Anais Brasileiros de Dermatologia
On-line version ISSN 1806-4841
ANDRADE, Pedro; BARROS, Luísa and GONCALO, Margarida. Type 1 Ig-E mediated allergy to human insulin, insulin analogues and beta-lactam antibiotics. An. Bras. Dermatol. [online]. 2012, vol.87, n.6, pp.917-919. ISSN 1806-4841. http://dx.doi.org/10.1590/S0365-05962012000600018.
Insulin, a crucial therapeutic agent for diabetes mellitus, has been rarely associated with hypersensitivity events. We present a 69-year-old type-2 diabetic patient with urticariform lesions on the sites of subcutaneous injection of insulin. The patient denied any known allergies, except for an unspecific cutaneous reaction after intramuscular penicillin administration in childhood. Prick tests revealed positive reactions to all tested human insulins and insulin analogues. Serum IgE levels were above normal range and RAST tests were positive for human, bovine and porcine insulins, as well as beta-lactams. Type 1 IgEmediated allergy to insulin analogues demands a prompt diagnosis and represents a significant therapeutic challenge in diabetic patients.
Keywords : Diabetes mellitus, type 2; Drug hypersensitivity; Insulin; Penicillins.