WHEN ANAPHYLAXIS IS THE MYSTERY, RE-EXAMINE THE HISTORY

Abstract

Introduction Anaphylaxis, a potentially severe and sometimes fatal allergic reaction, is a risk for children with food allergies. Parents worry that their children may experience significant allergic reactions even without direct ingestion of known allergens (via inhalation, contact, etc.), although this is extremely uncommon. We present an adolescent patient with multiple food allergies who was having unexplained anaphylaxis only at school, and the investigation to determine the cause. Case Description A 15-year old boy with >12-year history of allergies to chickpea, peanut, lentil, green pea, and tree nuts reports four allergic reactions. All occurred during or after gym class immediately following lunch; one reaction required two doses of epinephrine and emergency department care. He had no known accidental exposures to known allergens. His mother was worried about food residue and/or latex on gym equipment, but he tolerated gym class in other schools. Initially we raised concern for food-dependent exercise induced anaphylaxis, but he had no problem with exercise outside school. Labs confirmed multiple legume allergies; tryptase was 3. We discovered that en route to gym after lunch on each reaction day, he walked past a cooking class where beans were prepared. He was reacting to aerosolized bean allergen. Discussion While it was initially unclear what caused the patient's symptoms, it was the detailed history that eventually led to the diagnosis. There are reports of legume allergic patients having reactions to aerosolized legumes, even if those particular legumes had never been ingested. Our patient's symptoms resolved after taking a different path to gym class.