Autoantibodies and Serum Immunoglobulins in Chronic Liver Diseases

Abstract
In a prospective consecutive study, 68 patients with various liver diseases and 67 control persons were examined for the occurrence of smooth muscle antibodies [Ab] (SMA), anti-nuclear Ab (ANA) and mitochondrial Ab (MTA) of Ig[immunoglobulin]G, IgA and IgM class. A determination of serum Ig (S-IgG, S-IgA and S-IgM) was performed. IgG-SMA in titers of > 80 occurred in 8 of 12 patients (67%) with hepatitis B antigen (HBag)-negative chronic active liver disease (CALD) and not in other diseases. Apart from 1 patient with primary biliary cirrhosis (PBC), IgG-ANA in titers of > 40 were likewise detected only in HBag-negative CALD (33%). The titers of IgG-SMA and IgG-ANA varied analogously with the biochemical liver parameters. There was a mutual exclusion between HBag and IgG-SMA/-ANA in titers of > 20, while IgM-SMA occurred in titers of 80 in 2 patients with HBag-positive CALD. The incidence and titers of IgM-SMA and -ANA were not higher than in the controls. IgA-SMA and -ANA were detected only sporadically. The MTA demonstrated were of IgG class and titers of > 40 were found only in patients with PBC (4 of 5). Some of the patients in all groups had an increased concentration of 1 or more of the serum Ig. S-IgG levels were significantly higher in CALD than in the other groups.