Autosomal dominant Kufs' disease: a cause of early onset dementia.

Kufs' disease is the rare, adult-onset form of the neuronal ceroid-lipofuscinoses (NCL). Two clinical Kufs' phenotypes have been described, one featuring generalized tonic-clonic seizures and the other characterized by dementia. Autosomal dominant inheritance of Kufs' disease has been reported for only two families. The genetic and molecular defects underlying Kufs' disease are unknown. We report a third family with apparent autosomal dominant Kufs' disease in a family of English ancestry. Ten individuals (five men, five women) have been affected over five generations. Age of onset typically is in the fourth decade of life and is heralded by seizures. Clinical and neuropsychological assessments in several affected individuals, however, confirm the presence of dementia and follow-up evaluations suggest that dementia is the primary disabling feature of the illness. Motor abnormalities also are frequent. Neuropathological examination (three cases) documents the presence of neuronal lipopigment accumulation consistent with NCL. The combination of dementia and seizures in this and two other reported families with autosomal dominant Kufs' disease suggest that this entity represents a distinctive clinicopathological entity. Dementia is prominent but is almost always associated with generalized seizures and motoric disturbances early in the disease course. Kufs' disease should be considered in the differential diagnosis of early onset, atypical dementia.