CDKL5 Deficiency Disorder – Symptoms, Causes, & Treatment

CDKL5 Deficiency

A rare X-linked genetic condition known as CDKL5 deficiency disorder was discovered in 2004. When a disease is X-linked, it indicates that the X chromosome contains the gene causing the issue. The gene known as “cyclin-dependent kinase-like 5” is found on the X chromosome. A kid receives two X chromosomes from the mother and one X and one Y chromosome from the father.

The CDKL5 gene instructs the body to produce a protein necessary for healthy brain development. The majority of individuals with CDD experience seizures in their first few months of life. The baby subsequently experiences developmental issues that result in a significant developmental delay.

Symptoms of CDKL5 Deficiency Disorder

Seizures that start in infancy are an indicator of this illness. They can start anywhere in the first three months of life, although they can start as soon as one week after birth. These seizures vary with age and have a consistent pattern. Seizures are resistant to medication and might happen as frequently as once a day.

The other significant indications of this illness include severe developmental delays. Individuals with intellectual limitations frequently cannot talk. Just one-third of people with CDKL5 deficiency condition are able to walk independently. Also, there is a delay in gross motor abilities including standing, sitting, and walking. There is also an impact on fine motor abilities. Other symptoms of this condition include:

  • Repetitive hand motions, such as licking or clapping
  • Teeth clenching
  • Sleep disturbance
  • Having trouble eating
  • Issues with the stomach (constipation, reflux of the stomach)
  • Abnormal breathing patterns

Along with these characteristic traits, people with this illness also have wide-spaced teeth and a high roof of the mouth. Also, they have a pronounced space between the top lip and nose, big, deep-set eyes, and a high forehead. Scoliosis, tapering fingers, and a tiny skull are further potential characteristics.


An essential protein for proper brain development and function is encoded by the CDKL5 gene. Medical experts think that there is an involvement of this protein in the migration, development, and creation of nerve cells in the brain. Even if they are unsure of exactly what this protein does or how it produces particular symptoms. Brain development suffers when the CDKL5 protein is lacking.

There is an X-linked dominant pattern of inheritance for this gene. This pattern means that the condition can exist with only one X chromosome carrying the mutant gene. Usually, mutations occur early in the development of the embryo or during the egg cell division processes. This implies that individuals without a family history of CDKL5 deficient disease may nonetheless develop the ailment.

Treatment for CDKL5 Deficiency Disorder

The only treatments available for this illness are supportive and symptomatic. There is no known cure. Speech, occupational, physical, and augmentative communication therapies are all crucial and need to begin early in childhood.

Given that many individuals with this illness struggle with oral feeding, a nutritionist can assist in designing a diet that provides all the nutrients required. In the case of scoliosis, braces could be necessary. The most challenging symptom to manage is seizures as they are drug-resistant. Certain individuals have had success through vagal nerve stimulation or dietary adjustments.

The Bottom Line

A person with CDKL5 benefits from an early diagnosis. Because it allows them to begin treatment with a multidisciplinary team. They act to support their treatments and take care of any health issues that may arise. There is a lack of information on the history of CDKL5 deficient illness.