Proliferative Enteropathy
Basic Information 
Clinical Presentation
Physical Exam Findings
• Poor body condition and rough hair coat. Affected foals are often smaller than herdmates but may have a “potbellied” appearance.
• Fever is not consistently present.
• Variable tachycardia and tachypnea
• Ventral edema (caused by hypoproteinemia) is very common.
• Diarrhea may be present but is not universally observed.
• Gastric reflux is not a characteristic feature.
• Concurrent respiratory signs or dermatitis are occasionally seen because of debilitation.
Etiology and Pathophysiology
• L. intracellularis is an intracellular gram-negative rod. It has long been known as the cause of a similar syndrome in pigs. It is shed in the feces of infected animals, but the duration of time it remains infectious in the environment and the source of exposure for affected horses are not known. Exposure to pigs is not required for equine disease.
• The organism invades the crypt cells in the ileum and stimulates mitotic division, resulting in hyperplasia.
• Eventually, marked mucosal thickening and loss of intestinal villi occur, limiting intestinal absorptive capacity and resulting in weight loss and hypoproteinemia.
• With more severe disease, lesions may involve the remainder of the small intestine and occasionally the colon.
