This is a second tier test and REQUIRES PERMISSION from ARUP's Genetic Counselor (800-242-2787, x2141) before ordering. Preferred initial test is the sequencing and deletion/duplication test.
- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics: Vary widely but may include early onset intractable seizures, severe developmental delay, with females often exhibiting features of Rett syndrome.
Incidence: Unknown; more frequent in females than males.
Inheritance: X-linked dominant; reported cases are de novo.
Penetrance: 100 percent.
Cause: Pathogenic CDKL5 gene mutations.
Clinical Sensitivity: Unknown.
Methodology: Multiplex ligation-dependent probe amplification (MLPA) to detect large CDKL5 coding regiondeletions/duplications.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Single base pair substitutions, small deletions/duplications, regulatory region mutations, and deep intronic mutations will not be detected. The breakpoints of large deletions/duplications will not be determined.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|2004928||CDKL5-Related Disorders Del/Dup Specimen|
|2004929||CDKL5-Related Disorders Del/Dup Interp|
- Atypical Rett (CDKL5)
- Epileptic Encehpalopathy, Early Infantile 2
- Infantile Spasms/Atypical Rett
- Rett-Like Syndrome