Résumé
Niemann Pick disease type B is a rare autosomal recessive lipid storage disorder, characterized by a partial deficiency of sphingomyelinase We report two cases one in a boy aged of 3 years old, and the other a 18-month-old girl. All of them have related parents. The circumstances of discovery were a hepato-splenomegaly without neurological signs and interstitial syndrome on chest radiograph. Laboratory tests showed a moderate hepatic cytolysis and microcytic hypochromic anemia. The bone marrow showed many cells overload Niemann-Pick type. Diagnostic confirmation was achieved by a decrease in cell lysosomal enzyme activity. It is a lysosomal disease characterized by visceral abnomality with preserved nervous system function. The current treatment of Niemann Pick disease is purely symptomatic awaiting the use of enzymatic replacement therapy