Abstract
The prevalence and characteristics of patients with hepatitis C virus mixed genotype 1 and 2 infection (HCV-1/2) remains unclear. For each HCV-1/2 patient with histological data available, two age- and sex-matched HCV-1 and HCV-2 infected patients were selected for comparison, respectively. Of the 2776 patients, 261 (9.4%) patients were identified as having mixed HCV-1/2 infection. The histological severity did not differ among HCV-1/2 patients and controls. The proportion of patients with the interleukin-28B (IL-28B) rs8099917 TT genotype did not differ between patients with mixed-1/2 and HCV-1 infection (82.6% vs. 86.5%, p = 0.38). However, HCV-2 infected patients had a significantly higher proportion of the rs8099917 TT genotype compared to patients with mixed HCV-1/2 infections (91.6% vs. 82.6%, p = 0.03). The HCV RNA levels were similar in patients with HCV-1/2 and HCV-1 infections (5.5 ± 0.8 log IU/mL vs. 5.5 ± 0.9 log IU/L, p = 0.73), which were both significantly higher than that of HCV-2 infection (5.1 ± 0.9 log IU/mL, both p < 0.001). Linear regression analysis revealed that the factors of HCV-1/2 infection [β: 0.204; 95% confidence interval (CI): 0.183-0.598, p < 0.001], body weight (β: 0.150; CI: 0.003-0.021, p = 0.008), and age (β: -0.139; CI: -0.020 to -0.002, p = 0.01) were independently correlated with HCV RNA levels in patients with HCV-2 and mixed HCV-1/2 infection. We concluded that the host genetic and viral presentations of patients with mixed HCV-1/2 infection were more similar to those of patients with HCV-1 infection than patients with HCV-2 infection.