Occupational IgE-mediated psyllium allergy in contemporary gluten-free and vegan baking: A case of allergic rhinitis.

Psyllium (from Plantago ovata; ispaghula) is used as a dietary supplement and is supplied in the form of husk, granules, capsules, or powder. Consumers using psyllium-containing laxatives, healthcare workers handling these, and pharmaceutical workers in laxative-manufacturing plants are known to be at risk of sensitization and subsequent rhinitis, asthma, contact urticaria, and even anaphylaxis. To our knowledge, the case we present here is the first of baker's immunoglobulin E (IgE)-mediated occupational allergy due to psyllium exposure. Our patient, a 24-year-old female baker with no previous allergies, was referred to our clinic with suspected occupational rhinitis. After 1 year of baking with cereal flour or gluten-free flour-mix, she began to suffer from rhino-conjunctival symptoms during workdays. Skin prick tests with agents from the patient's workplace revealed allergies not only to wheat and rye flours but also to psyllium, with a remarkable 10 mm wheal. Subsequently, nasal provocation tests confirmed occupational allergic rhinitis to psyllium. We also found work-related sensitization to buckwheat, which she used in gluten-free baking. Due to the increased prevalence of celiac disease and the popularity of gluten-free and vegan food, psyllium has recently become a common ingredient in baking, used as a substitute for gluten or eggs. Bakers handle allergens such as these in high concentrations and this may lie behind the emergence of respiratory and dermal symptoms. It is essential to consider new or recenlty introduced materials as possible allergens if it is suspected that a baker has work-related respiratory or allergic symptoms.