Ketogenic diet for alternating hemiplegia of childhood: Case report and literature review

Rationale: Alternating hemiplegia of childhood (AHC) is a serious and rare neurological disease caused by mutations in the ATP1A3 gene. Patients mainly present with paroxysmal hemiplegia, dystonia, abnormal eye movement, dyspnea, and other autonomic neurological phenomena. Patient concerns: Here, we described a patient who initially presented with abnormal eye movements, followed by the subsequent development of seizures and alternating hemiplegia. Diagnoses: Whole exome sequencing identified a heterozygous variant in the ATP1A3 gene: c.2443G > A (p.Glu815Lys). Thus, the patient was diagnosed with AHC. Interventions: Flunarizine combined with oxcarbazepine did not improve clinical symptoms. Outcomes: Interestingly, typical AHC paroxysmal episodes gradually improved after starting the ketogenic diet, but the seizures did not resolve. Long-term follow-up shows a global improvement in neurological development. Lessons: Our case reinforces the role of the ketogenic diet as a novel therapeutic option for AHC. However, further specific confirmatory tests are necessary.