A case of Muscat grape-induced food-dependent exercise-induced anaphylaxis identified by stepwise challenge testing

Food-dependent exercise-induced anaphylaxis (FDEIA) is a distinct form of immunoglobulin E–mediated food allergy in which symptoms occur only when ingestion of the culprit food is followed by exercise or another cofactor, such as nonsteroidal anti-inflammatory drugs. We report an adolescent girl with recurrent FDEIA in whom stepwise food-exercise challenge testing identified Muscat grape as the most likely trigger despite negative routine in vitro testing. This case highlights the importance of stepwise provocation testing when FDEIA is suspected.