For the first time, a simple blood test may be the best way to determine if a patient is suffering from Irritable Bowel Syndrome (IBS), or another serious condition such as Inflammatory Bowel Disease (IBD), according to Cedars-Sinai physician researcher Mark Pimentel, MD, lead author of a multicenter clinical trial.
Researchers conclusively identified a test for antibodies that form against a particular protein, vinculin, found in the guts of patients, many of whom suffered acute gastroenteritis at some point.
"This is a major breakthrough. It is the first test with a high specificity for IBS, likely based on a pathological mechanism of the disease," said Pimentel, the director of the Cedars-Sinai GI Motility Program and the GI Motility Laboratory. Pimentel (pictured at right) is co-author of the study, and results were presented for the first time earlier this month at the American College of Gastroenterology's 78th Annual Scientific Meeting in San Diego, Calif.
In the study, 221 patients were evaluated; some had a diagnosis of IBS, some were diagnosed with IBD and some were healthy, with no symptoms. Anti-vinculin antibodies were significantly elevated in IBS patients as compared to those with IBD or those who were healthy.
"Until this study, there had been no accurate biomarkers identified specifically for IBS. The new blood test has the potential to distinguish IBS from IBD and reduce the need for unnecessary testing, expense and years of suffering," says Pimentel.
Irritable Bowel Syndrome is the most common gastrointestinal disorder in the U.S., afflicting 30 million people. Food poisoning has been identified as a significant risk factor for developing the disorder which is characterized by a cluster of symptoms including diarrhea, bloating and abdominal pain. But millions of patients are never diagnosed correctly. A simple blood test at the first sign of symptoms means patients who have IBS could get effective treatment sooner.
More than a decade ago, Pimentel went up against the conventional medical understanding of IBS when his research suggested the overgrowth of bacteria in the gut was a contributing cause of the condition. Today, antibiotics play a key therapeutic role in bringing relief to millions of patients. A definitive blood test for IBS would represent a significant new development.
The study was performed in collaboration with physician scientists at Beth Israel Deaconess Medical GAS in Boston.
Photo: Mark Pimentel, MD; antibodies attack healthy cells in the gastrointestinal tract of a patient with irritable bowel syndrome.