Introduction ATP1A3 variants have been described in multiple neurological syndromes with newly emerging phenotypes, such as the recently described fever-induced paroxysmal muscle weakness and encephalopathy (FIPWE) and others. We hereby describe 3 cases of ATP1A3 mutations with three different phenotypic presentations and their management.

Methods: Case series.

Results: Patient 1: This 18-month-old male; presented with fever induced episodes encephalopathy, developmental regression, and seizures. He showed limited response to Oxcarbazepine. The episodes were less severe with aggressive fever management. He is now developmentally delayed with hypotonia. Patient 2: aged 3 years; this boy presented with recurrent episodic right-sided hemiplegia. He had neonatal seizures and delayed motor development. His symptoms resolved with the commencement of oxcarbazepine. His episodes resolved with an improvement in his cognition. Patient 3: This girl presented at the age of 14 months with episodes of alternating hemiplegia and abnormal eye movements. She also had focal seizures, hypotonia and developmental delay. She minimally responded to oxcarbazepine. Flunarizine fully controlled her hemiplegia and seizures. She is now 4 years old and is attaining developmental progress but remains delayed.

Conclusion: With the expanding spectrum of ATP1A3-related disorders, the diagnosis should be considered in patients with episodic febrile encephalopathy and patients with recurrent transient hemiparesis. In addition to the described role of flunarizine in ATP1A3 related disorders, oxcarbazepine may play a positive role in the management of patients with ATP1A3 mutations through its sodium blocking properties or via some other unknown mechanisms.

Saja Tahir
Al Jalila Children's Specialty Hospital
United Arab Emirates

Ali Nasreldien
Al Jalila Children's Specialty Hospital
United Arab Emirates

Mohamed Babiker
Al Jalila Children's Specialty Hospital
United Arab Emirates