Intestinal crypt lesions associated with protein-losing enteropathy in thedog

Six dogs were diagnosed with protein-losing enteropathy (PLE). There was no evidence of inappropriate inflammatory infiltrates or lymphangiectasia in multiple mucosal biopsies of the small intestine of 4 of the dogs. The 5th and 6th dogs had obvious lymphangiectasia and a moderate infiltrate of infl ammatory cells in the intestinal mucose. All 6 dogs had a large number of d ilated intestinal crypts that were filled with mucus, sloughed epithelial c ells, and/or inflammatory cells. Whether PLE occurs in these dogs because o f protein lost from the dilated crypts into the intestinal lumen or whether the dilated crypts are a mucosal reaction due to another undetermined lesi on that is responsible for alimentary tract protein loss is unknown. Howeve r, when large numbers of dilated intestinal crypts are present, they appear to be associated with PLE even if there are no other remarkable lesions in the intestinal mucosa.