Histamine plasma levels and elimination diet in chronic idiopathic urticaria (original) (raw)

Objective: The aim of this study was to evaluate the effects of an oligoantigenic and histamine-free diet on patients affected with chronic idiopathic urticaria (CIU). Design: Ten patients with chronic idiopathic urticaria were prescribed an oligoantigenic and histamine-free diet for 21 days, followed by serial and controlled reintroduction of foods during a further 70 days. Modi®cation in clinical illness as well as histamine plasma levels, post-heparin plasma diamine oxidase (DAO) and intestinal permeability were evaluated. Results: The oligoantigenic and histamine-free diet induced a signi®cant improvement of symptoms (P`0.05). Moreover, CIU patients on free diet showed higher histamine plasma levels (P`0.05 vs post-diet and vs controls) that fell to control levels during the oligoantigenic and histamine-free diet. Post-heparin plasma diamine oxidase values were slightly reduced and were unchanged during the diet as well as intestinal permeability, which was always normal in all patients. Conclusions: These data suggest that histamine plays a major role in chronic idiopathic urticaria. The ®nding of normal intestinal permeability suggests that a morphological damage of intestinal mucosa should be excluded in these patients. However, the presence of low levels of post-heparin plasma diamine oxidase may indicate a subclinical impairment of small bowel enterocyte function that could induce a higher sensitivity to histaminerich or histamine-producing food. Descriptors: chronic idiopathic urticaria; diet; histamine; diamine oxidase; intestinal permeability