Laboratory Medicine

Test catalogue

Intact Fibroblast Growth Factor 23 (FGF23)
Test Name Intact Fibroblast Growth Factor 23 (FGF23)
Specimen Type / Requirements Container Type = 1 Lavender (EDTA) Minimum Testing Volume = 2mL plasma Tubes must fill to at least ½ or greater of its vacuum capacity Measurement of FGF23 can assist in diagnosis and management of disorders of phosphate and bone metabolism in patients with either normal or impaired renal function. Increased FGF23 concentrations are present in individuals with renal phosphate-wasting diseases such as autosomal dominant hypophosphatemic rickets (ADHR), autosomal recessive hypophosphatemic rickets (ARHR), X-linked hypophosphatemia rickets (XLH) and tumor induced osteomalacia (TIO).
Specimen Handling Collection Instructions: Biochemist approval required prior to ordering or collecting specimen for this test. Call ext 2226 or 2172 to seek approval. Collect specimen in EDTA lavender vacutainer tube. Write your initials, date and time of collection on the collection label. Laboratory Staff Instructions: Separate EDTA plasma from the clot and red cells by centrifugation as soon as possible. Freeze the aliquot at -20C. Send frozen. Rejection Criteria: Thawed samples. Serum and heparinized plasma samples are unacceptable. Transportation: Transport on ice to core lab as soon as possible.
Required Documentation
Turnaround Time (TAT) 30days	Test Utilization
Reference Value < 96 pg/mL Note: FGF23 concentrations must be interpreted in conjunction with plasma phosphate measurements and urinary fractional excretion of phosphate. Do not interpret FGF23 concentrations as absolute evidence of the presence or the absence of tumor induced osteomalacia (TIO). Patients receiving burosumab should not be monitored using the IFGF23 assay.
Test Code MISCS	Methodology Chemiluminescent Immunoassay
Testing Location ROUHNT06	Other Information Last Update: Aug 24, 2022

Intact Fibroblast Growth Factor 23 (FGF23)

Test Name

Intact Fibroblast Growth Factor 23 (FGF23)

Specimen Type / Requirements

Container Type = 1 Lavender (EDTA)

Minimum Testing Volume = 2mL plasma

Tubes must fill to at least ½ or greater of its vacuum capacity

Measurement of FGF23 can assist in diagnosis and management of disorders of phosphate and bone metabolism in patients with either normal or impaired renal function. Increased FGF23 concentrations are present in individuals with renal phosphate-wasting diseases such as autosomal dominant hypophosphatemic rickets (ADHR), autosomal recessive hypophosphatemic rickets (ARHR), X-linked hypophosphatemia rickets (XLH) and tumor induced osteomalacia (TIO).

Specimen Handling

Collection Instructions: Biochemist approval required prior to ordering or collecting specimen for this test. Call ext 2226 or 2172 to seek approval. Collect specimen in EDTA lavender vacutainer tube. Write your initials, date and time of collection on the collection label.

Laboratory Staff Instructions: Separate EDTA plasma from the clot and red cells by centrifugation as soon as possible. Freeze the aliquot at -20C. Send frozen.

Rejection Criteria: Thawed samples. Serum and heparinized plasma samples are unacceptable.

Transportation:

Transport on ice to core lab as soon as possible.

Required Documentation

Turnaround Time (TAT)

30days

Test Utilization

Reference Value

< 96 pg/mL

Note: FGF23 concentrations must be interpreted in conjunction with plasma phosphate measurements and urinary fractional excretion of phosphate. Do not interpret FGF23 concentrations as absolute evidence of the presence or the absence of tumor induced osteomalacia (TIO). Patients receiving burosumab should not be monitored using the IFGF23 assay.

Test Code

MISCS

Methodology

Chemiluminescent Immunoassay

Testing Location

ROUHNT06

Other Information

Last Update: Aug 24, 2022