HBsAg is one of the earliest markers that appear in the blood following infection with Hepatitis B virus (HBV). This infection of the liver is transmitted by homosexual or heterosexual activity, blood borne exposure, mother-infant, close personal contact and by intake of contaminated water and food products. In the HBV infected people, the virus persists for the rest of their lives and can be passed on to others. Therefore Hepatitis B has become a global public health problem.
Infection with HBV results in the appearance of a number of serological markers and one of the first of such markers is Hepatitis B surface antigen (HBsAg). The HBV infection causes a wide variety of liver damage such as acute self-limiting infection, fulminating hepatitis, chronic hepatitis with progression to cirrhosis and liver failure, and a symptomatic chronic carrier state.
Hepatitis B surface antigen (HBsAg) appears 1-7 weeks before biochemical evidence of liver disease or jaundice. Three weeks after the onset of acute hepatitis, almost half of the patients will still be positive for HBsAg. In the chronic carrier state, the HBsAg persists for long periods (6-12 months) with no seroconversion to the corresponding antibodies. Therefore, screening for HBsAg is highly desirable for all donors, pregnant women and people in high-risk groups.
An immunoassay for the rapid and qualitative detection of Hepatitis B in human whole blood. For in vitro diagnostic use only.
Materials Supplied: Test cassette, Pipette, Diluent, Package insert.
Materials Required but not Supplied: Specimen collection container, Stop watch.
Principle: Hepatitis B Surface Antigen Test Kit is a chromatographic immunoassay (CIA) for the rapid qualitative determination of human hepatitis B surface antigen (HBsAg) in whole blood. The membrane is pre-coated with anti-HBsAg capture antibody on the test band region and Rabbit anti-goat IgG on the control band region. During testing, the specimen is allowed to react with the colloidal gold particles which have been coated with goat-anti-HBsAg. The mixture then moves laterally on the membrane by capillary action. For a positive result, a pink coloured band with a specific antibody-HBsAg-antibody-colloidal gold particle complex will form on the test band region. Absence of coloured band in the test band region indicates a negative result. To serve as a procedural control, a pink coloured band at the control region will always appear regardless the presence of HBsAg.
Performance Characteristcs: Sensitivity: Hepatitis B Surface Antigen Test Kit detects hepatitis B surface antigen (HBsAg) concentration in whole blood specimens higher than 2ng/ml as indicated by the development of a colored band in the test region of the device.
Specificity: Antibodies used for Hepatitis B Surface Antigen Test Kit were raised against whole hepatitis B surface antigen. All subtype Hepatitis B antigens (adr, adw, ayr, ayw) show positive results with Hepatitis B Surface Antigen Test Kit. On the other Hepatologic diseases, patients do not produce positive with Hepatitis B Surface Antigen Test Kit.
Hepatitis B Surface Antigen Test Kit is used for the qualitative determination of hepatitis B surface antigen (HBsAg) in human whole blood. This test is intended for the screening of blood and blood products to be used for transfusion and an aid for the diagnosis of existing or previous hepatitis B infection.
For professional and IN VITRO diagnostic use only.
The test cassette should remain in the sealed pouch until use. Do not use after the expiration date.
There should be no smoking or eating where antigen containing materials are being handled. Wear disposable gloves and lab coat while handling specimens. Wash hands thoroughly afterwards.
Decontaminate and dispose specimens and all potentially contaminated materials if they contain infectious agent.
As with all diagnostic tests, a definitive clinical diagnostic tests should not be based on the results of a single test, but should only be made by the physician after all clinical and laboratory have been evaluated.
Hepatitis B Surface Antigen Test Kit should be stored at room temperature (up to 30°C) in the sealed pouch or desiccated container.
Do not use beyond the expiration date.
Specimen Collection and Storage: 1. Hepatitis B Surface Antigen Test Kit is performed on human whole blood.
2. Remove the whole blood from the clot or red cells, respectively, as soon as possible to avoid hemolysis. Lipemic, icteric, or hemolyzed specimens may give inconsistent test result. Specimens, containing precipitate, should be clarified prior to testing.
3. HBsAg is thermo-labile. If specimens are not to be tested they should be refrigerated immediately at 2 to 8°C, if storage periods greater than 3 days are anticipated, the specimen should be frozen. If specimens are to be shipped, they should be packed in compliance with federal regulations covering the transportation of etiologic agents.
4. Do not use heat-inactive specimens.
Test Procedure: 1. Review specimen collection instructions. Test cassette together with patients samples or controls should be bought to room temperature (20-30°C) prior to testing.
2. Remove the test cassette from its protective pouch (bring the sealed pouch to room temperature before opening to avoid condensation of moisture on the membrane). Label the cassette with patient or control identifications.
3. Use the pipette to withdraw specimen from the specimen collection container and dispense 3 drops (approximately 0.15ml) into the sample well, and then dispense 1-2 drops (approximately 10-40μl, do not add more than 40μl diluent) sample diluent into the sample well. For each sample or control, use a separate container, pipette and cassette.
4. Wait for colored bands to appear. Depending on the concentration of HBsAg, positive results may be observed in as short as 60 seconds. For 5ng/ml, read within 10 minutes, for 2ng/ml, read within 20 minutes. However, to confirm negative results, the complete reaction time, 30 minutes is required. Do not interpret results after 30 minutes.
Interpretation of Results: Positive: Two colored lines should be observed in the viewing window. The line in the test region (T) is the probe line, the line in the control region (C) is the control line, which is used to indicate proper performance of the device. The color intensity of the test line may be weaker or stronger than that of the control line.
Negative: The control line appears in the test window, but the test line is not visible.
Invalid: No line appears in the control region. Under no circumstances should a positive sample be identified until the control line forms in the viewing area. If the control line does not form, the test result is inconclusive and the assay should be repeated.
Limitation of Procedure: HBsAg test device is used for the detection of HBsAg in human blood. Based on a single reactive test result, a sample should not be considered HBsAg positive. Further testing, including confirmatory testing, should be performed before a specimen is considered positive for HBsAg. A non-reactive test result does not exclude the possibility of exposure to hepatitis B virus. Levels of HBsAg may be undetected both in early infection and late after infection. Specimens containing precipitate may give inconsistent test results.
The positive control in the test kit is not to be used to quantify assay sensitivity. The positive control is used to verify that the test kit components are capable of detecting a reactive specimen provided the procedure is followed as defined in the kit and the storage conditions have been strictly adhered to.
Quality Control: A procedural control is included in the test. A colored band appearing on the control region of the membrane indicates proper performance and reactive reagents. Good laboratory practices the use of external control specimens to ensure proper kit performance. Each day of testing, two level of commercial controls should be tested on the Hepatitis B Surface Antigen Test Kit. The two level of control should consist of a negative control and a positive control containing low level of HBsAg. The use of the low level positive control will assure that the test devices have not been adversely affected and are detecting HBsAg at the stated sensitivity of the test system.
V04CX - Other diagnostic agents ; Used as diagnostic agents.