Umdnj robert wood johnson medical school point of care testing program

The QuickVue In-Line Strep A test uses color immunochromatographic technology with rabbit antibodies coated on the nitrocellulose membrane. In the test procedure, a throat swab is subjected to a chemical extraction of a carbohydrate antigen unique to Group A Streptococcus. The Lab Strip is then placed in the extraction mixture and the mixture migrates along the membrane. If Group A Strep is present in the sample, it will form a complex with the anti-Group A streptococcus antibody conjugated color particles. The complex will then be bound by the anti-Group A Streptococcus capture antibody and a visible pink-to-purple Test line will appear to indicate a positive result.

Clinical Significance:

Reagents And Materials

25 Individually packaged Test Cassettes

25 Extraction Solution bottles

25 Individually packaged Sterile Rayon-Tipped Swabs

1 Positive control Swab (Heat-inactivated Group A streptococcus)

1 Negative control Swab (Heat-inactivated Group C streptococcus)

Store LabStrips and reagents tightly capped at room temperature (59-86F)

1 Extraction Kit (For use with Proficiency Testing Samples only)

The QuickVue In-Line Strep A test contains built-in control features. There is a two-color result format that provides clear-cut readout for positive and negative results. The appearance of a blue Control Line next to the letter “C” ensures the functional activity of the cassette. If the blue line does not appear within five minutes, the test result is invalid.

Each kit contains positive and negative control swabs. These controls are used ensure that the extraction reagents and the testing strips are functioning properly and to insure that the procedure is being performed correctly by testing personnel.

Quality Control Test Procedure (Gloves should be worn)

1. 
   Remove the Positive or Negative Control Swab from its container and insert it completely into the QuickVue In-Line Strep A Test Cassette Swab Chamber.
   
2. 
   Squeeze ONCE to break the glass ampule inside the extraction solution bottle.
   
3. 
   Vigorously shake the Bottle five times to mix the solutions. Solution should turn green after the ampule is broken. Solution should be used immediately.
   
4. 
   Remove the cap. Quickly fill the chamber to the rim (approximately 10 drops). Begin timing. If liquid has not moved across the Result Window in one minute, completely remove the swab and re-insert. If liquid still does not move across, retest with a new control, Test Cassette and Extraction Bottle. The Test Cassette should not be moved until the assay is complete.
   
5. 
   Read results at five minutes.
   

1. 
   Place a clean tube from the Extraction Kit in a test tube rack.
   
2. 
   Squeeze to crush the glass ampule inside the Extraction Solution Bottle as described above (#2).
   
3. 
   Dispense eight (8) drops from the Extraction Solution Bottle into the tube. Place the proficiency swab into the tube. Hold the bottom of the tube so that the swab head is slightly compressed. Rotate the swab three times.
   
4. 
   WAIT ONE MINUTE.
   
5. 
   Express ALL liquid from the swab head in the tube by rolling the swab against the inside of the tube and pressing slightly as it is withdrawn from the tube. Discard the swab.
   
6. 
   Fill the Disposable Dropper to the fill line with solution from the tube and add the contents into the Test Cassette Swab Chamber.
   
7. 
   Read the results at five (5) minutes. See above (#5 of Quality Control section) to read the results.
   

• 
  Gloves should be worn when handling specimens.
  
• 
  Collect specimens only with the sterile rayon-tipped swab supplied in the kit, from the tonsil and /or back of the throat. Take care to avoid the teeth, gums, and tongue or cheek surfaces.
  
• 
  Process the swab as soon as possible after collecting the specimen.
  
• 
  The swabs and the test kit must be at room temperature before starting the test.
  

1. 
   Remove the Test Cassette from foil pouch and place on a clean, dry, level surface.
   
2. 
   Using the notch at the back of the chamber as a guide, insert the Rayon-Tipped Swab completely into the Swab Chamber.
   
3. 
   Squeeze ONCE to break the glass ampule inside the extraction solution bottle.
   
4. 
   Vigorously shake the Bottle five times to mix the solutions. Solution should turn green after the ampule is broken. Solution should be used immediately.
   
5. 
   Remove the cap. Quickly fill the chamber to the rim (approximately 10 drops). Begin timing. If liquid has not moved across the Result Window in one minute, completely remove the swab and re-insert. If liquid still does not move across, retest with a new control, Test Cassette and Extraction Bottle. The Test Cassette should not be moved until the assay is complete.
   
6. 
   Read results at five minutes. Some positive results may be seen earlier.
   

• 
  The results obtained with this kit yield data that must be used only as an adjunct to other information available to the physician.
  
• 
  The quality of the test depends on the quality of the sample; proper throat swab specimens must be obtained.
  
• 
  This test does not differentiate between carriers and acute infections. Pharyngitis may be the result of infection with organisms other than streptococcus.
  
• 
  A negative result may be obtained if the specimen is inadequate or the antigen concentration is below the sensitivity of the test.
  
• 
  A negative Signify Strep A test result should be followed up by a culture and sent to the laboratory.
  

If you require assistance, please contact your POCT site supervisor, the UMDNJ - Robert Wood Johnson Medical School POCT coordinator, or the UDL central administrative office.

References

Written by: ______ UMG POCT Committee. Date: _____01/15/02____