Association Between Enteroliths and Gastric Ulcers in Horses

Enteroliths are stonelike concretions that may form in the horse’s large intestine. Small enteroliths may pass without any problems, but larger ones sometimes block the flow of material through the intestine, causing pain and tissue damage.

Gastric ulcers have been diagnosed in horses with colic and also in horses with enterolithiasis. Researchers at Chino Valley Equine Hospital in California hypothesized that horses affected by enterolithiasis might have a higher prevalence of gastric ulceration when compared to horses with large intestinal simple obstructions due to other causes. To test this hypothesis, they compared the prevalence of gastric ulceration in horses with enterolithiasis to horses with other types of large intestinal simple obstruction.

Records were examined for 148 horses that had surgery for removal of one or more enteroliths (case horses). Horses that had surgery for large intestinal simple obstructions other than enterolithiasis (control horses) were matched to case horses by age, sex, and breed. Gastric ulcers were diagnosed 68% of the case horses and in 31% of control horses. There was a significant association between enterolithiasis and gastric ulceration, and a greater prevalence in Thoroughbreds as compared to other breeds. Because of this positive association, it is suggested that gastroscopy is indicated for all horses diagnosed with enterolithiasis.