Idursulfatase Therapy in Mucopolysaccharidosis Type II: After 2.5 Years of Treatment—No Benefit for Older Patients With Multisystem Involvement

Abstract

We were intrigued by the article of the Hoffman et al. [ [1] Hoffmann B. Schulze-Frenking G. Al-Sawaf S. et al. Hunter disease before and during enzyme replacement therapy. Pediatr Neurol. 2011; 45: 181-184 Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar ]. We have observed three patients treated with Hunter syndrome with idursulfatase (0.5 mg/kg/weekly) for 2.5 years (ages at initiation of treatment: 5.5, 6, and 12.5 years). All three children were mentally retarded (intelligence quotients, 34-80) and manifested a coarse face, hepatosplenomegaly, and stiff joints. Kyphosis, epilepsy, and stunted growth were evident in one child. No patient demonstrated myocardiopathy, deafness, or corneal opacities. Hunter Disease Before and During Enzyme Replacement TherapyPediatric NeurologyVol. 45Issue 3PreviewMucopolysaccharidosis type II (Hunter disease) is a lysosomal storage disease attributable to X-linked deficiency of the enzyme α-L-iduronate-sulfatase. Because of this deficiency, glycosaminoglycanes accumulate in various tissues and body fluids. We describe three patients representing the broad spectrum of Hunter disease and their response to enzyme replacement therapy. Patient 1 did not manifest central nervous system involvement, patient 2 manifested moderate neurologic disease, and patient 3 had already manifested a severe neurologic course during early infancy. Full-Text PDF ResponsePediatric NeurologyVol. 46Issue 3PreviewGucev and Tasic report on their experience with idursulfatase in the treatment of three patients with Hunter disease, and conclude that “no effects for older patients with multisystem involvement” are evident. Nevertheless, they describe a significant reduction of liver and spleen size during treatment with enzyme replacement therapy, without providing information about possible secondary effects of reduced organomegaly, e.g., breathing and exhaustion may be improved. Based on the fact that two children in their cohort had to undergo surgical procedures, Gucev and Tasic also concluded that no effects were evident regarding joint stiffness over a period of 2.5 years. Full-Text PDF