QUICKVUEFLEX

STREP A TEST

INTENDED USE

The QuickVue Flex Strep A Test allows for The QuickVue Flex Strep A Test allows for the rapid detection of group A streptococcal the rapid detection of group A streptococcal antigen directly from the patient throat swab antigen directly from the patient throat swab specimens. The test is intended for use as specimens. The test is intended for use as an aid in the diagnosis of group A an aid in the diagnosis of group A streptococcal infection.streptococcal infection.

BACKGROUND

Group A beta-Group A beta-hemolytic hemolytic streptococci streptococci (Streptococcus (Streptococcus pyogenes) is one of pyogenes) is one of the most commonly the most commonly encountered encountered pathogens in pathogens in humans.humans.

BACKGROUND (cont.)

Group A Group A StreptococcusStreptococcus inhabits the skin and inhabits the skin and upper respiratory tract of humans but is rarely upper respiratory tract of humans but is rarely considered as normal flora. It is transmitted considered as normal flora. It is transmitted person to person by direct contact with mucosa, person to person by direct contact with mucosa, secretions or by contamination droplets produced secretions or by contamination droplets produced by coughs or sneezes. The presence of Group A by coughs or sneezes. The presence of Group A StreptococcusStreptococcus is almost always considered is almost always considered clinically significant.clinically significant.

BACKGROUND (cont.)

When present, Group A Streptococcus can When present, Group A Streptococcus can cause a variety of illnesses. It is the most cause a variety of illnesses. It is the most common cause of skin infections such as common cause of skin infections such as impetigo and erysipelas. It can cause impetigo and erysipelas. It can cause illness such as tonsillitis, pharyngitis, and illness such as tonsillitis, pharyngitis, and scarlet fever which can lead to more serious scarlet fever which can lead to more serious complications including rheumatic fever complications including rheumatic fever and acute glomerulonephritis.and acute glomerulonephritis.

BACKGROUND (cont.)

Group A Group A StreptococcusStreptococcus has also been called has also been called “ flesh eating bacteria” because of it’s “ flesh eating bacteria” because of it’s ability to progress into deeper tissue and ability to progress into deeper tissue and organs which can cause systemic and life organs which can cause systemic and life threatening infections.threatening infections.

BACKGROUND (cont.)

Early diagnosis and treatment of Group A Early diagnosis and treatment of Group A StreptococcusStreptococcus infections is therefore very infections is therefore very important and helps to prevent further important and helps to prevent further complications of many of the previously complications of many of the previously mentioned illnesses. The QUICKVUE FLEX mentioned illnesses. The QUICKVUE FLEX Strep A Test is a rapid screening test used for the Strep A Test is a rapid screening test used for the detection consumes little time when compared detection consumes little time when compared with the 24-48 hours waiting period of more with the 24-48 hours waiting period of more conventional methods that require microscopic conventional methods that require microscopic examination, culture, and isolation of the bacteria.examination, culture, and isolation of the bacteria.

PRINCIPLES OF THE TEST

THE QUICKVUE FLEX Strep A Test is a lateral-THE QUICKVUE FLEX Strep A Test is a lateral-flow immunoassay. The test, containing a highly flow immunoassay. The test, containing a highly specific and sensitive antibody reactive to the specific and sensitive antibody reactive to the Strep A antigens, is specific to Group A. To Strep A antigens, is specific to Group A. To perform the test, a throat swab specimen is perform the test, a throat swab specimen is collected. The extraction reagents are mixed in a collected. The extraction reagents are mixed in a tube, resulting in a green color change, and the tube, resulting in a green color change, and the swab is added in order for the antigenic swab is added in order for the antigenic component of the bacteria to be extracted.component of the bacteria to be extracted.

PRINCIPLES OF THE TEST (cont.)

Extraction occurs within one minute, after which the Extraction occurs within one minute, after which the extracted sample is added to the Sample Well of the Test extracted sample is added to the Sample Well of the Test Cassette. The extracted sample migrates by capillary Cassette. The extracted sample migrates by capillary action through a pad consisting of a pink label containing action through a pad consisting of a pink label containing rabbit polyclonal anti-strep A antibody and a blue control rabbit polyclonal anti-strep A antibody and a blue control label. If the extracted solution contains strep A antigen, label. If the extracted solution contains strep A antigen, the antigen will bind to the antibody coupled to the pink the antigen will bind to the antibody coupled to the pink test label which, in turn, will bind a second rabbit test label which, in turn, will bind a second rabbit polyclonal anti strep A antibody spotted on the membrane, polyclonal anti strep A antibody spotted on the membrane, resulting in the formation of a pink-to-purple Test line.resulting in the formation of a pink-to-purple Test line.

PRINCIPLES OF THE TEST (cont.)

A blue Control Line will also appear next to the A blue Control Line will also appear next to the letter “C” on the Test Cassette indicating that the letter “C” on the Test Cassette indicating that the reagents were mixed and added properly, proper reagents were mixed and added properly, proper volume of fluid entered the Test Cassette and volume of fluid entered the Test Cassette and capillary flow occurred. A blue Control Line capillary flow occurred. A blue Control Line should always appear in a properly functioning should always appear in a properly functioning Test Cassette. If strep A is not present or present Test Cassette. If strep A is not present or present at very low levels, only a blue Control Line will at very low levels, only a blue Control Line will be visible.be visible.

REAGENTS & MATERIALS

Come in individually packaged Test CassettesCome in individually packaged Test Cassettes Rabbit polyclonal antibody to strep A (Test Line) Rabbit polyclonal antibody to strep A (Test Line)

and a control rabbit polyclonal antibody capable of and a control rabbit polyclonal antibody capable of binding the blue control label (Control Line)binding the blue control label (Control Line)

– EXTRACTION REAGENT AEXTRACTION REAGENT A– ( 4M Sodium Nitrite)( 4M Sodium Nitrite)– EXTRACTION REAGENT BEXTRACTION REAGENT B– (.2M Acetic Acid) (.2M Acetic Acid) – Sterile rayon-tipped swabs on solid plastic shaftsSterile rayon-tipped swabs on solid plastic shafts– Tubes and tipsTubes and tips– Positive Control SwabsPositive Control Swabs– Negative Control SwabsNegative Control Swabs– Package InsertPackage Insert– Procedure CardProcedure Card

TEST PROCEDURE

Streak a BAP prior to beginning the Streak a BAP prior to beginning the extraction procedure.extraction procedure.

For each specimen and control:For each specimen and control: Add 4 drops of Extraction Reagent A Add 4 drops of Extraction Reagent A

into a clean Tubeinto a clean Tube Add 4 drops of Extraction Reagent B. Add 4 drops of Extraction Reagent B.

The solution should turn green when The solution should turn green when Extraction Reagent B is added.Extraction Reagent B is added.

PROCEDURE, cont.

Immediately add the Immediately add the throat swab throat swab specimen to the Tube specimen to the Tube containing the green containing the green extraction solution. extraction solution.

Rotate the swab Rotate the swab three times.three times.

Wait one minute.Wait one minute.

PROCEDURE, cont.

Express all liquid from Express all liquid from the swab head in the Tube the swab head in the Tube by rolling the swab by rolling the swab against the inside of the against the inside of the Tube and squeezing Tube and squeezing firmly as it is withdrawn.firmly as it is withdrawn.

Discard the swab.Discard the swab.

PROCEDURE, cont.

Put a clean tip on Put a clean tip on the Tube. the Tube.

PROCEDURE, cont.

Remove Test Remove Test Cassette from foil Cassette from foil pouch and place on pouch and place on a clean, dry surface.a clean, dry surface.

Add 2 drops from Add 2 drops from the Tube to the the Tube to the round Sample Well round Sample Well on the Test on the Test CassetteCassette..

PROCEDURE, cont.

Read results at 5 minutes. Some positive Read results at 5 minutes. Some positive results may be seen earlier, but negative results may be seen earlier, but negative results must be held the entire 5 minutes results must be held the entire 5 minutes and no longer.and no longer.

INTERPRETATION OF RESULTS

Positive results: Positive results: appearance of any pink to appearance of any pink to purple Test Line next to purple Test Line next to the “T” in the result the “T” in the result window.window.

Positive QuickVue Flex Positive QuickVue Flex Strep A Test result Strep A Test result indicates that the indicates that the specimen contains group specimen contains group A streptococcal antigen.A streptococcal antigen.

INTERPRETATION OF RESULTS (cont.)

Negative Result: Negative Result: Only the blue Control Only the blue Control Line appears next to Line appears next to the letter “C” in the the letter “C” in the Result Window.Result Window.

INTERPRETATION OF RESULTS (cont.)

A negative QuickVue Flex Strep A Test A negative QuickVue Flex Strep A Test result indicates that the specimen is a result indicates that the specimen is a presumptive negative for the presence of presumptive negative for the presence of group A streptococcal antigen, pending the group A streptococcal antigen, pending the result of the BAP streaked prior to the result of the BAP streaked prior to the beginning of the extraction procedure.beginning of the extraction procedure.

INVALID RESULT

The test result is The test result is invalid if any shade invalid if any shade of blue Control Line of blue Control Line next to the letter “C” next to the letter “C” is not visible at 5 is not visible at 5 minutes. If this minutes. If this occurs, retest using a occurs, retest using a new specimen and a new specimen and a new Test Cassette.new Test Cassette.

PROCEDURE LIMITATIONS

This procedure used for qualitative detection of This procedure used for qualitative detection of group A streptococcal antigen from throat swab group A streptococcal antigen from throat swab specimen only. Failure to follow the test specimen only. Failure to follow the test procedure and interpretation of test results may procedure and interpretation of test results may adversely affect performance and /or produce adversely affect performance and /or produce invalid results. invalid results.

PROCEDURE LIMITATIONS QuickVue Flex Strep A Test will not QuickVue Flex Strep A Test will not

differentiate asymptomatic carriers of group differentiate asymptomatic carriers of group A A StreptococcusStreptococcus from those exhibiting from those exhibiting streptococcal infection. In rare cases, test streptococcal infection. In rare cases, test specimens heavily colonized with specimens heavily colonized with StaphylococcusStaphylococcus aureusaureus can yield false can yield false positive results. positive results.

PROCEDURE LIMITATIONS

A negative test result might occur if the level of A negative test result might occur if the level of extracted antigen in a sample is below the extracted antigen in a sample is below the sensitivity of the test. Additional follow-up sensitivity of the test. Additional follow-up testing using the culture method is recommended testing using the culture method is recommended if the QuickVue test result is negative.if the QuickVue test result is negative.

CONCLUSION

QUICKVUE FLEX TEST:QUICKVUE FLEX TEST: Is a rapid, specific and sensitive test for detection of Is a rapid, specific and sensitive test for detection of

Group A Group A StreptococcusStreptococcus ( ( Streptococcus pyogenesStreptococcus pyogenes) ) antigen directly from patient throat swab specimen.antigen directly from patient throat swab specimen.

It allows the physician to do quick diagnoses based on It allows the physician to do quick diagnoses based on the results.the results.

It avoids the 24-48 hours incubation time for blood It avoids the 24-48 hours incubation time for blood culture plate tests.culture plate tests.

This test is much more expensive than blood agar.This test is much more expensive than blood agar.