Segmental eosinophilic colitis: A review of 22 cases

Abstract

SummaryTwenty-two horses with colic, referred to the University of Liverpool Equine Hospital (1992-1998), were found at laparotomy to have a partial obstruction of the large colon caused by a segmental mural lesion located in the left dorsal colon. The decision to take the horses to surgery was based on rectal examination findings of secondary impaction and mural oedema of the large colon and turbid peritoneal fluid containing large numbers of neutrophils obtained by paracentesis. The affected segment of colon showed oedema and serosal changes varying from erythema to well-defined necrosis. These. pathological changes were considered to be sufficiently severe in 16 horses to merit partial resection of the left colon. Histology revealed varying degrees of mucosal necrosis, marked submucosal oedema and infiltration with large numbers of eosinophilic leucocytes. No cause was identified for the lesions. Sixteen of the 18 horses discharged from the hospital were alive 3 months to 7 years after surgery and have returned to their previous type of work and level of performance. The remaining 2 horses were subjected to euthanasia because of a recurrence of colic but no autopsy was performed.

Overview of Clinical Pathology and the Horse

“…These lesions tend to be progressive and ultimately will lead to fibrosis within the intestinal tract mediated by cytokines responsive to the eosinophilic infiltrates, such as transforming growth factor a. [34][35][36] Ultrasound and laparoscopic evaluation may be helpful, but biopsy is the mainstay of diagnosis. 68 Glucose tolerance tests may be used to document decreased intestinal absorption; values should increase after the administration of glucose if mucosal absorption is present (Box 1).…”

“…Hypereosinophilic syndromes are not uncommon in horses and involve the intestinal tract, skin, respiratory system, or all of these organs; but less than 20% of the literature reported cases exhibited eosinophilia. [34][35][36] …”

Intestinal biopsies for investigating and managing inflammatory bowel disease in horses

“…This condition has been described as circumferential mural bands (Perez Olmos and others 2006), idiopathic focal eosinophilic enteritis (Archer and others 2006, Proudman and Kipar 2006, Southwood and others 2000), idiopathic eosinophilic enteritis (Stanar and others 2002) and segmental eosinophilic colitis (Edwards and others 2000). It is presumed that these conditions are manifestations of the same condition, although there are differences noted between the syndrome described by Edwards and others (2000) and the lesions referred to as IFEE. The main difference was that segmental eosinophilic colitis affects the left dorsal colon (Edwards and others 2000), whereas IFEE predominately affects the jejunum (Archer and others 2006).…”

“…It is presumed that these conditions are manifestations of the same condition, although there are differences noted between the syndrome described by Edwards and others (2000) and the lesions referred to as IFEE. The main difference was that segmental eosinophilic colitis affects the left dorsal colon (Edwards and others 2000), whereas IFEE predominately affects the jejunum (Archer and others 2006). …”

Ischemia in equine intestine – mechanisms of injury and methods of treatment

“…Intestinal accumulation of eosinophils has been described in horses with experimentally-induced and naturally occuring colitis, I/R injury and parasitism , McConnico et al 1999, Edwards et al 2000, Archer et al 2006, Rötting et al 2008. Whereas eosinophils accumulate within the human gastrointestinal tract in disease (Rothenberg et al 2001), eosinophilic granulocytes are resident in the gastrointestinal lamina propria in healthy horses (Rötting et al 2008).…”