Pick's disease and frontotemporal dementias: Emerging clinical and molecular concepts

BACKGROUND- Frontotemporal dementia (FTD) is a degenerative dementia that has increasingly captured the interest of behavioral neurologists, neuropsychologists, and molecular biologists. New developments in the areas of neurology and neuropsychology have helped lead to better recognition and treatment of patients with FTD. Additionally, discoveries in molecular biology are leading to an understanding of the molecular basis of this condition. REVIEW SUMMARY- The prevalence and risk factors for FTD are outlined, and new discoveries related to the genetics and neuropathology of FTD are noted. The clinical, neuropsychological, and neuroimaging features of FTD are described and methods for differentiating FTD from Alzheimer's disease are presented. The similarities and differences between FTD and other degenerative disorders including progressive supranuclear palsy, motor neuron disease, and corticobasal degeneration are described. Finally, treatments for FTD are discussed. CONCLUSION- FTD is a common cause for degenerative dementia in patients who are under the age of 65, and the clinical features are dictated by progressive loss of function in the anterior frontal and anterior temporal lobes. Many patients eventually develop Parkinsonism and motor neuron disease. The disorder can be highly asymmetric, affecting only the left or right frontal or temporal regions, and this asymmetry is responsible for differing clinical presentations. Mutations in tau protein have been found in families with inherited forms of this disorder, and the tau mutations seem to be responsible for the brain degeneration associated with FTD. Aggregations of abnormal tau also occur in progressive supranuclear palsy, and corticobasal degeneration and the clinical features of these disorders have many parallels with FTD. The most effective treatments for FTD now involve the use of antidepressants that work through the serotonin system.