Specimen Requirements

Plasma or serum and urine are required for this test. Plasma or serum specimen should be obtained sometime during the 24-hour urine collection or within 48 hours of the 24-hour urine collection.

Preferred:

Plasma

Container/Tube:  Light green-top (lithium heparin gel) tube(s)

Specimen:  1 mL (minimum volume:  0.5 mL) of lithium heparin plasma

Transport Temperature:  Ambient

Collection Instructions:  Spin down immediately and send entire tube to laboratory. If there is a delay in transport of >8 hours, send specimen refrigerated.

Note:  1. Patient’s height and weight are required on request form for calculation of the creatinine clearance.

2. Indicate plasma on request form.
3. Label specimen appropriately (plasma).

Alternate:

Serum

Container/Tube:  Gold-top serum gel tube(s) - Plain, red-top tube is also acceptable.

Specimen:  1 mL (minimum volume:  0.5 mL) of serum

Transport Temperature:  Ambient

Collection Instructions:  Allow specimen to clot for approximately 10 minutes and spin down. If drawing gold-top serum gel tube, send entire tube to laboratory. If drawing plain, red-top tube, remove serum and place in separate plastic vial. If there is a delay in transport of >8 hours, send specimen refrigerated.

Note:  1. Patient’s height and weight are required on request form for calculation of the creatinine clearance.

2. Indicate serum on request form.
3. Label specimen appropriately (serum).

Urine

Send entire 24-hour urine collection in a plastic urine container. No preservative. Refrigerate specimen during collection, and send specimen refrigerated.

Note:  1. Patient’s height and weight and starting and ending times of collection are required on request form for processing.
2. Follow instructions in “Urine Collection” in “Special Instructions.”