A one year old boy presented with hepatosplenomegaly and delayed milestones. The liver biopsy and bone marrow biopsy revealed presence of histiocytes with PAS-positive Diastase-resistant material in the cytoplasm. Electron-microscopic examination of these histiocytes is most likely to reveal the presence of -

Ans. is 'c' i.e., Parallel rays of tubular structure in lysosomeo Look at the clinical feature of the child.a) One year old boyb) Hepatosplenomegalyc) Delayed milestoneso The above mentioned clinical features and likely presence of Glycolipids, Glycoprotein (PAS positive diastase resistant material) indicate some lysosomal storage disorder.o Most probably it is a case of Niemann's picks diseaseo See the clinical features of Niemann Picks disease. Presence of hepatosplenomegaly Mental retardation Delayed growtho The pathological feature of Niemann's Picks disease is characterized by the presence of large foam cells in bone marrow, liver and spleen. Electron microscopy will show plemorphic inclusion, of lipids in lysosomes. These lipids are enclosed in concentric or parallel lamellae.o All the above mentioned features can be seen in Gaucher's disease too but the electron microscopy in Gaucher's is characterized by the presence of elongated distended lysosomes containing the stored lipids in stacks of bilayers.