AUTOPSY-PROVEN PROGRESSIVE SUPRANUCLEAR PALSY IN 2 SIBLINGS

Progressive supranuclear palsy (PSP) is a neurodegenerative disorder t hat is generally considered to be nonfamilial. We report a brother and sister with clinical and pathologic findings characteristic of PSP. B oth developed parkinsonism in the eighth decade of life and within 5 y ears exhibited severe postural instability, bradykinesia, rigidity, dy stonia, dysarthria, dysphagia, urinary incontinence, pseudobulbar pals y, and supranuclear oculomotor dysfunction but no tremor. Neither resp onded to levodopa and/or carbidopa. Their mother and, possibly, matern al grandfather reportedly suffered from a parkinsonian syndrome. Essen tial tremor occurred in the siblings' father and in two of the brother 's three children. Autopsy in the brother at age 81 years and sister a t age 79 years revealed changes typical of PSP with atrophy and neurof ibrillary tangles in the globus pallidus, subthalamic nucleus, and ros tral tegmental brainstem. No Lewy bodies were present. These cases are the first pair of relatives reported with autopsy confirmation of PSP in both and raise the question of genetic predisposition to PSP.