JEADV
LETTER TO THE EDITOR
Is isotretinoin treatment safe in patients with known peanut allergy? Editor A 12-year-old boy was referred by his dermatologist who wanted to treat his severe acne vulgaris using isotretinoin (Roaccutaneâ). In the past, he developed urticaria, facial oedema and dyspnoea (grade 2 anaphylaxis; classification of Ring and Messmer)1 after peanut consumption. Diagnosis of peanut allergy was confirmed by specific IgE. Prescribing information leaflets state that oral isotretinoin is contra-indicated in patients with known soybean or peanut allergy, because of the presence of soybean oil in the capsule and the known cross-reactivity between soybean and peanut.* To the best of our knowledge, all European commercialized oral isotretinoin formulations contain soybean oil. As a consequence, patients with known allergy to soybean or peanut cannot be treated with oral isotretinoin. Since isotretinoin is an important dermatologic treatment option, and because symptoms from soy cross-reactivity in peanut-allergics are mostly mild, we assessed whether oral challenge can be used to evaluate the safety of isotretinoin in known peanut-allergic patients who have no soybean allergy. In our patient, total serum IgE was elevated (959 kIU/L). RAST and skin prick testing confirmed the presence of specific IgE for peanut (RAST 3.93 kU/L; wheal size 8 mm) but not for soybean (RAST
LETTER TO THE EDITOR
Is isotretinoin treatment safe in patients with known peanut allergy? Editor A 12-year-old boy was referred by his dermatologist who wanted to treat his severe acne vulgaris using isotretinoin (Roaccutaneâ). In the past, he developed urticaria, facial oedema and dyspnoea (grade 2 anaphylaxis; classification of Ring and Messmer)1 after peanut consumption. Diagnosis of peanut allergy was confirmed by specific IgE. Prescribing information leaflets state that oral isotretinoin is contra-indicated in patients with known soybean or peanut allergy, because of the presence of soybean oil in the capsule and the known cross-reactivity between soybean and peanut.* To the best of our knowledge, all European commercialized oral isotretinoin formulations contain soybean oil. As a consequence, patients with known allergy to soybean or peanut cannot be treated with oral isotretinoin. Since isotretinoin is an important dermatologic treatment option, and because symptoms from soy cross-reactivity in peanut-allergics are mostly mild, we assessed whether oral challenge can be used to evaluate the safety of isotretinoin in known peanut-allergic patients who have no soybean allergy. In our patient, total serum IgE was elevated (959 kIU/L). RAST and skin prick testing confirmed the presence of specific IgE for peanut (RAST 3.93 kU/L; wheal size 8 mm) but not for soybean (RAST
