Hepatic steatosis in genotype 4 chronic hepatitis C patients: implication for therapy

Genotype 4 hepatitis C virus-a review of a diverse genotype

PURPOSE

Hepatitis C virus (HCV) infection remains a major health problem and one of the leading causes of chronic liver disease worldwide. The purpose of this paper was to summarize knowledge about the epidemiology of HCV genotype (GT) 4 infection, similarities and differences with other genotypes, specific problems associated with this genotype, and treatment regimens used to treat GT4-infected patients.

METHODS

We performed an accurate search for literature using the PubMed database to select high-quality reviews and original articles concerning this topic.

RESULTS

GT4 with a global prevalence of 8% takes third place, closing the global HCV podium in terms of frequency. However, there are regions where GT4 infections are dominant, such as sub-Saharan and North Africa, and the Middle East. The disease course and complications are generally similar to those of chronic hepatitis C caused by other genotypes, although the faster progression of fibrosis was demonstrated in patients with coexisting schistosomiasis. In the era of interferon-based therapy, GT4-infected patients were described as difficult to treat due to suboptimal response. A breakthrough in the treatment of HCV-infected patients, including those with GT4 infection, was the introduction of direct-acting antiviral drugs.

CONCLUSIONS

The availability of safe and effective therapy has created a real opportunity for HCV eradication in line with the goal set by the World Health Organization. An example of a country where this is happening is Egypt, where GT4 accounts for more than 90% of HCV infections. There, broad access to therapy has been effectively supported by population-based screening.

Sustained virological response and its treatment predictors in hepatitis C virus genotype 4 compared to genotypes 1, 2, and 3: a meta-analysis

BACKGROUND

Pegylated interferon and ribavirin (PEG-IFN+RBV) may be more cost-effective than direct-acting antivirals in resource-limited settings. Current literature suggests sustained virological response (SVR) in hepatitis C virus genotype 4 (HCV-4) is similar to genotype 1 (HCV-1), but worse than 2 and 3 (HCV-2/3). However, few studies have compared treatment response between these groups and these have been limited by small sample sizes with heterogeneous designs. We performed a meta-analysis of SVR predictors in HCV-4 versus HCV-1, 2, and 3 patients treated with PEG-IFN+RBV.

METHODS

In November 2013, we searched for 'genotype 4' in MEDLINE/EMBASE databases and scientific conferences. We included original articles with ≥25 treatment-naïve HCV-4 and comparisons to HCV-1, 2, and/or 3 patients treated with PEG-IFN+RBV. Random effects modelling was used with heterogeneity defined by Cochrane Q-test (p value<0.10) and I(2) statistic (>50%).

RESULTS

Five studies with 20 014 patients (899 HCV-4; 12 033 HCV-1; and 7082 HCV-2/3 patients) were included. SVR was 53% (CI 43% to 62%) for HCV-4, 44% (CI 40% to 47%) for HCV-1; and 73% (CI 58% to 84%) for HCV-2/3. SVR with EVR (early virological response) was 75% (CI 61% to 86%) in HCV-4; 64% (CI 46% to 79%) in HCV-1; and 85% (CI 71% to 93%) in HCV-2/3. SVR without EVR was 10% (CI 6% to 17%) for HCV-4; 13% (CI 12% to 15%) for HCV-1; and 23% (CI 16% to 33%) for HCV-2/3.

CONCLUSIONS

SVR rates are similar in HCV-4 (∼50%) and HCV-1 (∼40%). Lack of EVR is a good stopping rule for HCV-4 and HCV-1 since only 10% subsequently achieve SVR. In HCV-4 patients with EVR, three-quarters can expect to achieve SVR with PEG-IFN+RBV.

Interaction of IFNL3 with insulin resistance, steatosis and lipid metabolism in chronic hepatitis C virus infection

Metabolic changes are inextricably linked to chronic hepatitis C (CHC). Recently polymorphisms in the IFNL3 (IL28B) region have been shown to be strongly associated with spontaneous and treatment induced recovery from hepatitis C virus (HCV) infection. Further, circumstantial evidence suggests a link between IFNL3 single nucleotide polymorphisms and lipid metabolism, steatosis and insulin resistance in CHC. The emerging picture suggests that the responder genotypes of IFNL3 polymorphisms are associated with a higher serum lipid profile, and less frequent steatosis and insulin resistance. This review analyzes the current data regarding this interaction and its meaning for HCV pathogenesis and disease progression.

Role of viral and host factors in interferon based therapy of hepatitis C virus infection

The current standard of care (SOC) for hepatitis C virus (HCV) infection is the combination of pegylated interferon (PEG-IFN), Ribavirin and protease inhibitor for HCV genotype 1. Nevertheless, this treatment is successful only in 70-80% of the patients. In addition, the treatment is not economical and is of immense physical burden for the subject. It has been established now, that virus-host interactions play a significant role in determining treatment outcomes. Therefore identifying biological markers that may predict the treatment response and hence treatment outcome would be useful. Both IFN and Ribavirin mainly act by modulating the immune system of the patient. Therefore, the treatment response is influenced by genetic variations of the human as well as the HCV genome. The goal of this review article is to summarize the impact of recent scientific advances in this area regarding the understanding of human and HCV genetic variations and their effect on treatment outcomes. Google scholar and PubMed have been used for literature research. Among the host factors, the most prominent associations are polymorphisms within the region of the interleukin 28B (IL28B) gene, but variations in other cytokine genes have also been linked with the treatment outcome. Among the viral factors, HCV genotypes are noteworthy. Moreover, for sustained virological responses (SVR), variations in core, p7, non-structural 2 (NS2), NS3 and NS5A genes are also important. However, all considered single nucleotide polymorphisms (SNPs) of IL28B and viral genotypes are the most important predictors for interferon based therapy of HCV infection.

Comparative diagnostic study of biomarkers using FibroMax™ and pathology for prediction of liver steatosis in patients with chronic hepatitis C virus infection: an Egyptian study

BACKGROUND

Steatosis is common in patients with hepatitis C virus (HCV) infection and may be a major determinant of progression of liver injury. This study evaluated FibroMax™ for noninvasive diagnosis of steatosis in patients with chronic HCV.

METHODS

This cross-sectional study included 44 patients naïve to treatment who were referred to our hepatology clinic for assessment of fitness for antiviral therapy. Chronic HCV infection was diagnosed by viral markers. Investigations included assessment of abdominal ultrasonography, liver biopsy, calculation of body mass index, and biomarker parameters in serum using FibroMax.

RESULTS

Histopathology of liver biopsies showed steatosis in 30 of 44 (68%) patients. FibroMax results were positively correlated with viral load by quantitative polymerase chain reaction and histopathological findings. Body mass index was significantly higher in steatotic patients (P = 0.003) and was significantly associated with the results on FibroMax (P = 0.005).

CONCLUSION

FibroMax was correlated with histopathology and body mass index in patients with HCV. Abdominal ultrasonography could not be used as a single tool to diagnose steatosis with HCV. Steatosis is correlated with viral load, which suggests a direct viral effect. We recommend FibroMax assessment in a larger number of patients to assess its applicability in patients with HCV and steatosis.

Prevalence and impact of hepatic steatosis on the response to antiviral therapy in Saudi patients with genotypes 1 and 4 chronic hepatitis C

BACKGROUND

Hepatic steatosis in hepatitis C virus (HCV)-infected patients has been shown to enhance the progression of liver fibrosis and decrease the response to antiviral therapy.

AIMS

We aimed to determine the role of HCV genotype 4 (HCV-G4) in the prevalence of hepatic steatosis, its impact on antiviral therapy, and its associations and predictive factors in comparison to HCV-G1-infected patients.

METHODS

Treatment-naïve HCV patients who were started on pegylated interferon a-2b plus ribavirin therapy in two centers in Saudi Arabia were included. The severity of steatosis was assessed using the METAVIR and NAS (non-alcoholic fatty liver disease [NAFLD] activity score) scoring systems. Sustained virological response (SVR) was studied in relation to the degree of steatosis. Associations between steatosis and multiple demographic, laboratory, and virological factors were examined. HCV-G1 and HCV-G4 patients were compared.

RESULTS

A total of 116 patients (HCV-G4 85 [73.3%]; HCV-G1 31 [26.7%]) were included. The mean age was 50.4±10.7 years and 56.9% were males. In terms of steatosis grading using the NAS scoring system, 50% had steatosis grade 0, 26.7% grade 1, 14.7% grade 2, and 8.6% grade 3, while the overall staging of steatosis revealed that 43.1% had mild steatosis, 42.2% moderate, and 14.7% severe. Gamma-glutamyl transpeptidase (GGT), platelet count, body mass index (BMI), cholesterol level, presence of hyperlipidemia, liver histology stage, and grade were significantly correlated with hepatic steatosis in one or more of the statistical analyses. Twenty-two out of 55 patients (40.0%) had an SVR in the mild steatosis group, compared to 52.7% in the moderate group and 7.3% in the severe group (P=0.03). The HCV genotype did not correlate with steatosis or SVR.

CONCLUSION

Our study confirms the high prevalence of steatosis in HCV-G4 and HCV-G1 patients, but with no difference in the grade or score of steatosis between the two genotypes. The grade of steatosis correlates with GGT, platelet count, and BMI, while the NAS score of steatosis correlates with response to antiviral therapy.