Phosphorus
Label Mnemonic: PO4
Epic code: LAB113
Order form: Laboratory Requisition
Supply order: Supply Order Form
Billing: Billing Policies
CPT code: 84100
Specimen(s):
Plasma
Collection Medium:
Plasma Separator Tube 4.5 mL
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
3 mL whole blood from light green top tube or ONE Microtainer® for pediatric patients.
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
1 hour (upon receipt in laboratory)
Reference Range:
Reference ranges based on package insert (Roche Diagnostics PHOS2 
ver. 2)

   Age          Male (mg/dL)	Female (mg/dL)
0-30 days         3.9-6.9          4.3-7.7
1-12 months       3.5-6.6          3.7-6.5
1-3 years         3.1-6.0          3.4-6.0
4-6               3.3-5.6          3.2-5.5
7-9               3.0-5.4          3.1-5.5
10-12             3.2-5.7          3.3-5.3
13-15             2.9-5.1          2.8-4.8
16-18             2.7-4.9          2.5-4.8
>18               2.5-4.5          2.5-4.5

Reference ranges updated 10/13/2015.
Comments:
Refer to BD Microtainer® Tubes product sheet for detailed sample collection instructions.

This test is also performed in the Iowa River Landing (IRL) clinical laboratory (for specimens drawn at that site).
Test Limitations:
Criterion: Recovery within plus or minus 10% of initial value.

Plasma
Icterus: No significant interference up to an I index of 60.

Hemolysis: Significant positive interference at an H index greater 
than 
300 (approximate hemoglobin concentration: 300 mg/dL). NOTE: This 
interference results from inorganic phosphates produced by the action 
of phosphatases on organic phosphates, both of which are released from 
the red cell upon hemolysis (2).

Lipemia (Intralipid): No significant interference up to an L index of 
800.  There is poor correlation between turbidity and triglycerides 
concentration.

Drugs:  No interference was found at therapeutic concentrations using 
common drug panels.
Methodology:
Molybdate UV
Sample Processing:
Centrifuge at a speed and time necessary to get barrier separation of plasma/serum and cells within 1 hour of collection. Send specimen in original tube. Do Not transfer to another tube.
Each sample must be labeled with at least TWO full patient identifiers (First/Last Name & DOB are sufficient for non-UIHC affiliated clients) to avoid sample rejection/delays.
Sample Storage:
Refrigerate.
All sample storage requirements are intended for delivery to UIHC within 24 hours of collection for testing. If samples won't arrive in this time period, please call the UIHC Core Lab for alternative storage/shipping instructions (319-356-3527).
Transport Instructions:
Place labeled specimen into zip-lock type biohazard bag; seal bag.
Place completed requisition into outside pocket of bag.
Transport in cooler with refrigerated coolant packs.
CPT Code:
84100