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Start free with EleplanCDKL5-deficiency disorder
ORPHA:505652Disease
Also called CDD
What it is
A rare genetic neurodevelopmental disorder characterized by early-onset drug-resistant seizures and severe neurodevelopmental impairment with major motor development delay.
Key facts
- Prevalence
- 1-9 / 100 000 (at birth, Europe)
- Age of onset
- Infancy, Neonatal
- Inheritance
- X-linked dominant
- Classified as
- Disease
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Signs and symptoms
Common30–79%
36- Abnormal muscle tone
- Autistic behavior
- Bilateral tonic-clonic seizure
- Broad forehead
- Broad proximal phalanges of the hand
- Bruxism
- Cerebral visual impairment
- Coldness
- Constipation
- Deeply set eye
- Deep philtrum
- Delayed gross motor development
- Delayed speech and language development
- Everted lower lip vermilion
- Feeding difficulties
- Focal-onset seizure
- Gait disturbance
- Gastroesophageal reflux
- Gastrostomy tube feeding in infancy
- Growth delay
- Hypotonia
- Hypsarrhythmia
- Impaired pain sensation
- Infantile spasms
- Intellectual disability
- Moderate global developmental delay
- Multifocal epileptiform discharges
- Myoclonic seizure
- Poor head control
- Prominent forehead
- Reduced eye contact
- Severe global developmental delay
- Sleep-wake cycle disturbance
- Stereotypical hand wringing
- Tactile hypersensitivity
- Thick vermilion border
Sometimes5–29%
15and 7 more in this range
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Benefit programs to look at
Programs whose eligibility touches the same ICD-10 categories. Eligibility is decided by the administering agency, never by this page.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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