Kufor-Rakeb syndrome: a cohort-based clinical, imaging and genetic profile

BACKGROUND: Kufor-Rakeb syndrome (KRS), a autosomal recessive disease has phenotypic and genotypic variability. OBJECTIVE: Detailed description of the clinical, imaging, genetic profile of KRS and comparison of Indian cohort with Asian, Middle east and European cohort. METHODS: Report of two patients of KRS and review of reported cases of KRS since 2006 from Indian, Asian, Middle east and European cohorts. RESULTS: There were 9 cases in Indian cohort, 23 in Asian/Middle East and 37 in European cohort. Patients in the Indian cohorts had earlier age at presentation but age at onset of disease was similar in all cohorts. The median duration of disease was lower in the Indian cohort. Levodopa- responsive parkinsonism was commonest presentation in all cohorts. Dementia, myoclonus was less common in Indian cohort, dyskinesia, dystonia in Asian/ middle east cohort, and dystonia in the European cohort. Cerebral/cerebellar atrophy was noted in all cohorts (60.9%). Homozygous/compound heterozygous ATP13A2 gene variants were associated with the dementia-parkinsonism with dystonia, gaze palsy, myoclonus and heterozygous variants with early-onset levodopa responsive parkinsonism. CONCLUSION: KRS presents as dementia-parkinsonism with dystonia, gaze palsy, myoclonus, psychiatric disturbances due to homozygous/compound heterozygous ATP13A2 gene variants or as early-onset levodopa responsive parkinsonism due to heterozygous variants. There exists phenotypic variability among the cohorts.