Effects of enzyme replacement therapy on growth in patients with mucopolysaccharidosis type II

Mucopolysaccharidosis type II (MPS II; Hunter syndrome) is an X-linked, recessive, lysosomal storage disorder caused by deficiency of iduronate-2-sulfatase. It has multisystemic involvement, with manifestations in the brain, upper respiratory tract, heart, abdomen, joints and bones. Bone involvement leads to decreased growth velocity and short stature in nearly all patients. A therapeutic option for patients with MPS II is enzyme replacement therapy (ERT) with idursulfase (Elaprase®). We compared annual growth rates before and during ERT in 18 patients from Mainz, Germany, and Manchester, UK. Group 1 included nine patients who started ERT before 10 years of age; group 2 contained nine patie…