Test Overview

Test Methodology

Radioimmunoassay (RIA)

Reference Range*

0 - 2830 ng/mL

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

Test Details

Days Test Performed

1st and 3rd Thursday of the month

Analytic Time

21-44 days

Soft Order Code


MiChart Code

C4ades Arg Level (Sendout)

Test Updated

Update Type: CPT Code Change

Updated Date: 04/15/2020



C4ades Arg Level

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Laboratory Reference

Mayo FC4A (57800) (National Jewish Health C4AL)

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Specimen Requirements

Special Handing

Must arrive in lab or aliquot and freeze within 30 minutes.


Lavender Top Tube

Normal Volume

1 mL EDTA plasma

Minimum Volume

0.5 mL EDTA plasma

Additional Information

Test sent to Mayo Medical Laboratories; performed by National Jewish Health.

Billing Information

Fee Codes

CPT Code


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