Amelioration of intractable epilepsy by adjunct vagus nerve stimulation therapy in a girl with a CDKL5 mutation.

We report the case of on an 8-year-old girl with a cyclin-dependent kinase-like 5 mutation and who underwent vagus nerve stimulation (VNS) therapy for 2years. She had developed epilepsy at the age of 6months and had severe developmental delays. Initially, she had tonic and tonic-clonic seizures; however, around the age of 5years, she also developed epileptic spasms. These seizures were never completely controlled by conventional medical treatments. At the age of 7, after VNS initiation, her seizure frequency markedly reduced, and abnormal electrical activities on her electroencephalography tests strikingly decreased. Moreover, using questionnaires, we confirmed an improvement in her quality of life in the fields of alertness and activity. Although the efficacy of VNS therapy for patients with intractable epilepsy associated with a genetic anomaly has not been fully established, adjunctive VNS therapy may widen the scope of treatment choices available to these patients.