Thrombocytopenia associated with hepatitis C viral infection

We investigated whether chronic hepatitis C infection is associated with thrombocytopenia. Methods/Results: Thrombocytopenia (<15×104 platelets/μl) was diagnosed in 151 of 368 patients (41.0%) with chronic hepatitis C, a significantly higher proportion than that observed in patients with chronic hepatitis B (18.9%, p<0.01). Elevated titers of platelet-associated immunoglobulin G were observed in 88.1% of patients with chronic hepatitis C and in 47.1% of patients with chronic hepatitis B. Platelet-associated immunoglobulin G titers were significantly higher in patients with chronic hepatitis C (87.3±10.1 ng/107 cells) vs. those with chronic hepatitis B (30.3±6.4) or the control subjects (p<0.01). There was a significant negative correlation between platelet-associated immunoglobulin G titers and platelet counts in both chronic hepatitis C and B cases. Platelet-associated immunoglobulin G titers were significantly higher in patients with type C cirrhosis than in those with type B cirrhosis. Interestingly, HCV-RNA was detected by RT-PCR in the platelets from 11 of 14 patients with hepatitis C virus. conclusions: These data indicate that chronic infection with hepatitis C virus may produce a significant autoimmune reaction to platelets, leading to thrombocytopenia.