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Test Name:Phosphorus  
Epic Order Code:LAB113  
CPT Code:84100  
Specimen(s) Type:Plasma or Serum  
Acceptable Container(s):Top is light green and gold.
Testing Schedule:24 hrs/day, 7 days/week
Turn Around Time:STAT: 1 hour  
 Routine: 2 hours  
Collection Information:No special patient preparation is required. Obtain specimen by standard collection procedures.
Transport Information:Deliver to lab immediately. All specimens must be signed into the laboratory.
Reference Clients:If unable to deliver to the lab within 1 hour, centrifuge the specimen and remove plasma/serum from the red cells. Store and transport at 2-8° C. Specimen must be received in the lab within 24 hours.
Causes for Rejection:Improperly labeled, incorrect container, contaminated, insufficient quantity, incorrect/delay in transport.
Reference Range:2.7 - 4.5 mg/dL
 Critical: < 1.0 or > 9.0 mg/dL
Additional Information:Test included in Renal Panel
 Significant positive interference is caused from inorganic phosphates produced by the action of phosphatases on organic phosphates, both of which are released from the red cells upon hemolysis. This can yield falsely elevated results.
 Phospholipids contained in liposomal drug formulations (i.e.,AmBisome) may be hydrolyzed in the test due to the acidic reaction pH and thus lead to elevated phosphate results.