesenteric fat.

COMMENTARY: Pancreatitis is notoriously difficult to diagnose in cats, and the authors of this study clearly found that it is underdiagnosed. Pancreatic biopsy is considered by many to be the gold standard for diagnosis in cats. On the basis of the findings in this study, cats with gastrointestinal-associated lesions have significantly more lesions in the left lobe, suggesting that in the absence of other clear-cut areas to sample, the left lobe may be the site of choice for biopsy.

Prevalence and histopathologic characteristics of pancreatitis in cats. DeCook HEV, Forman MA, Farver TB, Marks SL. VET PATHOL 44:39-49, 2007.