Effect of direct-acting antivirals on platelet-associated immunoglobulin G and thrombocytopenia in hepatitis C virus-related chronic liver disease

Background & Aims Hepatitis C virus (HCV) infection has been known to cause various extrahepatic autoimmune disorders. The prevalence of platelet-associated immunoglobulin G (PA-IgG) has been high in patients with HCV infection. Because thrombocytopenia in HCV-related liver diseases is a notable problem, we performed prospective study on the effect of direct-acting antivirals (DAAs) treatment on PA-IgG and platelet count. Methods A total of 215 patients with HCV-related liver disease were enrolled in this study. The patients who discontinued DAAs or did not undergo adequate laboratory examinations and who did not achieve sustained virologic response were excluded and finally a total of 187 patients were investigated. Results A total of 171 patients (91.4%) were PA-IgG positive (>46 ng/10(7) cells) before starting DAAs (baseline). The PA-IgG level elevation was significantly correlated with higher liver inflammation and fibrosis markers (P < 0.05) and lower platelet count (P = 0.000019). The platelet count of the patients with low PA-IgG titer tended to be higher at baseline, end of treatment (EOT), and at 12 and 24 weeks after EOT. The platelet count increased at EOT (P < 0.05) and 24 weeks after EOT (P < 0.01). The PA-IgG levels were significantly decreased at EOT, 12 and 24 weeks after EOT (P < 0.01). Multiple regression analysis found that only platelet count at baseline was closely associated with negative conversion of PA-IgG at 24 weeks after EOT (P = 0.004). Conclusions Eradication of HCV by DAAs treatment successfully decreased PA-IgG level and increased platelet count.