Reuters Health Information (2006-11-20): Automated assay allows early detection of HCV
Automated assay allows early detection of HCV
Last Updated: 2006-11-20 15:12:19 -0400 (Reuters Health)
NEW YORK (Reuters Health) - A new chemiluminescent magnetic-particle based immunoassay can detect hepatitis C virus (HCV) core antigen weeks earlier than detection of anti-HCV antibodies, researchers report in the November issue of the Journal of Medical Virology.
Dr. T. P. Leary and colleagues at Abbott Diagnostics, Abbott Park, Illinois note that HCV exposure in blood donors is determined serologically using anti-HCV antibodies. However, there is a window of 30 to 70 days after exposure during which antibodies are not detected.
To investigate the utility of the automated HCV core antigen detection test, which the researchers developed for use in this pre-seroconversion period, the team conducted a variety of studies.
In tests in 500 normal volunteer blood donors, the researchers established that the approach had a specificity of 99%.
The sensitivity was tested by comparison with 16 commercially available HCV seroconversion panels.
In each panel tested, HCV core antibody was detected before anti-HCV antibody. On average, the window period was reduced by more than 23 days. In panels initially negative by nucleic acid testing, the corresponding reduction was more than 34 days.
Overall, HCV core antigen was detected in more than 97% of specimens that were HCV RNA positive and antibody negative. Thus the researchers point out, the assay exhibited sensitivity "nearly equivalent to nucleic acid testing."
The investigators conclude that when used as a supplement to HCV antibody testing, the assay "provides a low cost alternative to nucleic acid testing, with near equivalent results."
J Med Virol 2006;78:1436-1440.