TPO and infection: Hypersplenism in the cirrhosis stage, autoantibodies or immune complexes directed against platelets, direct infection of platelets and megakaryocytes by HCV, decreased level or activity of thrombopoietin (TPO), and virus-induced bone marrow suppression or direct platelet suppression are linked to the low platelet counts in HCV-infected patients before antiviral therapy [12-27].