Hemp seed allergy

Question:

10/20/2022
I recently saw an elementary aged pediatric patient in clinic who presented with a history of anaphylaxis (generalized urticaria, facial angioedema, respiratory distress, and possible hypotension) 1 hour after drinking a smoothie with hemp seed. They had a large positive skin prick test for hemp seed and skin testing was negative for all other ingredients. IgE testing for hemp seed is pending. They have not had previous exposure to hemp or cannabis in the past. She has a history of mild intermittent asthma and tree pollen allergy (including birch pollen).

- Has hemp or cannabis allergy been described in a patient this young?
- Is it known if hemp seed storage proteins are cross reactive with pollens?
- It appears that there is some IgE cross reactivity between hemp and cannabis. What is the best guidance to offer this family with regards to allergen avoids and risk of future exposures? If the patient is exposed to cannabis smoke, could she have exposure to aerosolized seed protein? Is there risk of allergen exposure with hemp seed oil or CBD oil? Does hemp-based fabric have any measurable seed protein that could lead to sensitization or IgE mediated symptoms?