Post-infectious IBS has genetic link too

MONTREAL, Feb. 1 (UPI) -- The exact cause of post-infectious irritable bowel syndrome remains unknown but Canadian researchers found both an environmental trigger and genetic factors.

Studies of victims of the Walkerton, Ontario, tainted drinking water tragedy have led researchers to discover DNA variations in genes that increase the risk of developing post-infectious irritable bowel syndrome.

Study leader Alexandra-Chloe Villani of McGill University in Montreal, John K. Marshall of McMaster University in Hamilton, and Denis Franchimont, formerly of McGill, say post-infectious irritable bowel syndrome is a functional bowel disorder that has an acute onset after an episode of gastroenteritis.

"These patients suffer from chronic abdominal pain, discomfort, bloating and disturbed defecation in the absence of any detectable structural or biochemical abnormalities," the researchers say in a statement.

About 10 years ago, the municipal water supply of Walkerton was contaminated with E. coli and Campylobacter jejuni -- bacteria commonly found in animal feces -- leading to a public health disaster. Seven people died, 2,300 suffered symptoms and of the 2,300, 36 percent developed post-infectious irritable bowel syndrome.

"The biological implications of the identified genetic risk factors emphasize the important roles of the gut microbial flora, intestinal barrier function and inflammatory pathways in contributing to the onset of post-infectious irritable bowel syndrome," Villani says.

The finding is published online ahead of print in the March edition journal Gastroenterology.