Inflammatory bowel disease in humans, 4 pets, and horses

Abstract

Inflammatory bowel disease (IBD) is a group of chronic inflammatory conditions of the gastrointestinal tract. In humans, two major types exist: Crohn’s disease and ulcerative colitis. Similarly, also pets can suffer from IBD having predominantly lymphocytic-plasmacytic enteritis/colitis, but also eosinophilic enteritis/colitis is common. Accumulating evidence suggest the induction of an inappropriate inflammatory response to intestinal microbes in a genetically susceptible host as well as a dysregulation of the intestinal microbiota. Symptoms of IBD are similar in humans and pets and may include diarrhea, vomiting, weight loss, anemia, as well as extraintestinal manifestations affecting the eye (uveitis), skin (rash), and joints (arthritis). Diagnosis of IBD requires a number of tests with endoscopy being the best tool to determine IBD. Biopsies of the mucosa are taken for differential diagnosis of IBD. As the pathogenesis of IBD is still unresolved, but implicates genetic factors, microbes, diet, and an aberrant immune response, so far treatment regiments only aim to control the disease activity by immunosuppressive medications like glucocorticoids. However, novel treatment options are underway that aim to reset the microbiota and showing promising efficacy. There are thus many similarities in the clinical picture of IBD affecting humans, horses, and dogs, which not only give us great insight in the pathogenesis of IBD, but enable the pursuit of novel treatment options.