Successful screening for Gaucher disease in a high-prevalence population in tabuleirodo norte (Northeastern Brazil): A cross-sectional study

Abstract

Results: Screening with DBS-FP identified 135 subjects(18.2%) with GBA activity < 2.19 nmol/h/mL, 131 of whomremained in the study. In ten of these (7.6%), GBA activityin leukocytes was 2.6–5.5 nmol/h/mg protein. Subsequentmolecular analysis confirmed six cases of heterozygosityand four normals for GD. Conclusion: DBS-FP assay was shown to be an effectiveinitial GD-screening strategy for high-prevalence populationsin developing regions. Diagnosis could not be establishedfrom GBA activity in leukocytes alone, but requiredconfirmation with molecular analysis. Methods: Between 1 June 2007 and 31 May 2008, 740consented residents and descendants of traditional familiesfrom Tabuleiro do Norte were submitted to screening withDBS-FP. Subjects with GBA activity < 2.19 nmol/h/mLwere referred to the analysis of GBA and chitotriosidaseactivity in peripheral leukocytes and in plasma, respectively.Subjects at highest risk for GD (GBA activity in peripheralleukocytes < 5.6 nmol/h/mg protein) were referred to molecularanalysis to confirm diagnosis. Background: Gaucher disease (GD) is a hereditarylysosomal storage disorder characterized by the accumulationof glucosylceramide, mainly in the cells of thereticuloendothelial system, due to a deficiency of the enzymeacid b-glucosidase (GBA). Diagnosis is usually basedon measurement of GBA activity in peripheral leukocytes.The purpose of this study was to evaluate the ability ofscreening for GBA and chitotriosidase activity using driedblood spots on filter paper (DBS-FP) to identify individualsat high risk for GD in high-risk populations such as that ofTabuleiro do Norte, a small town in Northeastern Brazil.