Allergy and mucosal eosinophil infiltrate in ulcerative colitis.

Background: Data on allergy in ulcerative colitis (UC) have led to conflicting conclusions without proving any causal association. In this report we have investigated the presence of allergy and its possible relation with chronic colonic inflammation in patients with UC.

Methods: Fifty UC patients underwent clinical, endoscopic, and histologic evaluations. The allergologic study included family/personal history; prick/patch exposition to airborne, food, and contact allergens; total serum IgE; and quantification of eosinophils in peripheral blood and intestinal mucosa. Diagnosis of rhinitis, conjunctivitis, and asthma was confirmed by specific provocation tests. Fifty healthy subjects were studied as control group.

Results: A higher prevalence of allergic symptoms was found in patients (56%) and their first-degree relatives (52%) than in controls (18% and 26%) (P < 0.0001; P = 0.008). In patients skin tests showed increased rates of immediate (54%) and delayed-type (20%) hypersensitivity compared with controls (30% and 6%) (P= 0.01; P= 0.03). Diagnosis of allergic IgE-mediated disease was made in 19 cases and 6 controls (P= 0.01), and allergic contact dermatitis in 10 and 3, respectively (P= 0.03). IgE levels were higher in UC patients than in controls (P=0.02). No dose-response relationship was found between degree of colonic tissue eosinophilia and clinical. endoscopic, and histologic disease severity. The degree of colonic tissue eosinophilia was higher in the presence of skin reactivity to food allergens.

Conclusions: UC patients frequently show several markers of allergy. In particular, our data suggest an association between ulcerative colitis, tissue eosinophilia, and type-I allergy.