Serum protein profiling of 100 cats with inflammatory bowel disease and lymphoma

Inflammatory bowel disease (IBD) and lymphoma are common in middle-aged to older cats, associated with chronic vomiting, weight loss, and diarrhea, included in the chronic enteropathy (CE) disorder. In cats, hypoalbuminemia in CE is considered infrequent, but specific investigations about protein profile in these patients have been not published . The aim of this study was to evaluate serum protein profiling in cats with IBD and lymphoma, and to compare it with clinical symptoms, endoscopic assessments and histopathological diagnoses. FCEAI clinical index score, CBC, serum biochemical profile and urinalysis were evaluated in 100 cats affected by IBD and lymphoma. Endoscopy of upper and lower gastrointestinal tract was performed and a severity score from 0 to 3 was assigned based on WSAVA guidelines. Histopathological diagnosis was based on WSAVA guidelines. Total serum protein, serum protein agarose gel electrophoresis, and albumin-globulin ratio (A/G) were evaluated at time of diagnosis. Cats ranged from 1 to 17 years old (10 median), 46% were females and 93% were European shorthair. The histologic diagnosis was IBD (66%) and lymphoma (34%). The most common symptoms were vomiting (70%), weight loss (67%) and diarrhea (37%). Mean FCEAI score was 9.4 ! 2.59. Mean serum total protein was 6.01 ! 0.99 g/dL. Low total protein (5.04 ! 0.63 g/dL) occurred in 41% of cats and only 10% had hypoalbuminemia. Beta globulins were decreased in 70% of cats, and gamma globulins were increased in 75%. A/G ratio was significantly higher in cats with hypoproteinemia (1.1 ! 0.3) compared to non-hypoproteinemic cats (0.9 ! 0.1). No statistical differences between protein profile and symptoms, FCEAI, gastrointestinal tract concerned, endoscopic score, type and severity of histologic pattern were found. Despite the hypoproteinemia was a relatively frequent finding in this work, a correlation with the clinical variables was not established. In addition, the clinical severity, the endoscopic and histological grading was not related to protein profile. Dysproteinemia with low beta globulin and high gamma globulin were the most common alterations. In hypoproteinemic cats A/G was higher than in non-hypoproteinemic cats. The decrease of beta globulin could be due to malnutrition but also to iron metabolism modifications occurring in chronic inflammatory disease, with reduction of transferrin and ferritin. Hypergammaglobulinemia is reported in human medicine as a common feature of IBD associated to extraintestinal manifestation. No data so far are available for the prevalence and clinical significance in cats.