Comments: HIV, longer duration of HIV, and mitochondrial toxicity may play a role in damaging GI tract and leading to symptoms described below. This area has received little research attention. And doctors and patients don’t pay much attention to GI symptoms any more.

LAS VEGAS (Reuters Health) – Many patients with unexplained gastrointestinal (GI) symptoms have fructose intolerance, according to study findings presented Monday at the 66th Annual Scientific Meeting of the American College of Gastroenterology.

Unexplained bloating, flatus, and distension are common GI complaints. While much attention has been paid to lactose intolerance as a potential cause, fructose intolerance has received relatively little attention.

Dr. Young K. Choi and colleagues from the University of Iowa in Iowa City administered a fructose breath test to 219 patients with unexplained GI symptoms. The patients were also given a symptom questionnaire and assessed for irritable bowel syndrome (IBS).

Nearly 80% of patients had a positive breath test, the researchers note. Furthermore, the fructose given during the test reproduced the GI symptoms of 58% of patients. Based on questionnaire results, 130 of 159 patients met ROME I criteria for IBS.

“We were quite surprised to find such a high prevalence of fructose intolerance,” Dr. Choi told Reuters Health. “The results also suggest that many people with IBS have underlying fructose intolerance,” he added. However, “the patients we studied were referred to us by outlying centers, so it is hard to know the actual prevalence of fructose intolerance.”

“The fructose breath test is probably not performed at most community hospitals,” Dr. Choi noted. “The test is somewhat time-consuming, but relatively simple to perform.” Further studies are needed to better characterize the problem, he said. Until then, it is important for physicians to recognize the problem because institution of a low fructose diet may improve symptoms.