Anaphylaxis is rare in drug and food challenges in mastocytosis
Published online November 7, 2024
Patients with mastocytosis (MC) harbor increased numbers of mast cells and have an increased risk of anaphylaxis in response to various triggers. These can lead to severe anaphylactic reactions, including life-threatening symptoms such as unconsciousness and, in extreme cases, death. Most patients reacted to insect venoms, but reactions to drugs, or foods have also been reported. Many patients with MC avoid drugs and foods (-additives) because of a general fear of severe reactions. Thus, to prevent unnecessary avoidance and anxiety, proper allergy diagnostics are crucial. The gold standard diagnostic tool is challenge testing (CT). However, most centers avoid CT in MC because of safety reasons.
In a recent issue of The Journal of Allergy and Clinical Immunology: In Practice, Bent et al. present findings from a retrospectively study evaluating the safety and outcome of challenges to drugs and foods including food additives in patients with MC. Of 126 adult MC inpatients, 83 had a suspicion of food or drug hypersensitivity and 445 CTs were performed. History, clinical data and allergy test CT results were analyzed.
Most patients tolerated the challenges or reacted with only subjective symptoms confirming that in most MC patients the fear of severe reactions to food or drugs is not justified. Only 2.2% CTs in 9 patients resulted in anaphylaxis. Drugs elicited reactions in 2.4 % of patients: two patients to acetylsalicylic acid (2/39 tested patients, 5.1%), one to tramadol (1/12, 8.3%) and one to flurbiprofen (1/1). Anaphylaxis to food challenge was noted in 6/275 CTs (2.2%); two out of 48 (4.1%) to α-gal, two to other foods and two to sulfites. Flushing or diarrhea occurred to histamine in 5/48 (10.4%), but also in 5/50 (10.0%) placebo challenges strongly questioning its relevance. Patients with anaphylaxis in CT had more bone marrow mastocytosis and higher basal serum tryptase (71.3 vs. 44.3ug/l; p<0.05).
In summary, challenge-confirmed food and drug anaphylaxis was rare in MC patients and does not support general elimination diets or drug avoidance. Challenge is an appropriate diagnostic tool for MC patients, although in exceptional cases severe anaphylaxis has to be anticipated.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.
Full Article