Group A streptococcus (Strep A) Test Kit (Colloidal Gold Method)

【Product Name】 Group A streptococcus (Strep A) Test Kit (Colloidal Gold Method)

【Packing Specifications】 25 servings/box

【Intended Use】

Strep A Test Kit is a rapid and convenient immunochromatographic assay for the qualitative detection of Group A streptococcus (Strep A) antigen from patient throat swab specimens. It is intended for professional use as an aid in the diagnosis of Strep A infection. This assay provides only a preliminary result. Clinical expertise and professional judgment should be sought to further evaluate the result of the test.

【Test Principle】

Streptococcus pyogenes is non-motile gram-positive cocci and known as Group A Streptococcus. The bacteria cause serious acute upper respiratory tract infections such as pharyngitis, respiratory infection, impetigo, endocarditis, meningitis, sepsis and arthritis. Identification procedures in laboratory for Strep A infection involve isolation of viable organisms, followed by various biochemical, microbiological (cell culture) or molecular biology techniques that usually require 24 to 48 hours or even longer. Early diagnosis and treatment of Group A Streptococcal pharyngitis has been shown to reduce the severity of symptoms and further complications such as rheumatic fever and glomerulonephritis. Strep A Test detects either viable or nonviable organisms directly from a throat swab, providing results within 10 minutes.

The test is an antigen-capture immunochromatographic assay, which detects the presence of Strep A in throat swab samples. Monoclonal antibodies specifically against Strep A are 1) conjugated with colloidal gold and deposited on the conjugate pad and 2) immobilized on the test line of the nitrocellulose membrane. When adequate volumes of the test sample is added the antibody conjugate is rehydrated and the Strep A, if any in the samples, will interact with the colloidal gold conjugated antibodies. The antigen-antibody-gold complex will migrate towards the test window until the Test Zone (T) where they will be captured by immobilized antibodies, forming a visible pink line (Test band), indicating a positive result. If Strep A are absent in the sample, no pink line will appear in the Test Zone (T), indicating a negative result.

To serve as an internal process control, a control line should always appear at Control Zone (C) after the test is completed. Absence of a pink control line in the Control Zone is an indication of an invalid result. The detection limit of Strep A Test Kit is approximately 105 Group A Streptococci organism.

【Main components】

1.   Pouch contents: Test cassette, desiccant, sample dropper.

2.   Sample extraction buffer A (7 ml per bottle for 25 tests), buffer B (8 ml per bottle for 25 tests).

3.   Test instruction.

【Storage and stability】

1.   Test device in the sealed pouch should be stored at 2~30°C. Do not freeze the test device.

2.   The bottle containing the buffer should be stored at 2~30°C.

3.   The test device should be kept away from direct sunlight, moisture and heat.

【Sample requirements】

1.   Swab the posterior pharynx, tonsils and other inflamed areas (Note: avoid touching the tongue, cheeks and teeth with the swab).

2.   A specimen should be collected by standard throat swab collection methods. It is preferable to use dacrontipped sterile swab with plastic shafts. Swabs should be processed as soon as possible after collection. If swabs are not processed immediately, they should be placed into a sterile, dry, tightly capped tube or bottle. Swabs which have been transported in liquid media such as modified Stuart's Transport Medium may be used in the test provided the liquid medium has a volume of 1 ml or less. Do not use semisolid transport media containing charcoal. Specimen swabs may be refrigerated (2-8 °C) for up to 5 days. If a culture is desired, lightly roll the swab tip onto a Group A selective blood agar plate before using the swab in the Strep A Rapid Test Device

3.   Add three full drops (85 µl) of specimen without air bubbles into the sample well that is marked with an arrow on the testing device.

Diagnostic Sensitivity = 96.55%

Diagnostic Specificity = 98.08%

Accuracy = 97.16%

【Limitations of the inspection method】

1.   Humidity and temperature can adversely affect results.

2.   The instructions for the use of the test should be followed during testing procedures.

3.   There is always a possibility that false results will occur due to the presence of interfering substances in the specimen or factors beyond the control of the manufacturer, such as technical or procedural errors associated with the testing.

4.   Although the test demonstrates superior accuracy in detecting Strep A, a low incidence of false results can occur. Therefore, other clinically available tests are required in case of questionable results. As with all diagnostic tests, a definitive clinical diagnosis should not be based on the results of a single test but should only be made by the physician after all clinical and laboratory findings have been evaluated.

【Precautions】

1.   For professional in vitro diagnostic use only. Do not reuse.

2.   Do not use if the product seal or its packaging is compromised.

3.   Do not use after the expiration date shown on the pouch.

4.   Do not mix and interchange different specimens.

5.   Wear protective clothing such as laboratory coats, disposable gloves and eye protection while handling potentially infectious materials or performing the assay.

6.   Wash hands thoroughly after finishing the tests.

7.   Do not eat, drink or smoke in the area where the specimens or kits are handled.

8.   Clean up spills thoroughly with appropriate disinfectants.

9.   Handle all specimens as if they contain infectious agents. Observe established precautions against microbiological hazards throughout testing procedures.

10. Dispose of all specimens and used devices in a proper bio-hazard container. The handling and disposal of the hazardous materials should follow local, national or regional regulations.

11. Keep out of children's reach.