Systemic reactions to allergy skin tests

Background: Skin testing is a common diagnostic tool in allergy. It is considered a safe procedure, although systemic reactions have been reported. Objective: To identify the systemic reaction rates of allergy skin tests and to determine the clinical outcome of such reactions. Method: This retrospective study used a computerized database at the Mayo Clinic to identify patients who developed systemic reactions to skin tests. Altogether 497,656 skin tests were performed on 18,311 patients from January 1992 to June 1997. Skin puncture tests were performed on 16,505 patients. Skin puncture and intradermal skin tests were performed on 1,806 patients. Systemic reactions were evaluated and treated by physicians. Results: There were 6 systemic reactions, an overall rate of 33 systemic reactions per 100,000 skin tests. All six patients had asthma. The systemic reaction rates for latex skin testing was 152 or 228 reactions per 100,000 latex skin tests, to penicillin and antibiotics 72 reactions per 100,000 penicillin and antibiotics skin tests, and to aeroallergens 15 or 23 reactions per 100,000 aeroallergen skin tests. The systemic reaction rate for skin puncture test was 30 reactions per 100,000 skin puncture tests, for skin puncture and intradermal skin tests, the rate was 55 reactions per 100,000 skin puncture and intradermal skin tests. All 6 patients were treated and dismissed within 1 hour after treatment. Conclusion: The systemic reaction rate to skin tests was very low. Systemic reactions were mild and all patients recovered fully within 1 hour.