Pb2560: lysosomal storage diseases: guacher’s disease and niemanpick ‘s diseases: study of clinical, cytological and enzymatic aspects

Topic: 28. Enzymopathies, membranopathies and other anemias Background: Lysosomal storage diseases (LSD) comprise a large group of rare inherited disorders (1 in every 7000 births) more than 40 LSD are known and classified based on biological and clinical suspects such as Gaucher ‘s disease and Nieman pick’s disease. These are lysosomal overload diseases characterized by a deficiency in β-glucocerebrosidase (BGS) responsible for a multisystem disease with varied clinical symptoms. Aims: The aim of this study was to study the concordance between the cytological aspect in the myelogram and the enzymatic essay. Methods: This is a retrospective descriptive study conducted in the hematology laboratory and biochemistry laboratory in collaboration with clinical hematology service at Farhat Hached Hospital in Sousse Tunisia. The patients included were those who presented with suspicion of having Gaucher ‘s disease or Nieman Pick ‘s disease between January 2013 and December 2022. Results: Our study included 28 patients in total. The median age was 22 years (range 1 and 52 years). The sex ratio (M/F) was 2.1. The circumstances of discovery were dominated by hepatosplenomegaly in 71.4 % of cases. A family history was also noted in 42% of cases. The cytopenia on the haemogram showed anaemia in 67.9% of cases, isolated in 15% of cases. A bicytopenia was observed in 85% of cases, dominated by the association of anaemia with thrombopenia in 81%. Myelogram showed the presence of Niemann Pick cells in 35% of cases while Gaucher cells were present in 53% of cases. The enzymatic assay was done for only 7 patients (Confirming the diagnosis in 4 cases). The median of BGS activity assay was 1.14 µkat/Kg of protein. The hexosaminidases assay was normal (300-850 µkat/Kg of protein) in 95 % of cases. the ratio BGS + taurocholic acid/ hexosaminidase was under the normal rage (0.83-1.45) in 70% of cases with a median of 0.5 (*100). Summary/Conclusion: The laboratory diagnosis of Gaucher’S disease and Niemann Pick ‘s disease should always be based on the enzymatic assay of BGS activity but also we can’t neglige the importance of the cytological aspect with the detection of storage cells in the myelogram. Keywords: Gaucher disease, Lysosomal storage disease