ABSTRACT
Gastric Ulcer Disease Gastric ulcer disease is a general term covering several different syndromes. The causes of gastric ulcers are multifactorial and differ from the squamous mucosa to the glandular mucosa. Lesions in the gastric squamous mucosa (Figures 5-1 and 5-2) result primarily from excessive exposure to hydrochloric acid (HCl).1,2 Other factors, including short-chain fatty acids, may contribute, but HCl is believed to be the primary cause of mucosal injury.3 The cause of ulcers in the gastric glandular mucosa is less well understood. Nonsteroidal anti-inflammatory drugs can cause gastric glandular mucosal ulcers in foals and adult horses, but the causes of spontaneous ulcers in this area of the stomach remain undetermined. Excessive acid does not appear to be a primary factor. In fact, the prevalence of ulcers in the glandular part of the stomach differs by region, from low in the oxyntic region to high in the antrum (Figures 5-3 and 5-4).1 Lesions in the antral mucosa and associated histologic changes resemble those caused by Helicobacter pylori in humans. Evidence for infection of the equine gastric antral mucosa by an uncharacterized species of Helicobacter has come from various studies, including polymerase chain reaction data,4
antibody data,5 and immunofluorescence data;6 however, no Helicobacter spp. have been cultured from horses and no association with clinical disease has been demonstrated to date.
