LEUVEN, Belgium — Irritable bowel syndrome is a chronic and sometimes debilitating condition leaving many people in pain on a regular basis. Making things worse, doctors don’t have a great handle on IBS and often diagnosis it based only on a patient’s symptoms. Now, a new study may have uncovered the cause of this disorder in the large intestine.
Researchers from Katholieke Universiteit Leuven in Belgium say they’ve discovered similarities between how people with IBS experience abdominal pain and how some people with allergies react to food.
Discovering this mechanism could be key to beginning new treatments and therapies for patients with the debilitating condition. Around one in five people deal with IBS, which causes them abdominal pain, cramping, bloating, and changes in their bowel movements.
While gluten-free diets can provide some relief, researchers did not understand why since many patients are not allergic to the foods they’re eating or have celiac disease. A team of gastroenterologists at KU Leuven says people with IBS frequently report their symptoms often begin after food poisoning.
In their study, they injected mice with a stomach bug and then with an egg white protein that is common in experiments because it provokes an immune response. Once the infection cleared, the mice then received the protein again to see if their immune systems had become sensitized to it.
Treating IBS like a food allergy?
The results reveal the mice now had IBS, along with digestive intolerance and increased abdominal pain. Researchers then successfully unpacked the series of events in the immune response that connects the digestion of egg white protein to the activation of the mast cells. Significantly, this immune response only occurs in the part of the intestine infected by the disruptive bacteria. It did not produce more general symptoms of a food allergy.
Study authors then experimented with 12 IBS patients and discovered that people reacted in the same way as the mice. Treating patients with antihistamines that stopped the reaction resulted in a lot of improvement.
“Very often these patients are not taken seriously by physicians, and the lack of an allergic response is used as an argument that this is all in the mind, and that they don’t have a problem with their gut physiology,” study lead author Professor Guy Boeckxstaens says in a university release. “With these new insights, we provide further evidence that we are dealing with a real disease. At one end of the spectrum, the immune response to a food antigen is very local, as in IBS. At the other end of the spectrum is food allergy, comprising a generalized condition of severe mast cell activation, with an impact on breathing, blood pressure, and so on.”
“Knowing the mechanism that leads to mast cell activation is crucial, and will lead to novel therapies for these patients. Mast cells release many more compounds and mediators than just histamine, so if you can block the activation of these cells, I believe you will have a much more efficient therapy,” the professor concludes.
The findings appear in the journal Nature.
SWNS writer Joe Morgan contributed to this report.