Swab Specimen Bacterial Infection Test Gold Colloidal Method 24 Months Shelf Life

High accuracy One Step Strep A Rapid test strip , quick and easily, swab specimen,gold colloidal method

Product Name: One Step Strep A Rapid Diagnostic test strip

Accessories:

Intended Use:

The Strep A Rapid Test Cassette is a rapid chromatographic immunoassay for the qualitative detection of Strep A antigens from throat swab specimens to aid in the diagnosis of Group A Streptococcal infection.

Summary:

Streptococcus pyogenes is non-motile gram-positive cocci, which contains the Lancefield group A antigens that can cause serious infections such as pharyngitis, respiratory infection, impetigo, endocarditis, meningitis, puerperal sepsis, and arthritis.1 Left untreated, these infections can lead to serious complications, including rheumatic fever and peritonsillar abscess.2 Traditional identification procedures for Group A Streptococci infection involve the isolation and identification of viable organisms using techniques that require 24 to 48 hours or longer.3.4 The Strep A Rapid Test Cassette is a rapid test to qualitatively detect the presence of Strep A antigens in throat swab specimens, providing results within 5 minutes. The test utilizes antibodies specific for whole cell Lancefield Group A Streptococcus to selectively detect Strep A antigens in a throat swab specimen.

TEST PRINCIPLE

The Strep A Rapid Test Dipstick a qualitative, lateral flow immunoassay for the detection of Strep A carbohydrate antigen in a throat swab. In this test, antibody specific to Strep A carbohydrate antigen is coated on the test line region of the test. During testing, the extracted throat swab specimen reacts with an antibody to Strep A that is coated onto particles. The mixture migrates up the membrane to react with the antibody to Strep A on the membrane and generate a color line in the test line region. The presence of this color line in the test line region indicates a positive result, while its absence indicates a negative result. To serve as a procedural control, a colored line will always appear in the control line region, indicating that proper volume of specimen has been added and membrane wicking has occurred.

TEST PROCEDURE

Allow the test, reagents, swab specimen, and/or controls to reach room temperature (15-30°C) prior to testing.

1. Remove the test dipstick from the sealed foil pouch and use it as soon as possible. Best results will be obtained if the test is performed immediately after opening the foil pouch.
2. Hold the Extraction Reagent 1 bottle vertically and add 4 full drops (approximately 240μL) of Extraction Reagent 1 to an extraction tube. Extraction Reagent 1 is red in color. Hold the Extraction Reagent 2 bottle vertically and add 4 full drops (approximately 160μL) to the tube. Extraction Reagent 2 is colorless. Mix the solution by gently swirling the extraction tube. The addition of Extraction Reagent 2 to Extraction Reagent 1 changes the color of the solution from red to yellow. See illustration 1.
3. Immediately add the swab into the extraction tube, agitate the swab vigorously 15 times, Leave the swab in the extraction test tube for 1 minute. See illustration 2
4. Press the swab against the side of the tube and squeeze the bottom of the tube while removing the swab so that most of the liquid stays in the tube. Discard the swab. See illustration 3.
5. With arrows pointing down, place the dipstick into the tube of solution and then start the timer. If the procedure is followed correctly, the liquid should be at or just below the maximum line (MAX) on the test dipstick. See the illustration 4.
6. Wait for the colored line(s) to appear. Read the result at 5 minutes. Do not interpret the result after 10 minutes. See illustration 5

Caution: The above interpreting time is based on room temperature range of 15-30℃. If your room temperature is significantly lower than 15℃, then the interpreting time should be properly increased to 30 minutes.

INTERPRETATION OF RESULTS

Positive:

Two red lines are visible in the result window. The intensity of the test line may be

weaker or darker than that of the control line. This still means a positive result.

Negative:

The control line appears in the result window, but the test line is not visible.

Invalid:

If the control line does not appear in the result window, the test results are INVALID regardless of the presence or absence of the line in the test region.

PERFORMANCE CHARACTERS:

Clinical Study

Using three medical centers for evaluation, a total of 526 throat swabs were collected from patients exhibiting symptoms of pharyngitis. Each swab was rolled onto a sheep blood agar plate, and then tested by the Strep A Rapid Test Dipstick (Throat Swab). The plates were further streaked for isolation, and then incubated at 37℃ with 5-10% CO2 and a Bacitracin disk for 18-24 hours. The negative culture plates were incubated for an additional 18-24 hours. Possible GAS colonies were subcultured and confirmed with a commercially available latex agglutination grouping kit. Of the 526 total specimens, 404 were confirmed to be negative and 122 were confirmed to be positive by culture. During this study, one Strep F specimens yielded positive results with the Test. One of these specimens was re-cultured, then re-tested and yielded a negative result. Three additional different Strep F strains were cultured and tested for cross-reactivity and also yielded negative results.

Relative Sensitivity: 95.2% (95%CI:*89.6%-98.2%)

Relative Specificity: 97.8% (95%CI:*95.8%-99.0%)

Overall accuracy: 97.2% (95%CI:*95.3%-98.4%) *Confidence Intervals

NOTE: Insufficient specimen volume or incorrect procedural techniques are the most likely reasons for the control line failure. Review the procedure and repeat the test with a new device. If problem persists, please contact your local distributor.