A severely retarded infant is noted to have hepatosplenomegaly and a cherry-red spot in the macula. Of the following, which is most likely the cause of these findings?

Niemann-Pick Disease is an autosomal recessive disorder that results from defects in acid sphingomyelinase. Types A and B are distinguished by an early age of onset and progressive CNS disease in type A. Type A typically has onset in the first 6 months, with rapidly progressive CNS deterioration, spasticity, failure to thrive, and massive hepatosplenomegaly.A cherry-red spot in the macula is noted in about 30% of patients. Tay-Sach's Disease (defective hexosaminidase A) is associated with psychomotor retardation and a cherry-red spot, but no hepatosplenomegaly. Macular Degeneration and a cherry-red spot are NOT pa of the clinical picture of Gaucher's disease, metachromatic leukodystrophy, or globoid-cell leukodystrophy. Ref: Hopkin R., Grabowski G.A. (2012). Chapter 361. Lysosomal Storage Diseases. In D.L. Longo, A.S. Fauci, D.L. Kasper, S.L. Hauser, J.L. Jameson, J. Loscalzo (Eds), Harrison's Principles of Internal Medicine, 18e.