The importance of histologic parameters of lacteal involvement in cases of canine lymphoplasmacytic enteritis

The most frequent form of inflammatory bowel disease (IBD) in dogs is represented, histologically, by lymphoplasmacytic enteritis (LPE), a histological category, often associated with other morphologic alterations including lymphangiectasia (LE). However, literature data on this latter topic are quite scarce and have mostly been obtained in single reports or in small series. Currently, there are no objective pathologic parameters that indicate a cut-off value above which the lacteals’ diameter can be considered indicative of clinically significant LE. Thus, we evaluated some morphologic parameters of intestinal villi and lacteals in a large cohort of dogs, and correlated them with serum albumin and cholesterol values. We investigated 136 dogs (94 with LPE, and 42 with gastrointestinal problems different from IBD) and analyzed their clinical, laboratory (albumin and cholesterol values), endoscopic, and histologic variables. The LPE group showed significantly impaired clinical, laboratory, endoscopic, and histologic variables compared to control dogs. Affected dogs showed significant correlations between canine inflammatory bowel disease activity index (CIBDAI) scores and endoscopic and histologic variables. Moreover, the grade of hematologic changes were strongly related to the intestinal histologic variables, in particular those concerning villous and lacteals morphology. Dogs with LPE had intestinal histologic abnormalities (height, width, height/width ratio, calculated for both villi and lacteals), whose degree correlated with the severity of hypoalbuminemia and hypocholesterolemia. Evaluation of endoscopic and histologic variables in association to the clinical findings may reveal useful insights for the pathogenesis of LPE and, hopefully, might lead to more targeted therapeutic approaches.