The Ketogenic Diet: An Underrecognized Therapy for Rett Syndrome.

Rett syndrome is an X-linked dominant neurodevelopmental disorder characterized by cognitive and communicative regression, stereotypies and loss of hand use. Epilepsy is present in 50% to 90% with approximately one-third having refractory epilepsy. The ketogenic diet has been used as an antiseizure therapy for more than a century; however, there is limited data on its use in Rett syndrome. In this retrospective single-center case series, we present 9 children with Rett syndrome who were placed on ketogenic diet. There was ≥50% improvement in seizure frequency in 67% (6/9) and 44% (4/9) at 6 and 12 months, respectively. Patients with ≥50% seizure reduction had an improvement in cognition and alertness. All 9 had a gastrostomy tube, with 8 starting ketogenic diet with a ketogenic formula and 1 with a food-based diet. The ketogenic diet is well tolerated and has high efficacy for seizures associated with Rett syndrome with two-thirds reporting significant seizure reduction. The presence of a gastrostomy tube can help the initiation and titration of ketogenic diet.