Serum chitotriosidase activity in gaucher patients on enzyme replacement therapy (ERT)

Objective: Changes of serum chitotriosidase activity during Ceredase® treatment of Gaucher patients. Design and Methods: Ten Gaucher patients were treated with Ceredase for up to 30 months. Serum or plasma chitotriosidase activity was measured using 4-methylumbelliferyl-β---D-N, N′,N″ triacetyl-chitotrioside. Results: In untreated patients, serum chitotriosidase activity did not depend on the patient’s age and was not a measure of clinical status, type or progress of the disease. Chitotriosidase activity declined during treatment with Ceredase, but still remained high. The largest decline in enzyme activity was observed in patients with type III of the disease who had intact spleens; splenectomized type III patients, and type I patients reacted more slowly. Conclusions: Serum chitotriosidase activity may indicate that a patient has reacted to treatment, however, it can not be considered a direct marker of treatment effectiveness.