Test Code Billings Clinic: 4792 Mayo: 21OH 21-Hydroxylase Antibodies, Serum
Reporting Name
21-Hydroxylase Ab, SPerforming Laboratory
Mayo Clinic Laboratories in RochesterUseful For
Investigating adrenal insufficiency
Aiding in the detection of those at risk of developing autoimmune adrenal failure in the future
Method Name
Enzyme-Linked Immunosorbent Assay (ELISA)
Ordering Guidance
Testing for autoantibodies against 21-hydroxylase is recommended following confirmation of adrenal insufficiency to help differentiate between causes of primary adrenal insufficiency
Shipping Instructions
Ship specimen frozen on dry ice
Specimen Required
Collection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial to remove from cells or gel prior to shipping.
Specimen Type
SerumSpecimen Minimum Volume
0.2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Frozen | 14 days |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Reference Values
Negative
Interpretation
This is a qualitative test. A positive result indicates the presence of autoantibodies to 21-hydroxylase and is consistent with Addison disease.
Utilizing an index value of <45 as a negative cutoff, this assay has a clinical sensitivity and specificity of 87.0% (95% CI: 79.4%-92.2%) and 99.3% (95% CI: 97.5%-99.8%), respectively.
Day(s) Performed
Wednesday
Report Available
3 to 9 daysTest Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
83516
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
21OH | 21-Hydroxylase Ab, S | 85363-0 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
607788 | 21-Hydroxylase Ab, S | 85363-0 |