Hepatitis C virus (HCV) infects around 71 million people worldwide and in 2018 it is still a major health problem. Since 2011, anti-HCV therapy with availability of direct-acting antiviral drugs has revolutionized the clinical response and paved the way to eradication strategies. However, despite the high rate of sustained virological response, treatment failure may occur in a limited percentage of patients, possibly due to resistance-associated substitutions (RASs), either emergent or pre-existent even in minority viral populations. Clearly this problem may impair success of eradication strategies. With this background, several questions marks still exist around HCV treatment, including whether pan-genotypic treatments with complete effectiveness in any clinical conditions really exist outside clinical trials, the actual cost-effectiveness of genotyping testing, and utility of RAS detection in viral quasispecies by next generation sequencing approach. In this review, we describe these critical points by discussing recent literature data and our research experience.
Antiviral Agents ; Genetic Variation ; Hepacivirus ; Hepatitis C ; Hepatitis ; High-Throughput Nucleotide Sequencing ; Humans ; Treatment Failure

BACKGROUND/AIMS: Correct renal function evaluation is based on estimated glomerular filtration rates (eGFR) and complementary renal damage biomarkers, such as neutrophil gelatinase associated lipocalin (NGAL). The aim of this study was to evaluate eGFR and NGAL modifications and renal impairment during treatment with a direct acting antiviral (DAA) for chronic hepatitis C virus (HCV) infection. METHODS: A retrospective cohort study evaluated eGFR modification during treatment with DAA. Subgroup analysis on serum NGAL was conducted in those receiving sofosbuvir/ledipasvir, with complete follow-up until week 12 after the end of treatment (FU-12). RESULTS: In the 102 enrolled patients, eGFR reduction was observed (from 86.22 mL/min at baseline to 84.43 mL/min at FU-12, P=0.049). Mean NGAL increased in 18 patients (from 121.89 ng/mL at baseline to 204.13 ng/mL at FU-12, P=0.014). At FU-12, 38.8% (7/18) of patients had a plasmatic NGAL value higher than the normal range (36-203 ng/mL) compared with 11.1% (2/18) at baseline (χ2 =3,704; P=0.054). In contrast, eGFR did not change significantly over the follow-up in this subgroup. CONCLUSIONS: In conclusion, compared to a negligible eGFR decline observed in the entire cohort analyzed, a significant NGAL increase was observed after HCV treatment with DAA in a small subgroup. This could reflect tubular damage during DAA treatment rather than glomerular injury.
Antiviral Agents* ; Biomarkers ; Cohort Studies ; Follow-Up Studies ; Gelatinases ; Glomerular Filtration Rate* ; Hepacivirus ; Hepatitis ; Hepatitis C, Chronic ; Humans ; Inflammation ; Kidney ; Lipocalins* ; Neutrophils* ; Reference Values ; Retrospective Studies