Effects of iron and HFE mutations on response to therapy in chronic hepatitis C: an ironic interaction?

Role of fibrogenic and inflammatory cytokines in HCV-induced fibrosis

HCV is one of the main causative agents of liver fibrosis and hepatocellular carcinoma. Liver inflammation resulting from HCV infection triggers fibrosis. In HCV-related fibrosis, differentiated hepatic stellate cells (HSCs) known as myofibroblasts participate in the fibrogenic and inflammatory response. TGF-β1 and CTGF, released from these HSCs, have been implicated as master cytokines mediating HCV induced hepatic fibrosis. PDGF is another potent mitogen, which facilitates the progression of liver fibrosis by enhancing the proliferation and migration of HSCs. In addition to these major cytokines, the release of TNF-α, IL-6, IL-1b and IL-10 by immune cells also promotes the effect of HCV induced fibrosis. Targeting these cytokines may offer the potential for treatments to prevent or cure fibrosis.

Serum ferritin levels in chronic hepatitis C patients during antiviral therapy and prediction of treatment response

OBJECTIVE

Increased serum ferritin (SF) levels are encountered in various conditions, such as inflammatory syndromes and haemochromatosis. Interferon alpha is one of the stimulants of SF. In this study we aimed to evaluate SF changes in patients with chronic hepatitis C (CHC) during antiviral therapy, and the relationship between SF and treatment response.

METHODS

Data from a total of 97 patients who had received peginterferon (PEG-IFN) plus ribavirin combination therapy for CHC, and who had been followed up for more than 6 months after treatment, were analyzed retrospectively. Patients who had undetectable hepatitis C virus RNA at 6 months after the completion of antiviral therapy were regarded as having achieved a sustained viral response (SVR), while the remaining patients were categorized as non-SVR. Differences in SF levels during therapy between SVR patients and non-SVR patients were examined.

RESULTS

We found that patients who achieved SVR had lower baseline ferritin levels. It was observed that SF levels increased dramatically in both the SVR and non-SVR groups after starting therapy, remained high until the end of the treatment period, and returned to baseline levels after completion of treatment. However the SF rise was found to be significantly higher in patients who achieved an SVR than in those without SVR at each time-point during treatment.

CONCLUSIONS

SF levels increase during PEG-IFN-based therapy for CHC. A lower SF level before starting treatment and higher SF levels during therapy appear to be associated with a favourable treatment response. Therefore, rises in SF, especially during the early phase of treatment, could be a predictor of SVR.

Serum ferritin as a predictor of treatment outcome in patients with chronic hepatitis C

OBJECTIVES

Antiviral treatment in chronic hepatitis C (CHC) involves ribavirin, a hemolytic agent. We planned a prospective study to evaluate whether drug-induced iron perturbation is clinically relevant as it relates to therapeutic outcome.

METHODS

Iron variables were sequentially assessed in 206 CHC patients undergoing antiviral therapy and were correlated with pretreatment iron status and histology, hemolysis, and therapeutic outcome.

RESULTS

At week 1 of therapy, serum iron (SI), transferrin saturation (TS), and serum ferritin (SF) increased markedly in all patients. All iron parameters correlated with hemolysis up to week 4; this correlation was lost for SF at later time points. SF rise during treatment was inversely related to baseline SF and iron deposits in hepatic mesenchymal/Kupffer cells. Both baseline SF and mesenchymal iron significantly correlated with fibrosis at multivariate analysis (P=0.015 and 0.008, respectively). Interestingly, baseline SF, despite good specificity (89%), had low sensitivity in predicting siderosis (25%). During therapy, SI, TS, and hemolysis parameters did not correlate with sustained virological response (SVR), whereas SF rise became an independent predictor of therapeutic response: a 2.5-fold increase of SF at week 12 associated with higher likelihood of SVR (odds ratio 1.91, P=0.032). Accordingly, lack of mesenchymal iron deposits at the baseline biopsy correlated with SVR (odds ratio 3.02, P=0.043).

CONCLUSIONS

In CHC, SF is a useful marker for assessing disease duration and progression before starting treatment and for predicting therapeutic response while on therapy. SF rise during antiviral therapy is largely independent of hemolysis and likely indicates activation of macrophages in response to antivirals.