The Evolving Contribution of Cannabis Exposure to Peanut Allergy Development: A Case Report.

Nonspecific lipid transfer proteins are small, heat-stable proteins found in a variety of plant foods and, although once thought to be largely confined to Mediterranean populations, are increasingly recognized as clinically relevant allergens in diverse geographic regions, including North America. We describe a two-year-old boy who developed rapid-onset erythema after peanut ingestion, followed weeks later by recurrent eyelid swelling after outdoor exposure. Evaluation demonstrated sensitization to peanut with elevated Ara h 9, along with sensitization to mugwort and cannabis in the context of passive cannabis smoke exposure. This case suggests that both mugwort allergy and cannabis sensitivity may have contributed to Ara h 9 sensitization and subsequent peanut allergy. Importantly, the present case also presents novel insight into the unexpected, early onset of lipid transfer protein sensitization in children.