Posttraumatic premature Alzheimer's disease. Neuropathologic findings and pathogenetic considerations.

Dementia following head trauma is generally attributed to contusional injury or its complications. Dementia pugilistica and rare cases of classic Alzheimer's disease (AD) following head injury suggest that trauma may also play a provocative role in neurofibrillary change. The ages and clinical descriptions, however, allow other interpretations. A 38-year-old man died 16 years after substantial recovery from a single episode of severe head trauma. Pathologic study indicated that the clinical deterioration was due to classic AD. Ultrastructural evaluation demonstrated both paired helical and straight filaments in cortical neurons.