Postinfectious Irritable Bowel Syndrome

Abstract & Commentary

Synopsis: Some patients seem to develop chronic irritable bowel syndrome following an episode of gastroenteritis, possibly based on excessive mucosal serotonin release.

Source: Spiller RC. Gastroenterology. 2003;124:1662-1671.

Irritable bowel syndrome (IBS) is extremely common, but its protean characteristics make diagnosis and therapy obscure. Many studies have found between 6% and 17% of IBS patients dating onset of IBS symptoms to an acute attack of gastroenteritis. Spiller describes 35% of his own diarrhea-predominant IBS patients as having such a history. Risk seems highest if gastroenteritis symptoms are prolonged.

Women develop postinfectious IBS 3 times more often than men, and patients scoring high on test scales measuring hypochondriasis have an elevated relative risk. Vomiting during gastroenteritis and elevated age both seem to be protective against development of IBS after gastroenteritis. Infection with Campylobacter is much more likely to lead to this syndrome than Salmonella. Elevated T lymphocytes and enteroendocrine cells are seen chronically in the mucosa of postinfectious IBS. There is evidence for increased mucosal serotonin release in this syndrome. Postinfectious IBS is associated with accelerated whole-gut transit and visceral hypersensitivity. Differential diagnosis includes microscopic colitis, Crohn’s disease, small bowel bacterial overgrowth, drug-related symptoms (antibiotics, ACE inhibitors, PPIs, statins), and celiac disease. Treatment is nonspecific but might include loperamide, tricyclic antidepressants, serotonin antagonists, bile acid binding agents, and probiotics. Prolonged bismuth administration and chronic antibiotics also have been suggested.

Comment by Malcolm Robinson, MD, FACP, FACG

This article is of interest to primary care physicians since they are likely to be the first to identify these difficult patients. It is also possible that prompt intervention in gastroenteritis could decrease the subsequent development of chronic IBS. It seems likely that more information will become available to guide our practices in this area and in the overall management of IBS.

Dr. Robinson is Medical Director, Oklahoma Foundation for Digestive Research and Clinical Professor of Medicine, University of Oklahoma College of Medicine, Oklahoma City, OK.