Fibroblast Growth Factor 23 (FGF23) Level, Plasma

Sunquest Code:FGFT23  
Epic Code:LAB6784Epic Name:Fibroblast Growth Factor 23
Methodology:Immunometric Enzyme Assay
Turnaround Time:Specimens are sent to reference laboratory Mon-Fri; results are reported within 1-3 days.

This test uses a reagent or kit labeled by the manufacturer as Research Use Only. Its performance characteristics were 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.

Collection Instructions

Optimal Volume:3 mL
Minimum\Peds Volume:1.2 mL
Container:Purple (EDTA)
Causes for Rejection:Gross hemolysis

Processing and Shipping

Specimen Processing:Centrifuge and aliquot 1.5 mL, 0.5 mL minimum.
Shipping Instructions:Ship at frozen temperatures (preferred).
Stability:Stability: Refrigerated - 14 days; frozen - 90 days
Test Performed at or Referral Lab Lab Sendouts  (Mayo)
Referral Lab number:FGF23


Reference Range:


Normal infants less than 3 months of age

Results may be significantly elevated (i.e., >900 RU/mL)

3 mo - 17 y

≤ 230 RU/mL


≤ 180 RU/mL



Use:Diagnosing and monitoring oncogenic osteomalacia; diagnosing x-linked hypophosphatemia or autosomal dominant hypophosphatemic rickets; predicting treatment response to calcitriol or vitamin D analogs in patients with renal failure.

Click HERE to Report test errors or omissions.
*If no email program is associated with this computer, please contact: for TestID: 6376"