Contact hypersensitivity in atopic dermatitis.

From January 1990 to December 1994, a total of 84 patients (56 men and 28 women) with atopic dermatitis (AD) were referred to our Clinic for patch testing. The European standard series of allergens was applied to all subjects together with any additional series indicated in the case history. Sensitization to at least one of the allergens was found in 57.1% of individuals with AD. Positive reactions were more frequently determined in adults than in children with AD. Women and men were equally positive in epicutaneous testing. The commonest sensitizer was nickel sulfate (discriminative in 28.6%). Adult patients with atopic dermatitis significantly differed from patients with chronic urticaria or healthy controls in patch test positive results. Our findings suggest that allergic contact dermatitis is more common in patients with AD than generally assumed and that patch testing is a practicable and clinically worthwhile procedure for determining allergic contact dermatitis in patients with AD.