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                      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^L

**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 ^^^^
^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^