Clinical heterogeneity in Hallervorden-Spatz syndrome: a clinicoradiological study in 13 patients from South India.

Hallervorden-Spatz syndrome (HSS) is a rare autosomal recessive neurodegenerative disorder of childhood. Thirteen patients with this syndrome seen over a period of 7 years were reviewed. Two distinct groups were identified. The early onset childhood group had uniform presentation with developmental delay, recurrent falls, gait abnormalities, cognitive deterioration and dystonia. This group was also characterised by familial incidence, retinal involvement and absence of behavioural problems. Late onset group, included patients with different presentations such as behavioural changes, optic atrophy and dystonia. Consanguinity was prominent in this study, being present in 61.5% patients. MRI (n=11) showed pallidal hyperintensity on T1-weighted images and hypointensity or 'eye of the tiger' sign on T2-weighted images. Two patients had acanthocytes in peripheral blood smear. This study emphasizes the phenotypic heterogeneity in HSS and as well brings out the common features shared by patients with early onset disease.