TSH Examination Procedure
1.Purpose of examination: TSH assay is a Chemiluminescent Microparticle Immunoassay (CMIA) for the quantitative determination of human Thyroid Stimulating Hormone (TSH) in human serum and plasma.
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:
- Microparticles
- Conjugate
- Multi Assay manual dilution
- Pre trigger solution
- Trigger solution
- Wash-buffer
6.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
- Reagent Storage and stability
- Unopened reagent stable at 15-30°C until expiration date.
- On board System temperature reagent is stable for 28 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:
- ARCHITECT TSH Calibrators
- 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 aliquots.
- 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: Bio Rad Level 1 ,2 & 3 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: The ARCHITECT TSH assay is an automated two-step immunoassay to determine the presence of Thyroid Stimulating Hormone (TSH) in human serum and plasma using CMIA technology with flexible assay protocols, referred to as Chemiflex.
- Sample, anti-β TSH antibody coated paramagnetic microparticles and TSH Assay Diluent are combined. TSH present in the sample binds to the anti-TSH antibody coated microparticles.
- After washing, anti-α TSH acridinium-labeled conjugate is added to create a reaction mixture.
- Following another wash cycle, Pre-Trigger and Trigger Solutions are added to the reaction mixture.
- The resulting chemiluminescent reaction is measured as relative light units (RLUs). There is a direct relationship between the amount of TSH in the sample and the RLUs detected by the ARCHITECT iSystem optics.
10.Sample Preparation:
- Required SampleVolume: 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: 0.0038 μIU/mL to 100.0000 μIU/mL. The limit of detection (LOD) : ≤ 0.4 ng/dL. The limit of quantification(LOQ): 0.28 ng/dL Unit:ng/dL.
Normal and critical ranges:
Thyrotropin (thyroid-stimulating hormone) (TSH)
Birth-4 d | 1.0-39.0 | µIU/mL |
---|---|---|
2-20 wk | 1.7-9.1 | µIU/mL |
21 wk-20 y | 0.7-6.4 | µIU/mL |
21-54 y | 0.4-4.2 | µIU/mL |
55-87 y | 0.5-8.9 | µIU/m |
12.Laboratory Clinical interpretation: The common causes of High TSH Level are as follows: Hypothyroidism The common causes of LowTSH Level are as follows:Primary Hyperthyroidism
13.Interference and cross reaction: TSH assay is designed to have a potential interference from hemoglobin, bilirubin, triglycerides and protein of ≤ 10% at the levels indicated below.
Hemoglobin | ≤ 500 mg/dL |
---|---|
Bilirubin | ≤ 20 mg/dL |
Triglycerides | ≤ 3000 mg/dL |
Protein | ≤ 2 g/dL and 12 g/dL |
14.Potential source of variation: Turn around time (TAT): Routine: 6.0 hours Urgent: 2.0 hours
15.Recording of observation: Software backup Machine raw data
16.Storage & Disposal of waste: Follow storage & discard procedure
17.Environmental & Safety control: Contact with acids liberates very toxic gas. Dispose of contents / container in accordance with local regulations.
18.References:
- Tietz NW, Huang WY, Rauh DF, et al. Laboratory tests in the differential diagnosis of hyperamylasemia. Clin Chem 1986 32(2):301-307
- 6 Junge W. Troge B, Klein G, et al. Evaluation of a New Assay for Pancreatic Amylase: Performance Characteristics and Estimation of Reference Intervals Clin Biochem 1989,22 109-114
- Stuttgart/New York Georg Thieme Verlag 1991 354-361. 3 Salt WB II, Schenker S. Amylase its clinical significance: a review ofthe literature [Review] Medicine 1976,55 269-281.
- 4 Steinberg WM, Goldstein SS, Davies ND, et al. Diagnostic assays in acute pancreatitis [Review]. Ann Intern Med 1985,102.576-580
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 | |||
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Document No.1 | Document Name: TSH 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 |