Clinical Features of Sulfite-Sensitive Asthmatics

Background:Sulfiting agents are widely used as preservatives and antioxidants in foods, beverages and drugs including bronchodilators. There have been reports of sulfite-related reactions such as anaphylaxis, urticaria, angioedema, abdominal discomfortness as well as bronchospasm. Several investigators reported that sulfite-sensitive asthmatic patients comprised from 3.9% to 8.2% of all asthmatic patients and its prevalence was higher in steroid-dependent group than in steroid-independent group. Subjects and Method:We performed oral provocation test with sodium bisulfite and aspirin in 17 asthmatic patients who have experienced aggravation of their symptoms after administration of drugs or foods. All of them were steroid dependent asthmatics. We observed clinical symptoms and steroid requirements from 1 to 18 months. Result:Ten of them showed severe bronchoconstriction after the ingestion of sodium bisulfite (50 to 200 mg) within 30 minutes. Concurrent aspirin intolerance was noted by oral provocation test in four cases (40%). Three of them showed positive responses on skin prick test with sulfite (10 or 100 mg/ml). Mean total eosinophil counts was at asthmatic attack. And there was no significant responses on skin prick test and IgE-RAST to common inhalant allergens. After complete avoidance from sulfite containing foods and drugs as well as antiasthmatic medication for 1 to 18 months, nine of them (90%) could stop or reduce the steroid requirements. ConcIusion:It was suggested that severe steroid dependent and intrinsic type of asthmatic patients should be evaluated for sulfite-sensitivity.