New Biomarker Blood Test Helps Seek Out IBS

Mark Pimentel, MD, director of the Cedars-Sinai Gastrointestinal Motility Program and Motility Laboratory, has developed a diagnostic test to identify patients with irritable bowel syndrome (IBS) based on a novel clinical biomarker for IBS. Currently, there is no biomarker assay for IBS, which is diagnosed based upon exclusion of other disorders and the Rome criteria.

A 2009 American College of Gastroenterology task force on IBS concluded that the symptom-based diagnostic criteria do not have ideal accuracy, and that the Rome criteria in particular have been inadequately specific with a sensitivity rate of about 75 percent.

The IBS blood test that Pimentel and his team developed measures the anti-vinculin antibodies to determine whether a patient is suffering from IBS. The test also potentially can distinguish IBS from inflammatory bowel disease (IBD) and reduce the need for unnecessary testing to rule out more serious conditions. The test has been validated in a large multicenter validation study using IBS, IBD and healthy control subjects. In this trial, the test specificity for IBS was 88 percent with a positive predictive value of 94 percent.

IBS is a common disorder that affects 10 to 15 percent of the adult population with symptoms such as cramping, abdominal pain, bloating, gas, diarrhea and constipation.