[Niemann-Pick disease in a boy 1 year and 10 months old]

A typical case of Niemann-Pick disease in a 22-month boy is presented. The disease was associated with a CNS lesion, as well as with the impairment of macrophagal-histiocytic system. The study of native material in the polarized light with subsequent confirmation by histochemical methods is considered as a method of choice for diagnosis of lingering diseases beginning in the postnatal period and with a suspicion of thesaurismosis, sphingomyelinosis, in particular.