[Asthma due to disulfites].

Sulfites are recognized as food and drug additives responsible for anaphylactoid adverse reactions, especially in asthmatics. We report on 7 patients (6 females and one male) aged between 24 and 70 years, with preexistent asthma and/or rhinitis of the "intrinsic" type, who experienced severe, life-threatening asthmatic and urticarial reactions after ingestion of wine, salads and other food containing sulfites as preservatives or antioxidants. In a 70-year-old female anaphylactoid shock occurred after injection of a parenteral preparation of doxycycline containing disulfite and benzoic acid as preservative. The diagnosis was established by oral blind challenge tests with increasing doses of natrium disulfite, which provoked a 30% to 57% decrease in FEV1 at a 5 to 50 mg dose. Bronchospasm mainly occurred 15-30 minutes later and in one case one hour after oral disulfite intake. In two patients a severe, life-threatening asthmatic reaction occurred. In one patient with a positive scratch test of the immediate type to powdered natrium disulfite, the oral challenge was not done. Three other patients reacted one + positive. Only in one case was aspirin (ASS) intolerance also present, while the other 6 patients tolerated ASS in the oral provocation test. The pathogenetic mechanisms of sulfite sensitivity are not fully understood, but recent reports and our four cases with positive skin tests suggest an IgE-mediated hypersensitivity reaction in some patients. Food containing sulfites in Switzerland are listed. 5% of drug formulations, and 15% of injectables most frequently prescribed in Switzerland contain sulfites.(ABSTRACT TRUNCATED AT 250 WORDS)