11-Deoxycorticosterone, Serum
Use
This test is useful for diagnosing suspected 11-hydroxylase deficiency, aiding in the differential diagnosis between 11-beta-hydroxylase 1 (CYP11B1) and 11-beta-hydroxylase 2 (CYP11B2) deficiencies. It is also instrumental in diagnosing glucocorticoid-responsive hyperaldosteronism and in evaluating children with congenital adrenal hyperplasia who have a positive newborn screen for 17-hydroxyprogesterone, where the elevation suggests a possible 11-hydroxylase deficiency.
Special Instructions
A morning (8 a.m.) specimen is preferred for accurate results. Ensure serum is centrifuged and aliquoted into a plastic vial promptly. Follow handling and storage instructions closely to maintain specimen integrity. Be cautious of the specimen's stability and rejection conditions, especially avoiding gross hemolysis.
Limitations
Elevated levels found in newborns and preterm infants can affect the accuracy of diagnosis due to physiologically high adrenal steroid levels at birth. Mineralocorticoid levels in infants younger than 7 days are often elevated, and interpretation requires caution. ACTH1-24 testing carries risks of allergic reactions and should be conducted under supervision. Diagnosis of congenital adrenal hyperplasia, particularly rare variants, may need expert interpretation due to a lack of normative data.
New York Approved
Methodology
Mass Spectrometry (LC-MS/MS)
Biomarkers
LOINC Codes
- 1656-8
- 1656-8
Result Turnaround Time
3-10 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.4 mL
Container
Plastic vial
Collection Instructions
1. Morning (8 a.m.) specimen is preferred. 2. Centrifuge and aliquot serum into a plastic vial.
Storage Instructions
Refrigerated specimens are preferred for up to 21 days, ambient for 7 days, and frozen for 21 days.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 21 days |
| Frozen | 21 days |