Role of IL28B genotype in the liver stiffness increase in untreated patients with chronic hepatitis C.

The role of interleukin (IL)28B has been deepened in the treatment response to pegylated-interferon in patients affected by chronic hepatitis C (CHC). However, recently the IL28B genotypes were also related to hepatic fibrosis progression in untreated patients, using the liver biopsy. The aim of this prospective and longitudinal study was to assess the role of different IL28B genotypes in the liver stiffness progression in a cohort of untreated subjects affected by CHC. We included in this analysis all untreated patients affected by CHC and followed for at least 5years with the annual evaluation of liver stiffness using Fibroscan®. All enrolled subjects were genotyped for rs8099917 and rs12979860 IL28B polymorphisms. In the study period, 266 patients were considered. After 5years we observed the following median stiffness increases: 6.7kPa [5.1-7.8] in TT/CC, 4.9kPa [4.1-5.0] in TT/TC, 3.4kPa [3.2-3.8] in TG/TC and 1.7kPa [1.2-1.9] in GG/TT. These values were statistically significant in all groups (p<0.001). In the multivariate analysis resulted as predictive factors of liver stiffness progression the following: IL28B TT/CC genotype (OR=4.571; 95%IC=2.381-12.994; p<0.001) and IL28B GG/TT genotype (OR=0.510; 95%IC=0.289-0.712; p=0.007). In this study we evidenced that IL28B genotypes were associated with a different level of liver stiffness increase after 5years and could be used to select the patients who should be treated with priority.