Clinical Case of Drug Allergy to Enzyme Replacement Therapy in a Patient with Mucopolysaccharidosis Type II

Abstract

Background. Enzyme replacement therapy (ERT) with iduronate-2-sulfatase recombinant forms (idursulfase and idursulfase beta) is effective for the management of mucopolysaccharidosis type II (MPS II). Patients with Hunter syndrome require lifelong ERT that can negate endogenous enzyme deficiency. However, hypersensitivity reactions may occur during ERT, and they significantly complicate the implementation of vital therapy.Clinical case description. This article describes clinical case of a child with hypersensitivity reaction to ERT. The patient with confirmed diagnosis of MPS II was administrated with idursulfase. Then, the drug was replaced with idursulfase beta due to the allergic reaction. Thus, even after the drug change, side effects maintained without sustained improvement with underlying glucocorticosteroids (GCS), antihistamines and with decreased infusion rate. Concerning the vital need to continue ERT, this patient with drug allergy to this pharmacotherapeutic group was further administered with combined therapy of cyclosporine and omalizumab. Personalised protocol for the administration of idursulfase beta with desensitization was developed. Such experience was firstly described In Russian patient.Conclusion. The presented personalised combination therapy made it possible to prevent hypersensitivity reactions during ERT in the patient with MPS II.