SUMMARY OF THE MAJOR COMPONENTS OF THE KIT

Use this summary only as a reference and always follow the comprehensive method sheet when performing the assay. Note: the components of individual kits are not lot- interchangeable.

SUMMARY OF THE ASSAY PROCEDURE

Use this summary only as a reference and always follow the detailed method sheet when performing the assay.

INTENDED USE

Rapid HBsAg ELISA KIT (High Sensitivity) is an enzyme-linked immunosorbent assay (ELISA) for qualitative detection of HBsAg in human serum or plasma. It is intended for screening of blood donors and for diagnosing of patients related to infection with hepatitis B virus.

PERFORMANCE CHARACTERISTICS

Specificity:

When evaluated on European blood donors (n=5038), the overall diagnostic specificity of the kit was 99.78%.

During multi-center evaluation in China, this HBsAg ELISA demonstrated specificity of 99.92%.

Sensitivity:

This HBsAg ELISA was evaluated for sensitivity on 22 HBV commercial available HBV seroconversion panels, and on total 403 HBsAg positive including 146 HBsAg HBV genotyped and HBsAg subtyped plasma samples available at the Paul-Ehrlich-Institut. With respect to seroconversion sensitivity, the results for this HBsAg ELISA on the 22 HBV seroconversion panels showed a sensitivity level at least equivalent with the range of current CE marked HBsAg screening assays for which PEI holds data. 10 additional seroconversion panels were tested in-house. The seroconversion sensitivity was comparable to other CE-marked HBsAg screening test. With respect to diagnostic sensitivity this HBsAg ELISA detected all positive samples as positive, including the HBV genotypes A-F or HBsAg subtypes examined.

In conclusion, the overall score of this HBsAg ELISA for the seroconversion sensitivity was comparable with other CE marked HBsAg ELISA KIT for which PEI holds data and all 403 HBsAg positive samples were reactive giving an overall sensitivity of 100%.

Analytical sensitivity:

0.1IU/ml (NIBSC 00/588)

Analytical specificity:

No interference was observed with samples from patients with high-level of rheumatoid factor, and pregnant woman. Same day and frozen specimens have been tested to check for interferences due to collection and storage. Total of 100 samples reactive for anti-HBc, anti-HCV, and anti-HIV-1 were screened for HBsAg with HBsAg ELISA. 98 out of 100 samples were negative for HBsAg. 200 blood samples from patients were also tested with HBsAg ELISA. 191 out of 200 samples had negative screening results for HBsAg. 8 out of 9 samples with initial reactive screening results had repeat reactive test results with this HBsAg ELISA but hepatitis B virus was not confirmed in all cases.

LIMITATIONS

1. Positive results must be confirmed with another available method and interpreted in conjunction with the patient clinical information.

2. Antigens may be undetectable during the early stage of the disease. Therefore, negative results obtained  HBsAg ELISA (High Sensitivity) are only indicative that the sample does not contain a detectable level of hepatitis B virus surface antigen and any negative result should not be considered as conclusive evidence that the individual is not infected with HBV or the blood unit is not infected with HBV.

3. If, after retesting of the initially reactive samples, the assay results are negative, these samples should be considered as non-repeatable (false positive) and interpreted as negative. As with many very sensitive ELISA assays, false-positive results can occur due to the several reasons, most of which are related but not limited to inadequate washing step.

4. The most common assay mistakes are: using kits beyond the expiry date, bad washing procedures, contaminated reagents, incorrect assay procedure steps, insufficient aspiration during washing, failure to add specimens or reagents, improper operation with the laboratory equipment, timing errors, the use of highly hemolyzed specimens or specimens containing fibrin, incompletely clotted serum specimens.

5. The prevalence of the marker will affect the assay's predictive values.

6. This assay cannot be utilized to test pooled (mixed) plasma.  HBsAg ELISA (High Sensitivity) has been evaluated only with individual serum or plasma specimens.

7. HBsAg ELISA (High Sensitivity) is a qualitative assay and the results cannot be used to measure antigen concentration.

Note: The above information is for reference use only. Please refer to the product insert provided with the products before use.