Dementia as the most common presentation of cortical-basal ganglionic degeneration.

OBJECTIVE: To evaluate the clinical presentations and dominant symptoms of patients with postmortem proven cortical-basal ganglionic degeneration (CBGD) from one neuropathology center.
BACKGROUND: CBGD is a rare but increasingly recognized condition with clinical and pathologic features that continue to evolve. Attempts have been made to develop clinical criteria to enhance the specificity of diagnosis, but it is not clear what proportion of patients harboring CBGD disease present in the "classical" fashion versus other presentations. Previous large-case series that emphasize a parietal/perceptual-motor presentation may be biased because the cases mainly originate from movement disorder centers.
METHODS: Thirteen cases of pathologically confirmed CBGD with sufficient clinical data were identified from a single neuropathology center between 1981 and 1996.
RESULTS: Before death, only 4 of the 13 patients had a clinical diagnosis of CBGD, 6 had a clinical diagnosis of Alzheimer's disease (AD), 1 had AD and parkinsonism, and 2 had an atypical dementia of the frontotemporal type. Nine of 13 cases had early dementia.
CONCLUSIONS: Dementia was the most common presentation of CBGD in this study. Despite the best efforts to define criteria to enhance the specificity of a diagnosis of CBGD, it is becoming clear that the clinical syndrome that accompanies this disease is quite varied. Unfortunately, patients fulfilling classical diagnostic criteria may represent a minority of those with this pathologic diagnosis.