HP and chronic hepatitis C virus infection: Studies have suggested that serum haptoglobin predicts liver fibrosis in hepatitis C patients where it was found that haptoglobin was one of the top candidate proteins for discriminating grade 0 from grades 1–4 liver fibrosis as well as discriminating grade 3 from grade 4 [27], while another study reported that haptoglobin serum levels were negatively correlated to scores of fibrosis (P < 0.001) and suggested that determination of haptoglobin serum level may be useful in the follow-up of patients with chronic hepatitis C [28].