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Inorganic Phosphate, PO4

Testing Information

Sample Type
Test Codes
CPT Code
Testing Area
Core Lab - Chemistry
Test Methodology
Abbott Alinity - Spectrophotometry
Reference Range
0-6 months: 4.2-7.8 mg/dL7-12 months: 4.0-6.8 mg/dL2 years-19 years: 3.4-5.3 mg/dL>19 years: 2.5-4.4 mg/dLCritical Value: <1.0 mg/dL
Expected Turnaround Time
Results Available 24 hours from Receipt
Specimen Collection Criteria
Collect one gold top SST tube (minimum whole blood: 1 mL). Let specimen clot for 30-60 minutes and then centrifuge to separate serum from cells. Refrigerate after centrifugation.
Rejection Criteria
Grossly hemolyzed specimens, quantity not sufficient, improperly labeled
Specimen Validity and Retention
Centrifuged SST Tubes:Room Temperature (20-25°C): 2-4 hoursRefrigerated (2-8°C): 7 daysFrozen (-20°C or greater): UnacceptableSerum Aliquots:Room Temperature (20-25°C): 2-4 hoursRefrigerated (2-8°C): 7 daysFrozen (-20°C or greater): 7 daysSpecimens retained for 7 days after testing
Courier Transportation
Transport centrifuged tube refrigerated (2-8°C)
Clinical Utility
Phosphorus is used in the diagnosis of a wide array of disorders including dehyrdation, malnourishment, hyperparathyroidism, and vitamin D deficiency, among others.