Skin-test reactivity to egg protein--exposure by inhalation compared with ingestion

Of two hundred and sixty-seven subjects exposed to egg by ingestion only, forty-eight were skin (prick)-test positive to egg material. All forty-eight subjects also reacted to other allergens on skin testing, forty-seven (98%) to allergens associated with respiratory allergy. Of thirteen subjects exposed to egg by inhalation in their workplace (and ingestion) two were skin-test-positive to egg, both also reacting to respirable allergens. Thus, inhalation of egg antigen does not greatly influence skin-test reactivity to eggs as determined by comparing the ratio of egg skin-test-positives to total skin-test-positives in the egg groups ingesting and inhaling egg antigen, i.e. 48:218 vs 2:6. In terms of the pulmonary response to inhaled eggs there were equal numbers of symptomatics with positive skin tests to common allergens as there were symptomatics with negative skin tests. Thus, an allergic predisposition shown by a positive skin test to common allergens does not predict nor preclude development of a pulmonary reaction to inhaled egg material.