We report a familial case of Niemann-Pick disease type C which lasted until adulthood, and which had the characteristic deficiency in cholesterol esterification from exogenous cholesterol. A review of the literature was performed concerning cases which were seen in adults and were characterized biochemically. This study showed the frequency of supranuclear ophthalmoplegia affecting essentially vertical movements and convergence and of lipid-laden cells in bone marrow which are often sea-blue histiocytes.