creatinine [Laboratory Service Sir T Hospital , Bhavnagar ]

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                       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:** 
  - Type of Sample: Serum,  Plasma
  - Type of container and additives: Plain without any additives 
  - Patient Preparation: As per Primary Sample Collection Manual [[sample_collection_manual|]]
  - Stability: At Room temperature 18°–28°C (64°–82°F) stability ≤ 24 hours
  - Handling and transport: As per Primary Sample collection manual 
  - 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:**
  - Start the equipment.WDI abbotte fully.docx
  - Calibrators are ready to use.
  - Put calibrator 15-20 minutes at room temperature  
  - Prior to use, mix the contents by inverting the vial. Do not shake the vial to prevent foam formation. 
  - Take a 150 µl calibrator solution in to separate aliquot.
  - Go to the calibration and give the calibration order.
  - Verify calibration with at least two levels of controls
  - 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** 
  - Reconstitution of QC material with 5 ml Distilled water by using calibrated fixed volume pipette.
  - Leave to stand for 30 min in the dark place.
  - Swirl gently several times during the reconstitution period to ensure that the contents are completely dissolved.
  - 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.
  - Prepare aliquots of 150 µl from the reconstituted QC material.
  - Store these aliquots at -15° C to -20° C.
  - Prior to use, make sure that aliquots should be at room temperature for at least 15 min.

**Procedure to run IQC**
  - Press Control order 
  - Select Assay /Panel, to be run.
  - Select the control/s and its level/s
  - Give Carrier Number and Position number
  - Press F3 / Add order
  - Put respected carrier in RSH rack
  - 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**
  - Press Patient order 
  - Select Assay /Panel, to be run.
  - Give Carrier Number and Position number
  - Press F3 / Add order
  - 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:**

^1-5 y^0.04-0.45^mg/dL^
^6-10 y^0.22-0.59^mg/dL^
^Adult male^0.62-1.10^mg/dL^
^Adult Female^0.45-0.75^mg/dL^

**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:**
  - Wear protective gloves / protective clothing / eye protection
  - Do not breathe mist / vapors / spray
  - Wash hands thoroughly after handling
  - Keep only in original container

**20.Response**
  - IF SWALLOWED: Rinse mouth. Do NOT induce vomiting
  - IF IN EYES:Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do.Continue rinsing
  - 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:**
  - Thomas L, editor. Clinical Laboratory Diagnostics: Use and Assessment of Clinical Laboratory Results. Frankfurt, Germany: TH- Books Verlagsgesellschaft mbH; 1998:366–374.
  -  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.
  - Folin O. Beitrag zur Chemie des Kreatinins und Kreatins Im Harne.Hoppe Seylers Z Physiol Chem 1904;41:223–242.
  - Fabiny DL, Ertingshausen G. Automated reaction-rate method for determination of serum creatinine with the CentrifiChem. Clin Chem 1971;17:696–700.
  - 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.

|**Printed copy of this document is considered uncontrolled.** It should be compared with controlled electronic copy before use|

^ Name of Laboratory : Laboratory Services Sir T. Hospital (LSSTH),Bhavnagar ^^^^
^Document No.1^**Document Name**: Creatinine Examination Procedure^**Unique ID**:LSSTH /BIOCHEM/ SOP-5^^
^Issue No. : 01^Issue Date :30/04/2024^Page No.^^
^Amend No.^ Amend Date ^Prepared by: Section Incharge^Approved & Issued by: HOD,Biochemistry^