Cryptococcus Antigen Rapid Test Cassette (Whole Blood/Serum/Plasma/ Cerebral Spinal Fluid (CSF))
The Cryptococcus Antigen Rapid Test is for the qualitative detection of the capsular polysaccharide antigen of Cryptococcus species complex (Cryptococcus neoformans and Cryptococcus gattii) in specimen to aid in the diagnosis of cryptococcosis.
A rapid test for the qualitative detection of the capsular polysaccharide antigen in whole blood, serum, plasma or cerebral spinal fluid (CSF). For professional in vitro diagnostic use only.
The Cryptococcus Antigen Rapid Test Cassette (Whole Blood/Serum/Plasma/CSF) is a rapid chromatographic immunoassay for the qualitative detection of the capsular polysaccharide antigen of Cryptococcus species complex (Cryptococcus neoformans and Cryptococcus gattii) in whole blood, serum, plasma or cerebral spinal fluid (CSF) to aid in the diagnosis of cryptococcosis.
Cryptococcosis is a cosmopolitan infectious disease of man which begins as a primary infection of the lungs and which may spread to the central nervous system in susceptible subjects. (1) Cryptococcal meningitis (CM), a late and disseminated form of cryptococcal disease, results in substantial morbidity and mortality among HIV-infected individuals.(2) The disease is encountered more frequently in patients with Hodgkin's disease, lymphosarcoma, leukemia and diabetes, and in those receiving prolonged therapy with ste/roids.(1) WHO recommended (LFA) for the diagnosis and screening of infection with cryptococcal antigen.(3)
The Cryptococcus Antigen Rapid Test Cassette (Whole Blood/Serum/Plasma/CSF) is a qualitative membrane based immunoassay for the detection of cryptococcus antigens in whole blood, serum, plasma or CSF. In this test procedure, anti-cryptococcal antigen monoclonal antibodies are immobilized in the test line region of the test. After specimen is added to the
specimen well of the cassette, it reacts with cryptococcal antibody coated colloid gold particles in the test. This mixture migrates chromatographically along the length of the test and interacts with the immobilized anti-cryptococcal antigen monoclonal antibodies. If the specimen contains cryptococcal antigens, a colored line will appear in the test line region indicating a positive result.
If the specimen does not contain cryptococcal antigens, a colored line will not appear in this region indicating 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.
The test contains cryptococcusl antibody coated particles and anti-cryptococcus antigen monoclonal antibodies coated on the membrane.
SPECIMEN COLLECTION AND PREPARATION
The Cryptococcus Antigen Rapid Test Cassette can be performed using whole blood (from venipuncture or fingerstick) serum, plasma or CSF.
To collect Fingerstick Whole Blood specimens:
Wash the patient’s hand with soap and warm water or clean with an alcohol swab. Allow to dry.
Massage the hand without touching the puncture site by rubbing down the hand towards the fingertip of the middle or ring finger.
Puncture the skin with a sterile lancet. Wipe away the first sign of blood.
Gently rub the hand from wrist to palm to finger to form a rounded drop of blood over the puncture site.
Add the Fingerstick Whole Blood specimen to the test by using a capillary tube:
Touch the end of the capillary tube to the blood until filled to approximately 80 uL. Avoid air bubbles.
Place the bulb onto the top end of the capillary tube, then squeeze the bulb to dispense the whole blood to the specimen well of the test cassette.
Separate serum or plasma from blood as soon as possible to avoid hemolysis. Use only clear non-hemolyzed specimens.
Testing should be performed immediately after the specimens have been collected. Do not leave the specimens at room temperature for prolonged periods. Serum, plasma and CSF specimens may be stored at 2-8°C for up to 3 days. For long term storage, specimens should be kept below -20°C. Whole blood collected by venipuncture should be stored at 2-8°C if the test is to be run within 2 days of collection. Do not freeze whole blood specimens. Whole blood collected by fingerstick should be tested immediately.
Bring specimens to room temperature prior to testing. Frozen specimens must be completely thawed and mixed well prior to testing. Specimens should not be frozen and thawed repeatedly.
If specimens are to be shipped, they should be packed in compliance with local regulations covering the transportation of etiologic agents.
EDTA K2, Heparin sodium, Citrate sodium and Potassium Oxalate can be used as the anticoagulant for collecting the specimen.
DIRECTIONS FOR USE
Allow the test, specimen, buffer and/or controls to reach room temperature (15-30°C) prior to testing.
1. Bring the pouch to room temperature before opening it. Remove the test cassette from the sealed pouch and use it as soon as possible.
2. Place the cassette on a clean and level surface.
For Serum, Plasma or CSF specimen:
Hold the dropper vertically and transfer 1 drop of serum, plasma or CSF (approximately 40 uL) to the specimen well,then add 1 drop of buffer (approximately 40 uL), and start the timer. See illustration below.
For Venipuncture Whole Blood specimen:
Hold the dropper vertically and transfer 2 drops of whole blood (approximately 80 uL) to the specimen well, then add 1 drop of buffer (approximately 40 uL), and start the timer.
See illustration below.
For Fingerstick Whole Blood specimen:
To use a capillary tube: Fill the capillary tube and transfer approximately 80uL of fingerstick whole blood specimen to the specimen well of test cassette, then add 1 drop of buffer (approximately 40 uL) and start the timer. See illustration below.
3. Wait for the colored line(s) to appear. Read results at 10 minutes. Do not interpret the result after 20 minutes.
Note: It is suggested not to use the buffer, beyond 6 months after opening the vial.
INTERPRETATION OF RESULTS
(Please refer to the illustration above)
POSITIVE:* Two distinct colored lines appear. One colored line should be in the control region (C) and another colored line should be in the test region (T).
*NOTE: The intensity of the color in the test line region (T) will vary depending on the concentration of cryptococcal antigen present in the specimen. Therefore, any shade of color in the test region (T) should be considered positive.
NEGATIVE: One colored line appears in the control region (C). No apparent colored line appears in the test region (T).
INVALID: Control line fails to appear. Insufficient specimen volume or incorrect procedural techniques are the most likely reasons for control line failure. Review the procedure and repeat the test with a new test. If the problem persists, discontinue using the test kit immediately and contact your local distributor.
|Cryptococcus Antigen Rapid Test Cassette