Physicians definitively links irritable bowel syndrome and bacteria in gut

An overgrowth of bacteria in the gut has been definitively linked to Irritable Bowel Syndrome in the results of a new Cedars-Sinai study which used cultures from the small intestine. This is the first study to use this "gold standard" method of connecting bacteria to the cause of the disease that affects an estimated 30 million people in the United States.

Previous studies have indicated that bacteria play a role in the disease, including breath tests detecting – a byproduct of bacterial fermentation in the gut. This study was the first to make the link using bacterial cultures.

The study, in the current issue of Digestive Diseases and Sciences, examined samples of patients' small bowel cultures to confirm the presence of small intestinal bacterial overgrowth – or SIBO – in more than 320 subjects. In patients with IBS, more than a third also were diagnosed with bacterial overgrowth, compared to fewer than 10 percent of those without the disorder. Of those with diarrhea-predominant IBS, 60 percent also had bacterial overgrowth.

"While we found compelling evidence in the past that bacterial overgrowth is a contributing cause of IBS, making this link through bacterial cultures is the gold standard of diagnosis," said Mark Pimentel, MD, director of the Cedars-Sinai GI Motility Program and an author of the study. "This clear evidence of the role bacteria play in the disease underscores our clinical trial findings, which show that antibiotics are a successful treatment for IBS."

IBS is the most common gastrointestinal disorder in the U.S., affecting an estimated 30 million people. Patients with this condition suffer symptoms that can include painful bloating, constipation, diarrhea or an alternating pattern of both. Many patients try to avoid social interactions because they are embarrassed by their symptoms. Pimentel has led clinical trials that have shown rifaximin, a targeted antibiotic absorbed only in the gut, is an effective treatment for patients with IBS.

"In the past, treatments for IBS have always focused on trying to alleviate the symptoms," said Pimentel, who first bucked standard medical thought more than a decade ago when he suggested bacteria played a significant role in the disease. " who take rifaximin experience relief of their symptoms even after they stop taking the medication. This new study confirms what our findings with the antibiotic and our previous studies always led us to believe: are key contributors to the cause of IBS."

Related Stories

Recommended for you

Global Ebola toll rises to 5,689: WHO

1 hour ago

The World Health Organization said Thursday that the global death toll from the Ebola virus had increased to 5,689 out of a total of 15,935 cases of infection, mainly in western Africa.

Ebola vaccine promising in first human trials

12 hours ago

Researchers say they're a step closer to developing an Ebola vaccine, with a Phase 1 trial showing promising results, but it will be months at the earliest before it can be used in the field.

At one month, US Ebola monitors finding no cases

15 hours ago

The U.S. program that requires weeks of monitoring for travelers from African countries with Ebola reaches the one-month mark Thursday. And so far, no cases of the disease have turned up.

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.