Effect of Acetazolamide in a Child with CACNA1A Channelopathy, Refractory Seizures, and ADHD

Variants in the calcium voltage-gated channel subunit alpha1 A (CACNA1A) gene, located on chromosome 19p13, are implicated in diverse neurological syndromes, including epileptic encephalopathy, episodic ataxia type 2 (EA2), spinocerebellar ataxia type 6 (SCA6), and familial hemiplegic migraine type 1 (FHM1) [1].Often, calcium channelopathies are comorbid with behavioral disorders such as autism spectrum disorder and attention deficit hyperactivity disorder (ADHD), although this association is poorly documented.Herein, we report a case of a female child carrying the novel heterozygous missense variant c.5996c>T (p.Pro1999Leu) at exon 42 (NM_000068.4) of CACNA1A, who presented with intractable seizures complicated with ADHD and was treated with acetazolamide.This article describes the patient's favorable response to acetazolamide, which alleviated the symptoms of her CACNA1A channelopathy.A 10-year-old girl born of a non-consanguineous marriage presented with a history of right-sided focal motor clonic seizures involving her right-sided extremities since the age of 6.She was the second-born child, with an unremarkable birth and family history.Her developmental milestones were achieved normally.There was no family history of epilepsy.The first seizure episode occurred while the child was asleep and lasted approximately 30 seconds, manifesting as rhythmic jerking of her right extremities.Her