Application of a comprehensive protocol for the identification of Gaucher disease in Brazil

Gaucher disease (GD) is a sphingolipidosis caused by a genetic defect that leads to glucocerebrosidase (beta-glucosidase) deficiency. Between January 1982 and October 2003, 1,081 blood samples from patients suspected of having GD were referred for biochemical analysis. The activities of the enzymes beta-glucosidase (beta-glu) and chitotriosidase (CT) were measured in these samples. Among the 412 diagnosed cases of GD (38.1%), the great majority were GD type 1. The Brazilian regions with the greatest concentration of these patients were the Southeast, South, and Northeast. The mean age of patients at diagnosis was 19 years. The activity of beta-glu in patients with GD was, on average, 10.7% of that of normal individuals. CT was, on average, 269 times more elevated in this group of patients. Among the 669 cases with no confirmation of GD, there were patients with Niemann-Pick disease types A, B, or C (44 cases), possible heterozygotes for GD (59 cases), patients with other lysosomal storage diseases (LSDs) (19 cases) or with other inborn errors of metabolism (3 cases). In 508 cases, no metabolic disorder was found. This study shows that the biochemical protocol employed was effective for the detection of GD, a disease that is reasonably frequent in Brazil.