Frontal dementia: a cortical dementia under the mantle of Alzheimer's disease
BALOYANNIS SJ

Alzheimer's disease is a neurodegenerative disorder clinically characterized by progressive cognitive decline and personality changes in senium and presenium. Although Alzheimer's disease is the commonest cause of dementia followed by vascular dementia, there are some other, much rarer causes of cognitive impairment, which are covered under the phenomenological mantle of Alzheimer's disease, due to its clinical heterogeneity. Among them the frontal dementia might be considered in cases of progressive loss of fluency in speech, eventually resulting in aphasia or associated frequently with early loss of insight and many forms of inappropriate behavior.

In the present study we describe three cases of frontal dementia, underlying the clinical criteria that might be helpful in the early differential distinction of the disease from the various subtypes of Alzheimer's disease. Hyperphorsphorylation of the isoforms of tau (τ) protein, a microtubule associatein, which plays an important role in the pathogenetic mechanisms of Alzheimer's disease, is mainly involved in the pathogenesis of frontal dementia, since it is the main protein constituent of Pick's bodies and segregates to different neuronal compartment, affecting seriously the cytoskeleton of the nerve and glial cells.