Médecine moléculaire et génétique

Twenty-Five Years of Biochemical Diagnosis of Gaucher Disease: The Egyptian Experience

Abstract

Fateen EM and Abdallah ZY

Background: Gaucher disease is a rare multi-systemic metabolic disorder resulting from the deficiency in β-glucocerebrosidase enzyme, with consequent accumulation of glucocerebroside. Less than 15% of mean normal activity β-glucocerebrosidase in leukocytes is the gold standard for the diagnosis of Gaucher disease, which is supplemented by a massive elevation in chitotriosidase enzyme activity. We report here our experience in the biochemical diagnosis of Gaucher disease by showing the variability and the heterogeneity of the activity of enzymes over 25 years from 1993-2017, through referring 5128 clinically suspected Gaucher disease cases to our Biochemical Genetics Department, National Research Centre, as the main reference lab in Egypt for the diagnosis of Inherited Metabolic Disorders.

Methods: β-glucosidase enzyme activity and chitotriosidase were done to all referred cases. Sphinogmylinase activity was estimated for all cases with normal activity of β- glucosidase and moderate elevation of chitotriosidase.

Results: Out of the 5128 suspected cases, 881 (17%) had deficiency in β-glucocerebrosidase activity, accompanied with high chitotriosidase activity level, ranges (213-66700 μmol/l/h) and mean (7254.8 μmol/l/h). Zero chitotriosidase activity is found in 9 patients (1%) with low β-glucosidase. 451 cases were diagnosed as Niemann Pick patients (8.8%).

Discussion and Conclusion: Other biochemical markers are needed in addition to chitotriosidase enzyme for the diagnosis. Molecular testing was done in relatively small numbers and need to be available parallel with biochemical testing.