Clinical response to long term enzyme replacement treatment in children, adolescent and adult patients with Hunter syndrome.

BACKGROUND AND OBJECTIVE

Since enzyme replacement treatment (ERT) with idursulfase is available for Hunter syndrome (HS; mucopolysaccharidosis type II), for the first time, disease progression can be limited and organ damage reduced or prevented.

PATIENTS AND METHODS

We described retrospectively the clinical evolution of eight HS males, treated with ERT and followed in routine clinical practice in Hospital Infantil La Fe (Valencia, Spain).

RESULTS

We studied three children, three adolescents and two adults. Time from diagnosis to ERT ranged from 13.7 to 0.2 years, and duration of ERT ranged from 24 to 77.1 months. From the start of ERT, weight and height increased in children and adolescents and remained stable in adults. Glycosaminoglycans (GAG) decreased in all patients; in patient 5 (aged 23 years), we observed the highest reduction (86%) with recovery of carpal tunnel syndrome, splenomegaly and a decrease in nocturnal oxygen dependence.

CONCLUSION

Our results show that ERT improve respiratory impairment and organomegalies and decrease GAGs levels in all patients including children, adolescent and adults. While cardiac manifestations and facial features stabilized, responses in other parameters were heterogeneous.