Enhanced histamine metabolism: a comparative analysis of collagenous colitis and food allergy with respect to the role of diet and NSAID use

Abstract:Objectives and Design: To compare clinical data and histamine metabolism of patients with collagenous colitis with those of food allergy. Methods: In 17 patients with collagenous colitis, clinical findings (diarrhoea, abdominal pain) were recorded. Plasma (for histamine) and 12-h-urine (for histamine and n-methylhistamine, all measured by RIA) were collected during two days with an unrestricted diet followed by two days with an hypoallergenic. The clinical data and measured values were compared with those from patients with confirmed food allergy (n = 21) and controls (n = 41). Results: Patients with collagenous colitis were found to present with significantly more liquid stools than patients with food allergy (p < 0.001) during both types of diet, but they did not experience more abdominal pain. N-methylhistamine in 12-h-urine was significantly increased during both types of diet in patients with collagenous colitis and food allergy when compared with controls (p < 0.001 for all). Patients with food allergy - but not those with collagenous colitis - showed a significant decrease of severity of pain (p < 0.05) when the diet was changed to the elimination protocol. Conclusion: Histamine is extensively produced and metabolised in patients with collagenous colitis. In contrast to food allergy, the allergenic potency of the administered food seems not to influence histamine production in collagenous colitis. However, histamine metabolism corresponds with the clinical activity in both patients with food allergy and collagenous colitis.