Clinical evaluation of antibody sensitized latex particles method for Australia antigen in serum.

There are several testing methods for the detection of Australia antigen. Among them an antibody sensitized latex particle agglutination assay (LAT) for the detection is technologically simple, sensitive, and rapid. So the detection of the antigen in the 896 specimens from hepatic diseases was carried out by LAT. IEOP. and SRID and the detection of rheumatoid factor in the LAT positives was also made by the modified method of Heller et al. The results of testing the 896 specimens from blood donors are positive in 0.8%. negative in 4.1%. false positive in 5.1%. and false negative in 0.1%. And also. it is suggested that false positive to LAT is partially due to rheumatoid factor. since 7 specimens of 9 positives for rheumatoid factor were to LAT (a rate of 67.8%). and partially due to the freshness of blood, since of 59 storage specimens at 4°C for a week there were different reactions in 21 specimens between storage specimens and fresh specimens. Two false negatives in the 61 specimens from hepatic diseases showed positive reactions in diluted specimens for LAT. The cause of false negative reactions to LAT is unclear but it may partly be due to the rheumatoid factor and other factors. These results led us to the conclusions that the LAT requires further development and that the LAT appears to be useful as a preliminary screening for detection of the antigen.