Seizures: Most people with pathogenic variants experience seizures. They typically begin in the first days or months of life and can be very difficult to control. Parents may be the first to notice a twitch in their child’s eyelid, a subtle movement of a single hand or foot which may then spread to involve the other side of the body. These seizures are resistant to most anti-seizure medications. In other patients, the seizures occur mostly at night and may result in unexplained awakenings, including shouting, or unusual movements during sleep.
Developmental Delay: Persons with KCNT1-related epilepsy may begin developing normally until the onset of seizures, then experience delays in developmental milestones, including motor, speech, and cognitive delays. Some may experience stagnated development or loss of skills.
Early-onset: These syndromes include Early Infantile Epileptic Encephalopathy (EIEE) and Malignant migrating focal seizures of infancy (MMPSI) now called Epilepsy of Infancy with Migrating Focal Seizures (EIMFS).
Later onset: Autosomal Dominant Nocturnal Frontal Lobe Epilepsy (ADNFLE), now called Autosomal-dominant Sleep Hypermotor Epilepsy (ADSHE)
A diagnosis of KCNT1 is confirmed through genetic testing that identifies a mutation in the KCNT1 gene. KCNT1 gene variants can result in different phenotypes. These variants are most often categorized as pathogenic or likely pathogenic. While many variants that cause disease occur randomly (de novo), other KCNT1 variants are inherited in an autosomal dominant fashion, often by a parent with no symptoms.
There are no treatments specifically for KCNT1-related disorders today, but many patients benefit from a ketogenic diet. Treatment goals vary by child but include minimizing seizures, treating symptoms, and providing opportunities to support development and prevent the loss of skills. Children with early onset seizures benefit from a multidisciplinary care team including physical, speech, and vision therapies. Those with later-onset KCNT1 and nocturnal seizures may also have autism spectrum disorder, autistic-like characteristics and/or behavioral issues, so early intervention is important. There are several companies investigating treatments for KCNT1-related disorders, so better treatments or a cure may be found soon.
The average person with a rare disease sees 7.3 specialists over a span of 5-7 years before receiving an accurate diagnosis. AmbitCare Ambassadors provide free services including listening to understand your challenges, guiding you on potential next steps, and recommending resources.