Symptoms of CDKL5 disorder

What are the symptoms of CDKL5 disorder?

While every child with CDKL5 disorder is different in terms of physical symptoms and developmental milestones met, the condition includes a number of common identifiable features:

  • Early-onset epilepsy
    • 90 percent of children with CDKL5 disorder will develop seizures before 3 months of age.
    • This commonly includes epileptic spasms, though they may not be the first seizure type.
    • Seizures with multiple distinct phases are common (such as the hypermotor-tonic-spasms sequence).
  • Impaired gross motor skills (such as walking)
  • Impaired fine motor skills (such as grasping)
  • Global developmental delays and intellectual disability
  • Impaired language/communication and social skills
  • Autistic features (though many children don’t meet formal criteria for autism spectrum disorder)
  • Low muscle tone
  • Poor eye contact and visual fixation; often with cortical visual impairment (difficulty interpreting vision in the brain, but the eyes are structurally normal)
  • Sleep abnormalities
  • Swallowing and feeding difficulties
  • Growth restriction
  • Gastrointestinal reflux and/or constipation
  • Scoliosis, hip dysplasia or other orthopedic complications from low muscle tone
  • Development of high muscle tone in the legs over time

Less common features of CDKL5 disorder

  • Microcephaly (small head size)
  • Subtle characteristic facial features including broad or prominent forehead, large deep-set eyes, and/or full lips.
  • Stereotypic movements or movement disorders
  • Features overlapping with Rett syndrome and other neurodevelopmental disorders, including cold hands and feet, unexplained laughing or screaming spells, irregular breathing (periods of fast or slow breathing) and teeth grinding.