"An estimated  million to  million Americans suffer from irritable bowel syndrome or IBS a gastrointestinal condition https that can cause miserable symptoms. Making it worse for many patients there hasnt been a conclusive test to diagnose whats wrong with them. Without proof of a physical cause some doctors considered IBS a psychological disorder. But that could finally change with the introduction of two simple new blood tests for spotting the disease. Dr. Mark Pimentel of CedarsSinai Medical Center in Los Angeles developed the tests. We now have a test to say you have a disease Pimentel told CBS News. Having a test like this shortens the time of suffering it shortens the time of investigation and accelerates getting the patient directly to treatment. The tests which measure antibodies in the blood were based on research suggesting that IBS may develop after infection https from a bacterial toxin found in food poisoning. Researchers believe the toxin triggers the immune system to attack a persons intestinal tract long after the toxin is gone. Irina Obenauer was diagnosed with IBS years ago after suffering from diarrhea and bloating but it took doctors a long time to rule out other possible diagnoses first. Theres always kind of a trend of the week that you had to go and get tested for and rule out and at the end of the day you dont feel better she said. She got the new blood test to confirm her diagnosis and when it came back positive she said she felt a sense of relief knowing IBS wasnt all in her head. Im not saying the symptoms went away she said but she started to feel more whole. CBS News chief medical correspondent Dr. Jon LaPook https who is also a practicing internist and gastroenterologist points out that the test is not perfect. While a positive test result is highly suggestive of IBS only  percent of patients with IBS tested positive meaning that many people who test negative could in fact still have the condition."