DAO Deficiency seems to be more prevalent in population with inflammatory bowel diseases. It has been mainly detected in patients with colon cancer.
Ulcerative colitis and Crohn disease, pathologies with DAO Deficiency, are always monitored when developing any study related to endogenous histamine accumulation. Normally, when distributing patients in controls and patients with DAO Deficiency, those subjects with inflammatory bowel diseases are usually excluded.
DAO Deficiency has also been demonstrated in postoperative bowel. Diamine Oxidase is mainly located in the small bowel and if part of the mucosa decreases, so does the enzyme production area.
In Crohn’s disease patients, where DAO activity in the intestinal bowel is reduced by 50% regarding healthy population, a higher recurrence rate of the disease has been observed after surgery (mainly in those with low enzyme activity). Therefore, DAO is said to be a useful marker to foresee recurrence risks or complications in CD.