EAST syndrome

EAST syndrome, also known as SeSAME syndrome (Seizures, Sensorineural deafness, Ataxia, Mental retardation, and Electrolyte imbalance), is a rare autosomal recessive disorder caused by mutations in the KCNJ10 gene, which encodes the inwardly rectifying potassium channel Kir4.1. This channel plays critical roles in the brain, inner ear, and kidney, and its dysfunction leads to the characteristic multi-system features of the condition. The acronym EAST stands for Epilepsy, Ataxia, Sensorineural deafness, and Tubulopathy (renal salt wasting). The disease typically presents in infancy or early childhood with seizures (often generalized tonic-clonic), cerebellar ataxia causing difficulties with balance and coordination, and sensorineural hearing loss of variable severity. The renal tubulopathy resembles a Gitelman-like syndrome, characterized by hypokalemia, metabolic alkalosis, hypomagnesemia, and salt wasting. Affected individuals may also experience developmental delay and intellectual disability of varying degrees. The neurological features, particularly ataxia, tend to be progressive or persistent throughout life. Treatment is currently symptomatic and supportive. Seizures are managed with antiepileptic medications, though they may become less frequent with age in some patients. Electrolyte imbalances require ongoing oral supplementation with potassium and magnesium. Hearing aids or cochlear implants may be considered for hearing loss. Physical therapy and educational support are important components of management. There is no curative therapy available at present, and lifelong monitoring of renal electrolyte status is essential.

Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.

Common questions about EAST syndrome