Whereas celiac disease affects the small intestine, IBS affects the colon, or large intestine (the part of the digestive tract that stores stool). The exact cause is unknown. Among the most common features of IBS are abdominal pain or discomfort, cramping, bloating, and gas that may be relieved by a bowel movement. Some people with the disorder have constipation, others have diarrhea, and some have both. Some have a whitish mucus in their stool. Patients can also have nausea, fatigue, a sensation of fullness after even a small meal, and vomiting.
In addition, symptoms of IBS can be made worse by large meals; certain medicines; eating wheat, rye, barley, chocolate, or milk products; drinking alcohol or caffeinated beverages such as coffee, tea, or colas; and stress or conflict.
There is no specific test for IBS. Doctors first look for other disorders that might be causing the patient's symptoms. If they don't find any other medical explanation, they use a list of features called The Rome Criteria to identify patients who might have IBS.
What Should Patients With Irritable Bowel Syndrome Ask Their Doctors About Celiac Disease?
Patients with IBS should ask their doctors to make sure they don't have celiac disease. With so many similarities, it's not surprising that medical researchers have found a high rate of celiac disease in patients with IBS. One British study found that the chance of having celiac disease was 7 times higher for patients with IBS than for the general public. In an Iranian study, nearly 10% of patients with IBS also had celiac disease. In these patients, symptoms either improved or disappeared when they adopted a gluten-free diet.Many researchers have recommended that everyone with IBS be automatically tested for celiac disease. When American doctors studied the cost-effectiveness of testing for celiac disease in all patients with suspected IBS, they found that celiac testing would be cost-effective even if it turned out that only a few patients actually had the disease, and even if those few patients had only a small quality-of-life improvement with a gluten-free diet.
The bottom line? If you've been diagnosed with IBS, talk to your doctor about tests for celiac disease, too. If you have celiac disease but don't treat it with a gluten-free diet, you're at risk for serious complications.
Sources:
Sanders DS et al. Association of adult coeliac disease with irritable bowel syndrome: a case-control study in patients fulfilling ROME II criteria referred to secondary care. Lancet 2001;358:1504-8.
Shahbazkhani B et al. Coeliac disease presenting with symptoms of irritable bowel syndrome. Aliment Pharmacol Ther 2003;18:231-5.
Mein SM, Ladabaum U. Serological testing for coeliac disease in patients with symptoms of irritable bowel syndrome: a cost-effectiveness analysis. Aliment Pharmacol Ther 2004;19:1199-210.
