Chronic Idiopathic Inflammatory Bowel Diseases of the Horse

Abstract

A review of reported cases of inflammatory bowel diseases (IBDs) of horses for which no etiology was identified included cases of granulomatous enteritis (GE), multisystemic eosinophilic epitheliotropic disease (MEED), lymphocytic-plasmacytic enterocolitis (LPE), and idiopathic eosinophilic enterocolitis (EC). The terms EC and MEED were both used to describe a disease in horses characterized by infiltration of intestine and extraintestinal tissues with eosinophils. We use EC to describe IBD characterized by only intestinal infiltration by eosinophils. Horses with GE, MEED, or LPE are usually examined because of weight loss and depression, but horses with EC are usually examined because of signs of abdominal pain. Typically, horses with IBD have low concentrations of serumal proteins, especially albumin, and fail to adequately absorb glucose or xylose. Antemortem diagnosis of IBD can only be made by histologic examination of affected intestine. In some cases, antemortem diagnosis is made from histologic examination of rectal mucosa obtained by biopsy. Suspected causes of IBD in the horse include abnormal immune response to bacterial, viral, parasitic, or dietary antigens. Most horses with IBD do not survive, but horses with EC are more likely than those with LPE, MEED, or GE to respond to treatment. Successful treatments of horses with IBD include resection of grossly affected intestine and administration of corticosteroids.Key words: Eosinophilic enterocolitis; Granulomatous enteritis; Lymphocytic-plasmacytic enterocolitis; Multisystemic eosinophilic epitheliotropic disease.C hronic inflammatory bowel diseases (IBDs) are associated with dysfunction of the gastrointestinal tract due to infiltration of the mucosa and submucosa with populations of eosinophils, plasma cells, lymphocytes, basophils, or macrophages. 1,2 Clinical signs of IBD in the horse include weight loss, dependent edema, and lethargy and are usually associated with protein-losing enteropathy and malabsorption of nutrients, including glucose. Affected horses may have diarrhea or signs of abdominal pain. Signalment, clinical signs, clinicopathologic findings, and postmortem lesions may be highly characteristic of some types of IBD in the horse, but, in general, clinical and gross pathologic features of these diseases are similar, and a final morphologic diagnosis is based on histologic examination. When an etiologic diagnosis of IBD has been reported, mycobacterial 3-12 or parasitic infections, 13,14 or toxins 15 have been identified. The purpose of this report is to describe distinguishing features and discuss possible etiologies of the idiopathic IBDs and to discuss treatment of affected horses. Granulomatous Enteritis (GE)This idiopathic condition was 1st reported in 1974 by Cimprich, 7 who noted the histologic similarity between this disease and Crohn's disease in humans. In our review of the reports of idiopathic GE, we found detailed descriptions of 47 affected horses. 6,7,9,[16][17][18][19][20][21][22][23][24][25] Of these, 32 were Standardbr...

Idiopathic Eosinophilic Pneumonia with Associated Pulmonary Vasculitis in Horse: A Case Series

“…[3][4][5][6][7] Eosinophilic infiltrates of equine lungs are observed during parasitic infections or allergic condition 8,9 but eosinophilic pneumonia with vasculitis, which are not associated with parasitic infection and without the evidence of involvement of other organs have not been previously reported in horses. In the present study, we describe the gross and microscopic lesions of idiopathic eosinophilic pneumonia with associated vasculitis in 11 horses.…”

Intestinal biopsies for investigating and managing inflammatory bowel disease in horses

“…This finding was mirrored by a review of the evidence by Schumacher and others (2000), which found that the diagnosis was supported by rectal biopsy in approximately 50 per cent of cases of granulomatous enteritis and MEED. However, a diagnosis of lymphocytic-plasmacytic enteritis or eosinophilic enterocolitis was unlikely to be supported by rectal biopsy (Lindberg and others 1996, Schumacher and others 2000). A rectal biopsy is a useful procedure, but relies on the rectal mucosa having a similar cell infiltration and pathology as the grossly affected intestine, which will only occur in a proportion of cases.…”

“…The key to differentiating this condition from the other causes of IBD is that this disease is multisystemic, so most cases will also present with clinical signs related to other body systems. In previous reports, all horses with MEED have presented with weight loss, approximately 63 per cent had diarrhoea, 63 per cent had dermatological changes and just 4 per cent presented with colic (Schumacher and others 2000). Other clinical signs may include ulceration of the tongue and mouth, nasal discharge due to respiratory involvement, evidence of pancreatitis or lymphadenopathy (Fig 8).…”

Idiopathic eosinophilic enteritis in a pet goat

“…Occasionally it is seen in cattle and cats (Griffin and Meunier 1990, Ramirez and others 2012). It can present with various clinical symptoms, varying from acute colic to weight loss and depression in horses to chronic diarrhoea and weight loss in dairy cows (Pass and Bolton 1982, Cebra and others 1998, Schumacher and others 2000). Dogs and cats often present with vomiting, diarrhoea and weight loss (Griffin and Meunier 1990).…”

“…In some cases, the diagnosis is made on the basis of exclusion and trialled treatment with anthelmintics, dietary changes and antibiotics (Nelson and Couto 2009, Smith 2009). In other cases, intestinal biopsies are taken, either in vivo or at postmortem (Schumacher and others 2000, Kleinschmidt and others 2006). In horses, histology of these cases normally shows extensive infiltration of the lamina propria and submucosa with eosinophils, mast cells, macrophages and lymphocytes (Pass and Bolton 1982).…”