Cytochrome b5 Reductase Enzyme Activity, Blood

Test Code

39856

CPT Codes
82657

Preferred Specimen

6 mL whole blood collected in an ACD solution B (yellow-top) tube

Minimum Volume

1 mL

Other Acceptable Specimens

Whole blood collected in: EDTA (lavender-top) tube

Instructions

Send specimen in original tube. Do not transfer blood to other containers. Patient's age is required.

Transport Container

ACD solution B (yellow-top) tube

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: Unacceptable
Refrigerated: 18 days
Frozen: Unacceptable

Methodology
Kinetic Spectrophotometry

FDA Status
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

Setup Schedule

Weekly

Reference Range

≥12 months

7.8-13.1 U/g Hb

Reference values have not been established for patients who are <12 months of age.

Clinical Significance

Evaluation of patients with cyanosis.
Confirming cases of suspected cytochrome b5 reductase (methemoglobin reductase) deficiency.
Functional studies in families with cytochrome b5 reductase deficiency.

Performing Laboratory

Mayo Clinical Laboratories

200 1st Street SW

Rochester, MN 55905-0001

Last Updated: November 6, 2024

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.