Chronic inflammatory and non-inflammatory diseases of the gastrointestinal tract in cats: diagnostic advantages of full-thickness intestinal and extraintestinal biopsies

Abstract

An evaluation of histological findings in full-thickness biopsies from the gastrointestinal tract (GIT) and extraintestinal samples of 43 cats with chronic GIT disease signs was performed. In the majority of cases (46.5%) inflammatory bowel disease, ie, lymphocytic-plasmacytic enteritis/colitis (32.6%), eosinophilic gastroenterocolitis (11.6%) and mixed inflammatory infiltration (2.3%), was diagnosed. Furthermore, in four animals non-inflammatory mucosal band-shaped fibrosis (9.3%), and in 10 cats (23.3%) a diffuse lymphoma, was found. Six cats displayed only a gastritis (7.0%) or lymphangiectasia (7.0%), respectively. In two cats a mast cell tumour (4.7%) was diagnosed. In one cat no histopathological lesions were found. The availability of transmural biopsies from all segments of the intestine and the collection of extraintestinal samples, especially mesenteric lymph nodes, is especially helpful for diagnosing intestinal tumours such as lymphomas and tumours of mast cell origin.

Fig 1.

A mixed inflammatory infiltration with mainly neutrophilic granulocytes and few lymphocytes and plasma cells was observed in the colon of one cat. The mixed inflammation was accompanied by architectural distortion (indicated by arrows), eg, focal epithelial necrosis and atrophy of crypts. HE. Bar=200 μm.

Fig 2.

Band-shaped intestinal fibrosis of the ileal lamina propria mucosae without increased inflammatory infiltrate or other architectural changes. Fibrotic bands were mainly located at the border between crypts and villi (indicated by arrows). HE. Bar=100 μm.

Fig 3.

Transmural lymphangiectasia of the duodenal lamina propria and submucosa (arrows) without increased inflammatory cell infiltrate. HE. Bar=200 μm.