AAN 2013

JUVENILE HUNTINGTON´S DISEASE IN AN ARGENTINEAN POPULATION

 Virginia Parisi; Ana Sanguinetti; Gabriel Persi; Jose Etcheverry; Emilia Gatto

Background and purposes: Huntington´s disease (HD) is an autosomal dominant disorder characterized by motor, cognitive and psychiatric manifestations. It is caused by an abnormal CAG expansion, in the coding region of IT15 gene at chromosome 4p16.3. Onset  before the age of 20 years  is classified as Juvenile onset HD (JHD), which can be further divided into childhood (≤10 years) and adolescent (11-20 years) onset. JHD prevalence ranges from 1% to 15%.  Parkinsonian-akinetic syndrome and dystonia are the dominant motor features in JHD. Additional neurological features include: cerebellar signs, epilepsy, myoclonus, gait disorders and spasticity. Behavioural problems, cognitive decline are also common in JHD.  Given that ethnicity background might play a role in modulating the phenotype, we conducted an observational study to describe clinical and genetic characteristics of a series of JHD patients from a center in Argentina.
Patients and methods: The study was approved by institutional review board. JHD patients were identified from our database. Inclusion criteria were: disease onset ≤ 20 years and clinical diagnosis of HD with molecular confirmation or parent with clinical and molecular clinical diagnosis of HD. Demographic, epidemiological, clinical and genetic data were analyzed.
Results:  60 HD patients were identified. JHD was individualized in 6 women and 5 men (18%), they had 40-80 CAG repeats, and mean age at onset 12.9 years. Paternal inheritance was reported in 7/10 cases. Seizures occurred in 1 case, in 3 Westphal variant and behavioral disorders were present in all cases. MRI showed caudate atrophy and putaminal hyperintensity on T2 in 4 patients. Childhood onset (≤10 years) occurred in 3 patients (5%), with  a range of 43-80.nCAG repeats.
Conclusion: This is the first reported series of JHD from Argentina. Beside the small sample, the present study shows a higher prevalence than previous studies from other countries. Meanwhile, seizures were less reported than other international series.