[Two cases of familial idiopathic basal ganglia calcifications (BCG) with non-symptomatic family members].

We reported two families each propositus of which exhibited extrapyramidal signs and dementia with bilateral basal ganglia calcifications (BGC), while some of the other non-symptomatic family members showed BCG on brain CT by further examinations. Family 1) A 49-year-old woman was normal until her mid 40s when her memory began to fail. At age 40, dementia, finger-tremor and rigidity were observed and with brain CT and Magnetic Resonance Imaging, BCG and dentate calcifications were found. Her two daughters (20 years old and 26 years old) were free of any neuropsychiatric symptoms, but with CT examinations disclosed BCG. Family 2) A 40-year-old man. His symptoms started at 33 years old. He noticed gradually increasing finger-tremor, rigidity and dysarthria. At 40 years he showed mild dementia and BCG on Brain CT. His mother (64 years old) was non-symptomatic but CT showed that she had BCG. In the two families the calcium, phosphorous and parathyroid hormone levels, and Ellsworth-Howard test were normal. Other specific etiology including infections and somatic abnormalities was not discovered. Familial idiopathic basal ganglia calcification was considered to be rare. But the main purpose of this report is to point out that we must pay attention to the possibility of BCG of non-symptomatic family members if one showed dementia and extrapyramidal signs, and BCG on Brain CT in middle age.