Creatinine Examination Procedure 

1.Purpose of examination:

• Creatinine estimation from serum or plasma by Kinetic Alkaline Picrate Method.

2.Responsibility and Authority:

• Calibration: Technician
• Quality Control: Technician
• Routine operation: Technician
• Overall Monitoring: Quality Manager

3.Sample Details:

1. Type of Sample: Serum, Plasma
2. Type of container and additives: Plain without any additives
3. Patient Preparation: As per Primary Sample Collection Manual sample_collection_manual
4. Stability: At Room temperature 18°–28°C (64°–82°F) stability ≤ 24 hours
5. Handling and transport: As per Primary Sample collection manual
6. Storage: 24 hours at 2-8° C

4.Required Equipment:

• Centrifuge, Auto-Pipette, Disposable Tips, Disposable sample cups, FullyAuto Chemistry Analyzer

5.Required reagents:

• R1. Sodium hydroxide 0.8 mol/L
• R2. Picric acid 24 mmol/L
• Reagent Handling
• Remove any air bubbles present in the reagents with a new applicator stick, or allow the reagents to settle at the appropriate storage temperature to allow the bubbles to dissipate. To minimize volume depletion, do not use a transfer pipette to remove bubbles

6.Reagent Storage and stability:

• Unopened reagent stable at 15-30°C until expiration date.
• On board System temperature reagent is stable for 05 days
• Instability or deterioration should be suspected if there are precipitates, visible signs of leakage or contamination, turbidity, or if calibration or controls do not meet the appropriate criteria.

7.Calibration Procedure:

• Consolidated Chemistry Calibrators(ConCC)
• Frequency:
• Reagent lot change
• QC out of range
• After service or maintenance
• Replacement in any parts of Instrument

Procedure:

1. Start the equipment.WDI abbotte fully.docx
2. Calibrators are ready to use.
3. Put calibrator 15-20 minutes at room temperature
4. Prior to use, mix the contents by inverting the vial. Do not shake the vial to prevent foam formation.
5. Take a 150 µl calibrator solution in to separate aliquot.
6. Go to the calibration and give the calibration order.
7. Verify calibration with at least two levels of controls
8. If control results fall outside acceptable ranges,root cause analysis or recalibration may be necessary.

8.Quality control Procedure:

Name: Biorad Level 1 &2

Frequency: As per Quality Control Procedure

Procedure for Reconstitution of IQC

1. Reconstitution of QC material with 5 ml Distilled water by using calibrated fixed volume pipette.
2. Leave to stand for 30 min in the dark place.
3. Swirl gently several times during the reconstitution period to ensure that the contents are completely dissolved.
4. Prior to use, mix the contents by inverting the vial. Do not shake the vial as the information of foam should be avoided. Ensure that no lyophilized material remains un-reconstituted.
5. Prepare aliquots of 150 µl from the reconstituted QC material.
6. Store these aliquots at -15° C to -20° C.
7. Prior to use, make sure that aliquots should be at room temperature for at least 15 min.

Procedure to run IQC

1. Press Control order
2. Select Assay /Panel, to be run.
3. Select the control/s and its level/s
4. Give Carrier Number and Position number
5. Press F3 / Add order
6. Put respected carrier in RSH rack
7. Check IQC results, in case outliers call residents.

9.Principle of the procedure used for examinations: At an alkaline pH, creatinine in the sample reacts with picrate to form a creatinine-picrate complex. The rate of increase in absorbance at 500 nm due to the formation of this complex is directly proportional to the concentration of creatinine in the sample.

10.Sample Preparation:

• Required Sample Volume: 150 µl of the sample
• Temperature: 37°

Take 150-200µl of the sample from Primary tube to the secondary aliquot. Write the sample ID on the aliquot.

Procedure to run Patient sample

1. Press Patient order
2. Select Assay /Panel, to be run.
3. Give Carrier Number and Position number
4. Press F3 / Add order
5. Put respected carrier in RSH rack

11.Performance Characteristics:

• Linearity: 0.20 to 37.00 mg/dL
• The limit of detection (LOD): 0.05 mg/dL
• The limit of quantification(LOQ):0.10 mg/dL
• Unit: mg/dl

12.Normal and critical ranges:

13.Laboratory Clinical interpretation:

• Measurement of serum creatinine is used to diagnose and monitor acute and chronic renal disease, estimate glomerular filtration rate (GFR), or assess the status of renal dialysis patients.

14.Interference and cross reaction: The Following analytes were tested up to the levels indicated at Creatinine concentrations of 0.14mg/dl and 5.03 mg/dl, and found not to interfere:

• No interference from Bilirubin up to 30 mg/dL
• No interference from Hemoglobin up to 1,000 mg/dL
• No interference from Intralipid up to 750 mg/dL
• No interference from Ascorbate up to 1.5 mg/dL
• No interference from Glucose up to 300 mg/dL
• No interference from Protein up to 10.6 g/dL

15.Potential source of variation:

• Turn around time (TAT):
• Routine: 6.0 hours
• Urgent: 2.0 hours

16.Recording of observation:

• Software backup
• Machine raw data

17.Storage & Disposal of waste: Follow storage & discard procedure

18.Environmental & Safety control:

Reagent R1 contains sodium hydroxide that Causes severe skin burns and eye Damage & May be corrosive to metals

19.Precautions:

1. Wear protective gloves / protective clothing / eye protection
2. Do not breathe mist / vapors / spray
3. Wash hands thoroughly after handling
4. Keep only in original container

20.Response

1. IF SWALLOWED: Rinse mouth. Do NOT induce vomiting
2. IF IN EYES:Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do.Continue rinsing
3. IF ON SKIN (or hair): Take off immediately all contaminated clothing. Rinse skin with water / shower.

For Reagent R2:

• Explosive when dry
• Picric acid is a flammable solid when wet as a paste (i.e., not less than 10% water), and explosive when dry.
• Prevent from forming crystals.
• Keep containers tightly sealed.
• Do not allow to dry out.

21.References:

1. Thomas L, editor. Clinical Laboratory Diagnostics: Use and Assessment of Clinical Laboratory Results. Frankfurt, Germany: TH- Books Verlagsgesellschaft mbH; 1998:366–374.
2. Jaffe M. Ueber den Niederschlag, welchen Pikrinsaure in normalem Harn erzeugt und uber eine neue Reaction des Kreatinins. Hoppe Seylers Z Physiol Chem 1886;10:391–400.
3. Folin O. Beitrag zur Chemie des Kreatinins und Kreatins Im Harne.Hoppe Seylers Z Physiol Chem 1904;41:223–242.
4. Fabiny DL, Ertingshausen G. Automated reaction-rate method for determination of serum creatinine with the CentrifiChem. Clin Chem 1971;17:696–700.
5. Soldin S, Henderson L, Hill G. The effect of bilirubin and ketones on reaction rate methods for the measurement of creatinine. Clin Biochem 1978:82–86.