- 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 of chronic granulomatous disease (CGD):
A primary immunodeficiency disorder characterized by recurrent, severe bacterial and fungal infections of the skin, lymph nodes, liver, lungs, bones, or visceral organs. Dysregulated inflammatory responses result in granulomas.
Incidence: Approximately 1 in 250,000 births.
Inheritance: X-linked recessive for CYBB; de novo mutations in 10-20 percent of affected males.
Cause: Pathogenic mutations in the CYBB gene result in X-linked CGD. Autosomal recessive CGD may result from mutations in NCF1 (25 percent), CYBA (<5 percent), NCF2 (<5 percent) and NCF4 (very rare).
Clinical Sensitivity: 68 percent for CGD.
Methodology: PCR followed by high-resolution melting analysis of the entire coding region and intron/exon boundaries of the CYBB gene. Identified sequence variants are confirmed using targeted, bidirectional sequencing.
Analytical Sensitivity and Specificity: 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Deep intronic mutations in CYBB are not detected in males or females. Large CYBB gene deletions/duplications will not be detected in carrier females. Breakpoints of large deletions/duplications will not be determined in males. Mutations in genes other than CYBB are not evaluated.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.
See Compliance Statement C: www.aruplab.com/CS
|Component Test Code*||Component Chart Name|
|2006363||CYBB for Chronic Granulomatous Disease|