Page "Irritable bowel syndrome" Paragraph 14

Because there are many causes of diarrhea that give IBS-like symptoms, the American Gastroenterological Association published a set of guidelines for tests to be performed to rule out other causes for these symptoms.

These include gastrointestinal infections, lactose intolerance, and coeliac disease.

Research has suggested that these guidelines are not always followed.

Once other causes have been excluded, the diagnosis of IBS is performed using a diagnostic algorithm.

Well-known algorithms include the Manning Criteria, the obsolete Rome I and II criteria, the Kruis Criteria, and studies have compared their reliability.

The more recent Rome III Process was published in 2006.

Physicians may choose to use one of these guidelines, or may simply choose to rely on their own anecdotal experience with past patients.

The algorithm may include additional tests to guard against mis-diagnosis of other diseases as IBS.

Such " red flag " symptoms may include weight loss, gastrointestinal bleeding, anemia, or nocturnal symptoms.

However, researchers have noted that red flag conditions may not always contribute to accuracy in diagnosis – for instance, as many as 31 % of IBS patients have blood in their stool many possibly from hemorrhoidal bleeding.