F16 Clinical profile of juvenile huntington disease: an indian cohort

Abstract

Juvenile Huntington disease (JHD) is a distinct phenotype of Huntington disease (HD) with onset before 20 years age and/or CAG repeats >/=60 and is marked by akinetic/hypokinetic manifestations as compared to predominant hyperkinesias in adult-onset HD (AOHD). We briefly describe the profile of JHD in an Indian cohort (n=10) with detailed history of 5 patients. The CAG repeats of their upper alleles ranged from 59–113 (mean 76) and age at onset from 5–20 years (mean 12.7 years). All patients inherited mutant allele from father except one patient who inherited it from mother. Anticipation was highest in a patient with an increase of 70 CAG repeats from parent to child. 7/10 (70%) patients were a/hypokinetic with prominent dystonias and rigidity where as 30% had chorea as the presenting complaint. One child had uncontrolled seizures with myoclonic spasms and generalized dystonia. Eye movement abnormalities were common (8/10) and characteristic as compared to AOHD. Three patients had severe oculomotor apraxia. Two patients had marked cognitive decline while others had milder cognitive impairments. Behavioural abnormalities included irritability, apathy, poor self-care, stubbornness with varying severities. One patient presented with depression and past history of suicidal attempts. In summary, the phenotypes of JHD are more heterogeneous than it is believed to be and needs special attention. We aim to highlight the shared and unique clinical features across JHD patients.