Abstract
The sera of 41 cases of acute hepatitis A were examined serologically to detect the changes of antibody to HAV (anti-HAV) by both RIA (HAVAB) and IAHA methods. By IAHA method anti-HAV increases rapidly of 5 weeks after the onset of the disease.
Therefore it needs the paired sera to determine the increase of anti-HAV. However, this method has two ploblems as follow: the first; the diagnosis can be made only retrospectively. The second; it's difficult to detect anti-HAV without puried HA antigen adequitely. By RIA method anti-HAV can be detect positively at the beginning of the disease. Applied the phenomenon, i.e.; IgM fraction increases at the beginning and IgG fraction increase at the convalscent stage of acute infectious illness, to hepatitis A. The ratio, M-ratio index, between IgM fraction treated by 2-ME and not treated one make more reliable diagnosis of hepatitis A through one point serum check.
These results suggest that the paired sera treated with IgM fraction give more efficient diagnosis for patients with acute hepatitis A than one point serological examination.
