Background: Allergic reactions to lettuce (Lactuca sativa) are not too frequent and few cases of systemic adverse reactions after its ingestion have been described.
Objective: We report a case of clinical sensitization to lettuce on a patient who presented mucocutaneous manifestations after its ingestion, with positive skin tests, histamine release test and serum specific-IgE to lettuce. The allergens responsible for this sensitization were also characterized by means of SDS-PAGE immunoblotting.
Materials and methods: We performed skin tests, histamine release test, serum specific IgE determination and CAP inhibition with lettuce and mugwort (Artemisia vulgaris) extracts. An aqueous and enriched lettuce (from loose leaf type) extract was subjected to SDS-PAGE immunoblotting for determination of its IgE-binding components.
Results and conclusions: CAP inhibition showed antigenic community between lettuce and mugwort. Four protein bands from the lettuce extracts with molecular weights of 50, 43, 39 and 16 kDa exhibited IgE-binding properties.