Creatinine Plus in Human Serum with Roche c502

Detection of Creatinine Plus in Human Serum with Roche c502

Test Name: In vitro test for the quantitative determination of creatinine plus in human serum and plasma on Roche/Hitachi cobas c systems.
Method Name: The enzymatic method is based on the conversion of the substrate into glycine, formaldehyde, and hydrogen peroxide. Liberated hydrogen peroxide will react to form a quinone imine chromogen. The color intensity is directly proportional to the creatinine concentration in the reaction mixture.
Results: Technical Range: 0.06-30.5 mg/dL
Reportable Range: 0.08-26.99 mg/dL
Reference Ranges: Serum/Plasma
For adult men: 0.74 to 1.35 mg/dL
For adult women: 0.59 to 1.04 mg/dL
Clinical Significance: Chronic kidney disease is a worldwide problem that carries a substantial risk for cardiovascular morbidity and death. Current guidelines define chronic kidney disease as kidney damage or glomerular filtration rate (GFR) less than 60 mL/min per 1.73 m2 for three months or more, regardless of cause.

The assay of creatinine in serum or plasma is the most commonly used test to assess renal function.

Creatinine is a break-down product of creatine phosphate in muscle and is usually produced at a fairly constant rate by the body (depending on muscle mass). It is freely filtered by the glomeruli and, under normal conditions, is not re-absorbed by the tubules to any appreciable extent. A small but significant amount is also actively secreted.

Since a rise in blood creatinine is observed only with marked damage of the nephrons, it is not suited to detect early-stage kidney disease.

In addition to the diagnosis and treatment of renal disease, the monitoring of renal dialysis, creatinine measurements are used for the calculation of the fractional excretion of other urine analytes (e. g., albumin, α amylase).

Submission Criteria: For specimen collection and preparation, only use suitable tubes or collection containers.
Only the specimens listed below were tested and found acceptable.
Plasma: Li-heparin and K2-EDTA plasma

The sample types listed were tested with a selection of sample collection tubes that were commercially available at the time of testing, therefore not all available tubes of all manufacturers were tested. Sample collection systems from various manufacturers may contain differing materials which could affect the test results in some cases.  When processing samples in primary tubes (sample collection systems), follow the instructions of the tube manufacturer.

Storage and Stability

Serum and Plasma:       7 days at 15-25°C
7 days at 2-8°C
3 months at (-15°C) – (-25°C)

Rejection Criteria: Rejection criteria include but are not limited to:
1. Specimens containing fibrin or clots.
2. Excessive platelet clumping
3. Leaking specimens
4. Substandard mixing or collection
5. Expired or improperly stored collection tubes.
6. Improperly filled tubes based on collection tube manufacturer’s guidelines.
7. Contaminated specimens (IV fluid, foreign particles, etc.)
8. Specimens not analyzed within the appropriate time frame.
9. Samples not shipped at appropriate temperature.
10. Samples without 2 proper identifiers or samples having identifiers that do not match the electronic or paper lab requisition.
Authorization: Diagnostic testing can only be performed with approval from an authorized provider/agency.
Turn Around Time: 1 day.