Histopathology and the predominantly progressive, indeterminate and predominately regressive score in hepatitis C virus patients after direct-acting antivirals therapy

Background Histological changes after direct-acting antivirals (DAAs) therapy in hepatitis C virus (HCV) patients has not been elucidated. Whether the predominantly progressive, indeterminate and predominately regressive (P-I-R) score, evaluating fibrosis activity in hepatitis B virus patients has predictive value in HCV patients has not been investigated. Aim To identify histological changes after DAAs therapy and to evaluate the predictive value of the P-I-R score in HCV patients. Methods Chronic HCV patients with paired liver biopsy specimens before and after DAAs treatment were included. Sustained virologic response (SVR) was defined as an undetectable serum HCV RNA level at 24 wk after treatment cessation. The Ishak system and P-I-R score were assessed. Inflammation improvement and fibrosis regression were defined as a ≥ 2-points decrease in the histology activity index (HAI) score and a ≥ 1-point decrease in the Ishak fibrosis score, respectively. Fibrosis progression was defined as a ≥ 1-point increase in the Ishak fibrosis score. Histologic improvement was defined as a ≥ 2-points decrease in the HAI score without worsening of the Ishak fibrosis score after DAAs therapy. The P-I-R score was also assessed. "absolutely reversing or advancing" was defined as the same directionality implied by both change in the Ishak score and posttreatment P-I-R score; and "probably reversing or advancing" was defined as only one parameter showing directionality. Results Thirty-eight chronic HCV patients with paired liver biopsy specimens before and after DAAs treatment were included. The mean age of these patients was 40.9 ± 14.6 years and there were 53% (20/38) males. Thirty-four percent (13/38) of patients were cirrhotic. Eighty-two percent (31/38) of patients achieved inflammation improvement. The median HAI score decreased significantly after SVR (pretreatment 7.0 vs posttreatment 2.0, Z = -5.146, P = 0.000). Thirty-seven percent (14/38) of patients achieved fibrosis improvement. The median Ishak score decreased significantly after SVR (pretreatment 4.0 vs posttreatment 3.0, Z = -2.354, P = 0.019). Eighty-two percent (31/38) of patients showed histological improvement. The P-I-R score was evaluated in 61% (23/38) of patients. The progressive group showed lower platelet (P = 0.024) and higher HAI scores (P = 0.070) before treatment. In patients with stable Ishak stage after treatment: Progressive injury was seen in 22% (4/18) of patients, 33% (6/18) were classified as indeterminate and regressive changes were seen in 44% (8/18) of patients who were judged as probably reversing by the Ishak and P-I-R systems. Conclusion Significant improvement of necroinflammation and partial remission of fibrosis in HCV patients occurred shortly after DAAs therapy. The P-I-R score has potential in predicting fibrosis in HCV patients.