Early detection of fronto-temporal degeneration by clinical evaluation

Although Alzheimer's Disease (AD) is the most common degenerative dementia, other neuropathological processes are well known to cause dementia syndromes. Fronto-temporal degeneration (FTD) is one such entity, and often produces a clinical presentation distinct from that of AD. Some FTD cases are shown at autopsy to be classic Pick's Disease, but others defy precise classification at this point because they lack characteristic Pick bodies. We describe a case of putative FTD in a 54-year-old man with personality change and complete Klüver-Bucy syndrome. Neuropsychological evaluation disclosed evidence of extensive frontal system dysfunction, with lesser problems in memory, language, and visuospatial skills. Magnetic resonance imaging studies after 17 months of the illness were largely nonspecific, but a follow-up scan 16 months later revealed bifrontal and bitemporal atrophy with ventricular enlargement. Neuromorphometric analysis suggested an increase in cortical atrophy and ventricular dilation over time. This case emphasizes the value of careful clinical evaluation in unusual non-AD degenerative dementias and suggests that neuroimaging studies may be less sensitive in the early diagnosis of such cases.