Porcine proliferative enteropathy by Lawsonia intracellularis and coinfection with Trichuris suis and Balantidium coli in a pig in Uruguay

Abstract

Porcine proliferative enteropathy (PPE) is an economically important, transmissible infectious disease of worldwide dis­tribution caused by Lawsonia intracellularis. The objective of this report is to describe a case of PPE caused by L. intracel­lularis in coinfection with Trichuris suis and Balantidium coli in Uruguay. The disease was diagnosed in October 2015 in a herd of 130 crossbred grower pigs up to 3 months of age. The cumulative incidence was 14% (18/130) and a lethality rate 83% (15/18). Affected animals presented profuse diarrhea, ill thrift and weakness, with progression to death after a clinical course of 10 days. At necropsy of one pig, the terminal segment of the ileum, cecum and colon showed thickening of the mucosa and irregular folds in a cerebriform pattern. In the cecum and prox­imal colon, there was also a diffuse fibrinonecrotic membrane attached to the mucosa with embedded specimens of Trichuris suis. Microscopic lesions were characterized by crypt and gland hyperplasia with branching and depletion of goblet cells in the ileum and cecum. Multiple areas of superficial necrosis and ul­ceration were recognized with numerous protozoans morpho­logically resembling Balantidium coli trophozoites adhered to the necrotic surface of the cecum. Lawsonia intracellularis was identified intralesionally by Warthin-Starry stain and immuno­histochemistry. Lawsonia intracellularis should be considered a differential etiologic diagnosis for diarrhea and enteropathy in swine in Uruguay.