FTD with parkinsonism linked to chromosome 17 (FTDP-17)
by André Delacourte
Fronto-temporal clinical signs associated with Parkinsonism features. The Parkinsonian features are related to movement disorders such as rigidity, reduced speed and uncontrolled movemements, including those of the eye (supranuclear palsy).
Symptoms and course
Clinical presentation is extremely variable, according to the type of mutation on tau gene, and heterogeneous inside a same family. Patients may have slowly progressive behavioural changes, language disturbances, and/or extrapyramidal signs. Some have with rigidity, bradykinesia, supranuclear palsy and saccadic eye movement disorders. Symptoms usually start between 40 and 60 years of age, but may occur earlier or later. Disease duration is usually between five and ten years, but occasionally may be up to 20-30 years. The disease progresses over a few years into a profound dementia with mutism.
FTDP-17 is extremely rare, but frequent in patients with FTD and a familial history (Rosso et al 2002).
Clinical (to observe frontotemporal and parkinsoninan signs) and MRI (to observe atrophy of frontotemporal regions and to exclude other pathologies such as vascular pathology) (FTD phenotype). Familial cluster. Genetic test for the tau gene mutations.
Causes and risk factors
FTD is mainly due to abnormalities of tau gene or tau protein.
Care and treatment
As yet there is no cure for fronto-temporal dementia and the progression of the condition cannot be slowed. Drugs that are designed for the treatment of Alzheimer's disease, such as Aricept and Exelon, may make symptoms worse and increase aggression. Symptomatic for disinhibition and behavioural problems. Antidepressants for apathy. Trazodone for agitation. No prevention.
Ongoing research / clinical trials
These mutations have generated the concept of “tauopathies”, since the cause of the disease is tau mutations. Many other neurodegenerative disorders have also tau abnormalities.
The Association for Frontotemporal Dementias
- Ingram, E. M. and M. G. Spillantini (2002). Tau gene mutations: dissecting the pathogenesis of FTDP-17. Trends Mol Med 8(12): 555-62.
- Lebert F, Stekke W, Hasenbroekx Ch, Pasquier F.Fronto-temporal dementia. A randomized, controlled trial with trazodone. Dem Cogn Disord. (in press)
- Rosso SM, van Herpen E, Deelen W, Kamphorst W, Severijnen LA, Willemsen R, Ravid R, Niermeijer MF, Dooijes D, Smith MJ, Goedert M, Heutink P, van Swieten JC (2002) A novel tau mutation, S320F, causes a tauopathy with inclusions similar to those in Pick's disease. Ann Neurol 51:373-6
Last Updated: vendredi 09 octobre 2009