Related Experiment Videos
Frontotemporal dementia: one disease, or many?: probably one, possibly two
1Cognitive Neurology, Department of Psychology, Social Science Centre, SSC 7418, University of Western Ontario, London, Ontario. andrew.kertesz@sjhc.london.on.ca
Alzheimer Disease and Associated Disorders
|December 1, 2005
Summary
Frontotemporal dementia (FTD) is a clinical syndrome with diverse presentations and pathological subtypes. Evidence suggests tau-positive and tau-negative pathologies represent a spectrum, not distinct diseases.
Area of Science:
- Neuroscience
- Neuropathology
Background:
- Frontotemporal dementia (FTD) presents clinically with distinct subtypes, including behavioral variant FTD, progressive aphasia, semantic dementia, corticobasal degeneration, and progressive supranuclear palsy.
- FTD pathology is increasingly viewed as a spectrum, despite recognized histological variations.
Observation:
- Over half of FTD pathologies exhibit ubiquitin-positive, tau-negative inclusions, frequently observed in Amyotrophic Lateral Sclerosis (ALS).
- A clinical dichotomy correlates with pathological subtypes: tau-negative FTD (behavioral variant, semantic dementia) and tau-positive FTD (progressive aphasia, corticobasal degeneration/PSP).
Findings:
- Pathological and biochemical classifications of FTD can be dichotomized into tau-positive and tau-negative categories.
- Genetics of tau-positive FTD are linked to tau mutations, while tau-negative FTD genetics remain largely uncharacterized, though some cases link to chromosome 17.
Implications:
- The significant clinical and pathological overlap between FTD subtypes challenges their classification as separate diseases.
- Understanding FTD as a spectrum, encompassing both tau-positive and tau-negative pathologies, is crucial for accurate diagnosis and therapeutic development.