NOVEL ATP1A3 MUTATION IN A SPORADIC RDP PATIENT WITH MINIMAL BENEFIT FROM DEEP BRAIN STIMULATION

Rapid onset dystonia-parkinsonism (RDP) is a rare, autosomal dominantly inherited movement disorder, characterized by abrupt or subacute onset of both dystonic symptoms and parkinsonism with prominent bulbar involvement.1,2 Onset usually occurs in late adolescence or early adulthood and may be triggered by stresses such as physical exercise, extreme heat, or emotionally traumatic events. In one sporadic patient, bilateral deep brain stimulation (DBS) of the globus pallidus internus (GPi) failed to alleviate symptoms.3 Recently, six missense mutations in highly conserved regions of the ATP1A3 gene, encoding a Na+/K+-ATPase, have been identified.4 ### Case report. A 12-year-old boy experienced acute onset of severe dysphagia and dysarthria within hours after physical overexertion. Within weeks, severe generalized dystonia of all four limbs evolved, resulting in an inability to walk unassisted. Over the next 2 years, speech and swallowing improved considerably, but limb dystonia only slightly, so he was again able to walk independently. Extensive investigations including cranial MRI, DAT scan, CSF studies, EEG, and laboratory investigations …