Abstract

As an important group among inherited metabolic disorders, lysosomal storage diseases represent a major healthcare concern. To date, more than 40 different lysosomal storage diseases, characterised by the deficiency of a lysosomal protein, have been identified. The aim of this study was to evaluate the significance of lysosomal enzyme testing for the specific diagnosis of patients with lysosomal storage diseases. 153 suspects originating from all regions of our country have been referred to our centre for further evaluation and final diagnosis. Initial work-up focused on clinical, pathological and radiological evaluation. Enzyme activity methods for the most common lysosomal storage diseases were standardised in our laboratory and indicated specific deficiencies in 63 patients (41.2%). Gaucher disease was the most prevalent lipidosis identified, as it was confirmed in 40 patients, belonging to 34 unrelated families. Other less prevalent sphingolipidoses were represented by GM1 gangliosidosis (4 patients), GM2 gangliosidosis (one patient), metachromatic leukodystrophy (one patient) and Fabry disease (6 patients).  Mucopolysaccharidoses and mucolipidoses were identified in 11 patients (3 mucopolysaccharidosis type I patients, 6 mucopolysaccharidosis type III B patients, one mucopolysaccharidosis type VII patient and one mucolipidosis type II patient). Plasma chitotriosidase activity, a marker of macrophage activation, was evaluated as a biochemical method for long-term monitoring of patients with Gaucher disease. Our experience suggests that biochemical methods for lysosomal enzyme testing may be the key step in the accurate diagnosis of these patients.

Keywords

Lysosomal storage diseases, Gaucher disease, Enzyme activity.