Frontotemporal dementia is a dementia syndrome with diverse clinical characteristics. Based upon clinical parameters and single photon emission computed tomography, we identified 47 frontotemporal dementia subjects. In 10 of these 47 the primary site of brain dysfunction was anterior temporal and orbital-frontal with other frontal regions relatively spared. In this temporal lobe variant (TLV) of frontotemporal dementia, five of the subjects had more severe left-sided, and five had more right-sided, hypoperfusion. The clinical, neuropsychological and neuropsychiatric features of predominantly left-sided (LTLV) and right-sided (RTLV) TLV subjects are discussed and contrasted with more frontal presentations of frontotemporal dementia. In LTLV, aphasia was usually the first and most severe clinical abnormality RTLV patients presented with behavioural disorders characterized by irritability, impulsiveness, bizarre alterations in dress, limited and fixed ideas, decreased facial expression and increased visual alertness. These findings suggest that: (i) frontotemporal dementia is clinically heterogeneous with bitemporal and inferior frontal lobe dysfunction contributing to the clinical presentation; (ii) behavioural disturbance and aphasia are the most prominent features of predominantly temporal subtypes of frontotemporal dementia; (iii) the right and left anterior temporal regions may mediate different behavioural functions. The results of this study suggests that TLV offers a valuable source of information concerning the behavioural disorders seen with combined anterior temporal and inferior frontal lobe dysfunction.

Human herpesvirus 6 (HHV-6), the etiologic agent of roseola in young children, has been reported to be detectable in the brain of many neurologically normal adults, although regional localization to plaques of multiple sclerosis has also been demonstrated. Large amounts of this virus were present in multifocal demyelinating white matter lesions of fulminant encephalomyelitis with seizures in a 21-year-old woman with normal immune parameters. Brain biopsy after 3 weeks of neurologic deterioration revealed a viral etiology by light and electron microscopy; the virus was identified as HHV-6 by immunohistochemistry and by polymerase chain reaction (PCR) amplification in biopsy and autopsy specimens.

The Mini-Mental State Exam (MMSE) is a widely used cognitive screening measure. The purpose of the present study was to assess how 5 specific clusters of MMSE items (i.e., subscores) correlate with and predict specific areas of daily functioning in patients with dementia. Sixty-one patients with varied forms of dementia were administered the MMSE and an observation-based daily functional test (the Direct Assessment of Functional Status; DAFS). The results revealed that the orientation and attention subscores of the MMSE correlated most significantly with nearly all of the functional domains. The MMSE language items correlated with all but the DAFS shopping and time orientation tasks, while the MMSE recall items correlated with the DAFS time orientation and shopping tasks. Stepwise regression analyses found that among the MMSE subscores, orientation was the single, best independent predictor of most of the DAFS functional domains, with language, attention and recall subscores accounting for additional variance on DAFS functional tasks. These results indicate that the MMSE is not only a good cognitive screening tool, but its specific subsores can predict functional disabilities in patients with dementia.