Chitotriosidase: A marker for the diagnosis and follow-up of Gaucher disease

Objectives Plasma Chitotrisidase, a macrophage marker, is extremely increased in patients with Gaucher disease (-glucocerebrosidase deficiency). The aim of this study was to check plasma chitotriosidase as a reliable marker for the diagnosis and follow-up of Gaudier disease. Methods Chitotriosidase was measured fluorimetrically in nine patients with Gaucher disease type I and one subject with Gaucher disease type II. They have been diagnosed and are regularly followed-np at the Division of Pédiatrie Neurology, Department of Pediatrics, University of Catania. Enzyme replacement therapy with alglucerase was performed in four subjects at dosage of 20-60 U/Kg per month. Results Eight out of nine patients with Gaucher disease type I and one studied patient with type II had a striking increase of chitotriosidase in plasma (median 6508 nmoles/h/ml; range 2018-58000) with respect to control subjects (median 37.5 nmoles/h/ml; range 6-110). One Gaucher patient, had extremely low chitotriosidase level (chitotriosidase deficiency). In 4 patients on enzyme replacement therapy for one year, in addition to the amelioration of the clinical symptoms and hematological parameters, plasma chitotriosidase levels were about 50% of the initial value. Conclusions These findings suggest that plasma chitotriosidase is a reli- able and promptly evident marker for the diagnosis of Gaucher disease. Moreover it appears to be an additional parameter to verify the efficacy and to optimise the dosage of enzyme replacement therapy.