[Hereditary cerebral hemorrhage. Dementia with cystatin C amyloidosis].

Nineteen cases of hereditary cystatin C amyloidosis with cerebral haemorrhage are described. The first haemorrhage occurred between the ages of 20 and 41 years and the period of survival varied from 10 days to 23 years after the first insult. Progressive dementia was a striking clinical symptom in 17 of the patients and in two cases dementia was the first sign. At the last examination severe dementia and pronounced pathological EEG were established in the majority of the patients. Infiltration of amyloid substance positive for anti-cystatin C was found in the proximity of the blood vessels and in their walls. Lesions in the cerebral microvascular system together with haemorrhages and infarcts caused thereby were considered to be an adequate explanation of the dementia in these patients. In view of the discovery of amyloid discharges in tissues outside the CNS it is adjudged more correct to use the name Hereditary Cystatin C Amyloidosis (HCCA).