Unusually rapid and severe cognitive deterioration after mild traumatic brain injury

A 56-year-old man (AB) presented with dramatic cognitive deterioration following a mild traumatic brain injury. There was no indication of severe brain injury or significant anoxic encephalopathy. Detailed history indicated no significant pre-morbid cognitive deficits. His pre-injury psychosocial and occupational functioning was intact. Cognition functioning was impaired immediately post-injury and remained impaired. Neuropsychological examination at 8 months post-injury showed severe cognitive deficits. The cognitive profile was consistent with Alzheimer's disease. MRI at 1-year post-injury showed minor ischaemic changes not consistent with hypoxic injury and insufficient to explain his cognitive problems. Early SPECT was consistent with a diagnosis of Alzheimer's disease and a repeat SPECT showed a significant deterioration in an Alzheimer pattern. AB was seen for detailed serial neuropsychological examination over a 3-year period, which revealed clear evidence of cognitive deterioration consistent with Alzheimer's disease. AB is presented as an unusual case of rapid progressive AD following a mild head injury.