Hypersensitivity reactions to BL can be classified according to the time they occur after drug administration.(32,33) Immediate reactions occur within 1 to 6 hours after BL administration, and are usually mediated by IgE.(33,34)They are clinically translated as urticaria, with or without angioedema, and anaphylaxis. The gene discussed is IGHE; the disease is anaphylaxis.