Creatinine
Test Summary
Creatinine is the endproduct of creatine metabolism. Creatine is present primarily in muscle and the amount of creatinine produced is related to total skeletal muscle mass. Daily creatinine production is fairly constant except when there is massive injury to muscle. The kidneys excrete creatinine very efficiently and blood levels and daily urinary excretion of creatinine fluctuates very little in healthy normal people. Since blood and daily urine excretion of creatinine shows minimal fluctuation, creatinine excretion is useful in determining whether 24-hour urine specimens for other analytes (e.g., protein) have been completely and accurately collected.
Aliases
- Creat
Specimen Collection
Special Instructions
N/A
Preferred Specimen
1 mL serum
Minimum Volume
1 mL
Instructions
Barrier tubes (serum separator tubes or plasma separator tubes) are preferred. If non-barrier tubes are utilized, the serum/plasma must be removed immediately after centrifuging and placed in a screw-cap transfer tube.
Collection notes: Avoid hemolysis. Invert tubes at least 8 times. Allow to clot in an upright position for 30 minutes. Within 2 hours, centrifuge tubes 10 minutes. Keep tightly stoppered.
Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.
Collection notes: Avoid hemolysis. Invert tubes at least 8 times. Allow to clot in an upright position for 30 minutes. Within 2 hours, centrifuge tubes 10 minutes. Keep tightly stoppered.
Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.
Patient Preparation
N/A
Storage
Original tube preferred, may be sent in a screw-top transfer tube.
Transport Temperature
Room Temperature or Refrigerated
Specimen Stability
- Room Temperature = 7 days
- Refrigerated = 7 days
- Frozen = 3 months
Limitations
N/A
Other Acceptable Specimens
Plasma from Lithium Heparin (Light Green Top) tube
Unacceptable Specimens
Hemolysis, Lipemia, incorrect specimen type, insufficient sample volume, improper storage conditions, exceeds specimen stability guidelines, contaminated sample.
Order Code
CRET
EPIC (Premier) Code
LAB127
Includes
N/A
CPT Code
- 82565
Billing Code
- 300209
CPT Statement
Methodology
Spectrophotometry (SP)
FDA Status
FDA Approved
Physician Attestation of Informed Consent
N/A
Testing Laboratory
CompuNet Clinical Laboratories, LLC
2308 Sandridge Drive
Moraine OH, 45439
2308 Sandridge Drive
Moraine OH, 45439
Department
Chemistry
Reference Range
See Report
Setup Schedule / Expected Turnaround Time
24/7; Report available: Daily
Specimen Collection
Special Instructions
N/A
Preferred Specimen
1 mL serum
Minimum Volume
1 mL
Instructions
Barrier tubes (serum separator tubes or plasma separator tubes) are preferred. If non-barrier tubes are utilized, the serum/plasma must be removed immediately after centrifuging and placed in a screw-cap transfer tube.
Collection notes: Avoid hemolysis. Invert tubes at least 8 times. Allow to clot in an upright position for 30 minutes. Within 2 hours, centrifuge tubes 10 minutes. Keep tightly stoppered.
Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.
Collection notes: Avoid hemolysis. Invert tubes at least 8 times. Allow to clot in an upright position for 30 minutes. Within 2 hours, centrifuge tubes 10 minutes. Keep tightly stoppered.
Do NOT re-centrifuge tubes. Do NOT freeze the primary collection tube.
Patient Preparation
N/A
Storage
Original tube preferred, may be sent in a screw-top transfer tube.
Transport Temperature
Room Temperature or Refrigerated
Specimen Stability
- Room Temperature = 7 days
- Refrigerated = 7 days
- Frozen = 3 months
Limitations
N/A
Other Acceptable Specimens
Plasma from Lithium Heparin (Light Green Top) tube
Unacceptable Specimens
Hemolysis, Lipemia, incorrect specimen type, insufficient sample volume, improper storage conditions, exceeds specimen stability guidelines, contaminated sample.
Result Information
Methodology
Spectrophotometry (SP)
Testing Laboratory
N/A
Reference Range
See Report
Setup Schedule / Expected Turnaround Time
24/7; Report available: Daily