I have a question regarding a pepper allergy vs intolerance in a young child. She first reacted at 12 months old to "rajas" or poblano pepper tacos with hives on her back, buttocks and upper thighs, angioedema of the hands and cough. All other congested foods were negative on skin testing and ingested since without reaction. Second reaction was similar foods with jalapeno pepper which was similar, subsequent reactions to bell pepper, guajillo and salad dressings with "spices" listed and/or paprika occurred where she started to grab at her tongue and have more eczematous reactions through the age of 4. She tolerates black pepper without a problem and also has ingested serrano pepper with no reactions in a green salsa. Each reaction responded immediately to Benadryl, once requiring oral steroids most recently which seemed more severe than the past rashes/reactions covering entire back/buttocks/legs/chest/abdomen, never requiring EpiPen administration. Paprika extract on skin testing was 1+, fresh peppers were not tested for fear of irritant reaction. I have been told by a colleague this could be because of TRP channels. My questions are: is this IgE mediated or through TRP channels or some other mechanism? What is the likelihood she will outgrow it? Should EpiPen be consistently given in cases like this?
We contacted Sami Bahna, MD, DrPH and his comments are below.
This young child’s medical history is convincing of multiple IgE-mediated reactions to certain types of peppers or “spice mixture”. Published studies on diagnostic tests for spices by SPT and sIgE are very limited and, in general, showed low reliability. Verification requires a cautious titrated challenge under supervision. Non-IgE mediated reactions are primarily type IV (contact dermatitis). More info is in a review article (Ann Allergy Ashma Immunol 2011;107:191).
For this youngster, in addition to strict avoidance, I would prescribe epinephrine auto-injector –overusing it is better than not, particularly since her latest reaction was severer than before. Outgrowing this allergy is very likely though may take several years. Many allergens in spices are resistant to processing (heat, grinding, drying, freezing, pickling).
I hope this information is of help to you and your patient.
All my best.
Dennis K. Ledford, MD, FAAAAI