Introduction:

Mucopolysaccharidosis type II (MPS II) or Hunter syndrome is a lysosomal disease caused by deficiency of the enzyme iduronate-2-sulfatase, responsible for the degradation of glycosaminoglycans.

Case presentation:

Male patient diagnosed with MPS II at three years of age. The clinical picture included coarse facial features, splenomegaly, limited joint mobility, recurrent airway infections, and psychomotor retardation. Treatment with idursulfase was started and, after 24 months, his growth and joint mobility have improved; in addition, the volume of the spleen decreased, and he has not presented respiratory infections, but the neurological disorders persist.

Conclusions:

Currently, the availability of idursulfase, as enzyme replacement therapy, has improved the prognosis of MPS II patients.