Clinical evaluation of the liver cell membrane autoantibody assay.

To evaluate the clinical significance of the liver cell membrane autoantibody (LMA) assay, we studied the presence, titre and immunoglobulin classes of LMA in 162 patients with various liver diseases and 156 controls. LMA was detected predominantly in patients with HBsAg-negative chronic active hepatitis (73% of 26 patients), but was also found in lower prevalences in other liver diseases, such as primary biliary cirrhosis syndrome (43% of 28 patients). LMA-positive primary biliary cirrhosis patients could be distinguished from LMA-positive patients with other liver diseases by the virtual absence of IgG class LMA. The LMA assay adds to the panel of assays for non-organ-specific autoantibodies in that it is more specific for autoimmune liver disease and in that it increases the diagnostic yield of autoantibody assays, e.g. in HBsAg-negative chronic active hepatitis from 77 to 92%. Immunosuppressive therapy status and biochemical parameters of disease activity, such as transaminase values, did not show a statistically significant relationship with the prevalence, the titre and the immunoglobulin class of LMA. It is concluded, that LMA is a sensitive and specific diagnostic marker for autoimmune liver disease.