Test Overview

Test Methodology

Kinetic Spectrophotometry (KS)

Test Usage

Confirming cases of heterozygous or homozygous methemoglobin reductase deficiency; genetic studies in families with methemoglobin reductase deficiency.

Reference Range*

6.6 - 13.3 U/g hemoglobin

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details

Days Test Performed

Tuesday, Thursday

Analytic Time

2 - 10 days

Soft Order Code




Cytochrome B5 Reductase
Methemoglobin Reductase, Erythrocytes

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Laboratory Reference

Mayo METR (9322)

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Specimen Requirements

Offsite Collection Instructions

Collect blood in an yellow top (ACD) solution B tube. Refrigerate intact specimen; do not freeze.

Normal Volume

6 mL ACD (solution B) whole blood

Minimum Volume

1 mL ACD (solution B) whole blood

Additional Information

Test sent to Mayo Medical Laboratories.

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Fee Codes

CPT Code


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