Serum immunoglobulin a concentration is an independent predictor of liver fibrosis in nonalcoholic steatohepatitis before the cirrhotic stage

Background and Aims The similarity of alcoholic liver disease and nonalcoholic steatohepatitis (NASH) in terms of pathogenic mechanisms suggests that immunoglobulin A (IgA) may play an important role in the pathogenesis of NASH. We aimed to determine whether serum IgA concentrations allow a diagnosis of liver fibrosis in NASH. Methods We compared serum IgA concentrations between 108 patients with stages 0-2 NASH and 19 patients with stage 3 NASH. Results In a univariate analysis, age (P<0.0001), gender (P = 0.0039), serum albumin level (P = 0.0192), AST (P<0.0001), AST/ALT ratio (P<0.0001), platelet count (P = 0.0027), hyaluronic acid level (P<0.0001), fasting blood sugar (FBS) (P = 0.0013), IRI (P = 0.0001), prothrombin time (%) (P = 0.0287), IgA (P<0.0001), total sum of IgG, IgA, and IgM (P = 0.0049), and IgA/ (IgG + IgA + IgM) (P = 0.0105) were significantly elevated in severe-stage NASH patients compared with the early-stage NASH group. Multiple logistic regression analysis showed that in severe-stage NASH patients, only serum IgA concentrations were significantly elevated (P = 0.0225) relative to early-stage NASH patients. The area under the curve (AUC) of serum IgA concentrations was 0.758 for detecting severe-stage NASH compared with early-stage NASH. Conclusions Serum IgA concentration could be a useful independent predictor for assessing the pre-cirrhotic progression of NASH.