Lysosomal storage disorders: Morphologic appraisal in Indian population

Background: Lysosomal storage disorders (LSDs) comprise a group of at least 50 distinct genetic diseases, each one resulting from the deficiency of a particular lysosomal enzyme involved in metabolism. We attempt to study and further subclassify pediatric LSDs into Gaucher's and non-Gaucher's category based on the morphologic variables seen in the bone marrow aspiration smears and trephine biopsy sections. Materials and Methods: Pediatric (<12 years age) cases of LSDs diagnosed by bone marrow aspiration and trephine biopsy specimens, in the last 12 years period, were retrieved. The archival material and the relevant clinical as well as hematologic parameters were reviewed. Results: From January 1997 to December 2008, 55 cases were diagnosed as LSDs. Based on bone marrow morphology, 56% (n = 31) cases were diagnosed as non-Gaucher's and the remaining 44% (n = 24) cases as Gaucher's disease, the ratio being 1.29:1. Anemia and thrombocytopenia were more commonly observed in Gaucher's disease (91.67 and 62.5%) as compared to non-Gaucher's group (74.19 and 19.35%). Neurologic symptoms and signs were more frequently present in non-Gaucher's cases (45.16%) as compared to Gaucher's group (29.17%). Conclusion: LSDs can be classified into Gaucher's and non-Gaucher's subtypes based on the characteristic cytomorphology of the storage cells in Giemsa-stained bone marrow aspiration smears and on hematoxylin and eosin-stained trephine biopsy sections. This approach would be fairly adequate for therapeutic and prognostic purposes in resource-constrained settings, where enzyme studies and mutational analysis may not be easily available.