Infant with Type A Niemann Pick Disease and Undetectable Niemann Pick Cells in Bone Marrow.

Bone marrow aspiration is the preliminary investigation in Niemann Pick disease type A when enzyme assays and mutation studies are unavailable. We report an infant with typical phenotype and enzyme deficiency, but undetectable Niemann Pick cells in the bone marrow. A new mutation R542X in SMPD gene was also detected.