title: CDKL5 gene-related epileptic encephalopathy: electroclinical findings in the first year of life.
abstract: OBJECTIVE
  Cyclin-dependent kinase-like 5 (CDKL5) gene abnormalities cause an early-onset epileptic encephalopathy. We performed video-electroencephalography (video-EEG) monitoring early in the course of CDKL5-related epileptic encephalopathy in order to examine the early electroclinical characteristics of the condition.
  
  
  METHODS
  We used video-EEG to monitor six infants (five females, one male) with CDKL5-related epileptic encephalopathy (five mutations; one deletion), at ages 45 days to 12 months and followed them up to the ages of 14 months to 5 years (mean age 23 mo). We focused our analysis on the first year of life. The results were evaluated against those of a comparison group of nine infants (aged below 1y) with epileptic encephalography who had tested negative for CDKL5 mutations and deletions.
  
  
  RESULTS
  One infant exhibited normal background activity, three exhibited moderate slowing, and two exhibited a suppression burst pattern. Two participants had epileptic spasms and four had a stereotyped complex seizure pattern, which we defined as a 'prolonged' generalized tonic-clonic event consisting of a tonic-tonic/vibratory contraction, followed by a clonic phase with series of spasms, gradually translating into repetitive distal myoclonic jerks. Seizure duration ranged from 2 to 4 minutes. The EEG correlate of each clinical phase included an initial electrodecremental event (tonic vibratory phase), irregular series of sharp waves and spike slow waves (clonic phase with series of spasms), and bilateral rhythmic sharp waves (time locked with myoclonus).
  
  
  CONCLUSIONS
  Infants with CDKL5-related early epileptic encephalopathy can present in the first year of life with an unusual electroclinical pattern of 'prolonged' generalized tonic-clonic seizures.
authors.affiliation: Paediatric Neurology Unit and Laboratories, A. Meyer Children's Hospital, University of Florence, Florence, Italy. r.guerrini@meyer.it
authors.forename: Federico
authors.initials: F
authors.lastname: Melani
authors.forename: Davide
authors.initials: D
authors.lastname: Mei
authors.forename: Tiziana
authors.initials: T
authors.lastname: Pisano
authors.forename: Salvatore
authors.initials: S
authors.lastname: Savasta
authors.forename: Emilio
authors.initials: E
authors.lastname: Franzoni
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Ferrari
authors.forename: Carla
authors.initials: C
authors.lastname: Marini
authors.forename: Renzo
authors.initials: R
authors.lastname: Guerrini
mesh_terms: D058256:Brain Waves / Q000235:genetics*; D002675:Child, Preschool; D002658:Developmental Disabilities / Q000175:diagnosis / Q000235:genetics; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000235:genetics / Q000503:physiopathology; D065768:Lennox Gastaut Syndrome; D008297:Male; D009154:Mutation / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D013036:Spasms, Infantile / Q000235:genetics / Q000503:physiopathology
chemical_list: D017346:Protein Serine-Threonine Kinases; C114482:CDKL5 protein, human