Abstracts

Rationale: To clarify characteristics of seizures in infants with CDKL5 mutation/deletion for early diagnosis. Methods: We investigated ictal video-EEG in 4 infants with CDKL-5 (cyclin-dependent kinase-like 5) mutation/deletion; 1 boy with single base missense mutation, 2 girls with single base deletion with frameshift, 1 girl with microdeletion. We performed and analyzed video-EEG monitoring between 3-30 months of age. Results: Epilepsy started between 2-7 weeks of age in all. Common characteristics of recorded seizures stared with bawling, followed by gestural automatism or head/eye deviation, then tonic posturing for 10 seconds accompanied with marked slowing or attenuation on EEG, thereafter mild rhythmic (2Hz) jerking of extremities, finally evolved to epileptic spasms in a series of short intervals (3-4 sec). Interictal EEG showed no abnormal findings at the onset of epilepsy, but hypsarrhythmia or diffuse spike and waves between 6-18 months. Conclusions: Infants with CDKL5 mutation/deletion are reported to have epileptic spasms in a series, generalized tonic clonic seizures, or migrating focal clonic seizures. The present study revealed that epilepsy with CDKL5 mutation/deletion started with peculiar combined seizures instead of just simple epileptic spasms or GTC in infancy. Normal interictal EEG at the onset of epilepsy and ictal EEG findings with marked slowing or attenuation also would be useful diagnostic clues to CDKL5 mutation/deletion.