Abstract

Objective: The accurate diagnosis of neurodegenerative disease frequently rests on neuropsychological data, although more recently there has been an increased emphasis on the inclusion of neuroimaging and fluid biomarkers. Despite our knowledge about neurodegenerative disease, in the case of frontotemporal dementias, autopsy data expose the misdiagnosis rate of specialized memory centers as being around 20%. The case presented here highlights some of the diagnostic complexities in differentiating between behavioral variant frontotemporal dementia (bvFTD) and Alzheimer's disease. Method: Mr. B is a 59 year old, right handed French Caucasian sommelier, who presented to neurology after his wife became concerned about some changes in behavior and a slip in his competence at work. Mr. B himself complains of a stutter. These symptoms began about 2 years ago and appear to be worsening. Neurological examination demonstrated gegenhalten and restriction in upward gaze. MRI showed bilateral temporal polar atrophy. CSF analysis has been inconsistent. The referring neurologist asked if the cognitive profile was supportive of his initial suspicion of bvFTD. Results: On testing, he demonstrated flat learning and no recall of verbal information, in addition to other memory deficits and impairment on tests of attention and executive function. Conclusion(s): This case seemed from the history and neurological evaluation to be typical of bvFTD, but the neuropsychological profile, and later CSF findings suggest that frontal variant Alzheimer's disease could be a diagnostic consideration.