Relevance of baseline viral genetic heterogeneity and host factors for treatment outcome prediction in hepatitis C virus 1b-infected patients

Utility of a one-step screening and diagnosis strategy for viremic HCV infection among people who inject drugs in Catalonia

BACKGROUND

In Catalonia (Spain), people who inject drugs (PWID) face numerous barriers to access to mainstream healthcare services for hepatitis C confirmatory diagnosis and treatment, so simplified testing strategies for viremic infection are urgently needed. Among PWID attending harm-reduction services in Catalonia, we aimed (i) to assess the utility of an in-house HCV-RNA detection assay on dried blood spots (DBS) as a one-step screening and confirmatory diagnosis strategy for hepatitis C, (ii) to estimate the prevalence of viremic HCV infection, and (iii) to identify factors associated with unawareness of viremic infection.

METHODS

A cross-sectional study of current PWID (N  = 410) was performed in four harm-reduction services. All participants underwent HCV antibody point-of-care testing and parallel DBS collection for centralized RNA testing. An epidemiological questionnaire was administered. Paired EDTA-plasma samples were additionally collected for HCV viral load testing in 300 participants.

RESULTS

HCV-RNA testing from DBS was feasible and showed 97.2% sensitivity and 100% specificity for viral loads >3000 IU/mL in real-life conditions. No significant differences in the performance when detecting viremic infections were observed between this one-step testing strategy vs. the conventional two-step algorithm involving venepuncture. Overall HCV seroprevalence was 79.8%, and prevalence of viremic infection was 58.5%. Importantly, 35.8% of viremic HCV participants were unaware of their status, and no specific socio-demographic or bio-behavioral factors independently associated with unawareness of viremic infection were identified. Among participants reporting a past or current HCV infection, 29.0% stated having received HCV antiviral treatment.

CONCLUSION

The high viremic HCV infection burden among PWID attending HRS, estimated for the first time in Catalonia, together with the low levels of awareness of viremic status and access to treatment, suggest that scaling up this one-step screening and diagnosis strategy to the network of harm-reduction services would help to achieve HCV elimination targets set by the World Health Organization.

Community-based screening of hepatitis C with a one-step RNA detection algorithm from dried-blood spots: Analysis of key populations in Barcelona, Spain

Alternative strategies are required to enhance the diagnosis of silent hepatitis C virus (HCV) infections in key populations at risk. Among them, HCV prevalence and bio-behavioural data are scarce for HIV-negative men who have sex with men (MSM) and men and trans-women sex workers. We sought to describe and assess the potential benefits of a community-based one-step HCV screening and confirmatory strategy for these populations in Barcelona. The screening strategy based on a real-time RT-PCR assay for HCV-RNA detection in dried-blood spots (DBS) was validated and implemented in addition to an antibody point-of-care test in a community centre. HCV prevalence was assessed, and bio-behavioural data were collected. The molecular assay was precise, reproducible, sensitive and specific. Four HIV-negative MSM reported being currently infected (0.75% HCV self-reported prevalence). Implementation of DBS testing was easy, and acceptability was >95%, but no silent HCV case was diagnosed (N = 580). High-risk sexual practices and drug use for sex were reported frequently. HIV prevalence was 4.7% in MSM and 10% in sex workers. Self-reported prevalence of other STIs ranged from 11.3% to 36.2%. In conclusion, HCV-RNA testing in DBS showed a good performance, but the assessed one-step strategy does not seem beneficial in this setting. Although no silent HCV infections were detected, the observed high-risk behaviours and prevalence of other STIs suggest that HCV spread should be periodically monitored among these populations in Barcelona by means of behavioural surveillance, rapid antibody testing and molecular confirmation in DBS.

Role of serum level and genetic variation of IL-28B in interferon responsiveness and advanced liver disease in chronic hepatitis C patients

Interleukin-28B (IL-28B) is suspected to be associated with response to treatment and one of the basic immunological backgrounds in liver transplant candidate (LTC). We aimed to assess whether genotypes of IL-28B can play a role in therapeutic response or advanced stages of liver disease. A total of 364 subjects were genotyped for IL-28B rs12979860 and rs8099917 SNPs using PCR-RFLP assay. Moreover, IL-28 serum level, HCV loads, and genotype were performed. A significant increase was observed in the frequencies of unfavorable rs12979860 genotypes/CT + TT in the chronic hepatitis C (CHC) and LTC groups. In the case of rs8099917, CHC group had a significantly higher frequency of unfavorable genotypes/GT + GG compared to the healthy group. IL-28B serum level was also significantly higher in healthy group compared with the CHC and LTC groups. There were no differences in the distribution of the IL-28B genotypes and haplotypes between responder and non-responder patients. Our results suggest, for the first time, that unfavorable rs12979860 genotypes can be considered one of the important immunological backgrounds in the Iranian LTC population that was confirmed with the lower IL-28 serum level compared to healthy group. Besides, there was a possible association of favorable IL-28B genotypes with lower odds of susceptibility to CHC infection but no support for a positive association between analyzed SNPs and an outcome of therapy. Moreover, non-CT haplotypes may be regarded as a genetic risk factor that can increase the chance of infection with HCV and progression toward end-stage HCV-related liver disease.

GAMMA GLUTAMYLTRANSFERASE IMPACT IN THERAPEUTIC RESPONSE OF CHRONIC HEPATITIS C: a systematic review of the literature

BACKGROUND

The standard treatment of chronic hepatitis C is the administration of pegylated interferon α2a or α2b in combination with ribavirin, but adverse effects can be observed, as well as the high cost of this therapy. Therefore, there is interest in understanding the predictors of sustained virologic response, as the gamma glutamyltransferase.

OBJECTIVE

To evaluate the serum levels of gamma glutamyltransferase as a predictor of response to treatment with pegylated interferon α and ribavirin in chronic hepatitis C.

METHODS

This is a systematic review of literature, conducted by consulting PUBMED, LILACS, MEDLINE, SCOPUS, Cochrane electronic databases, and active search of articles selected between January 2000 and April 2013.

RESULTS

A total of 4,785 titles were identified. Out of those material, following inclusion and exclusion criteria, 273 abstracts were selected, by two independent researchers. After reading those texts, the reviewers consensually included ten studies for systematization and classification, according to the criteria of the Oxford Scale. 1B studies are predominant (prospective cohort study - six studies). Rapid virologic response and early virological response were considered as estimates for the sustained virological response. The frequency of virologic response was identified in three studies and early virological response in two, with a total of 392 and 413 patients, respectively; sustained virologic response was reported in nine articles corresponding to 3,787 patients (76.5 %).

CONCLUSION

Gamma glutamyltransferase is a predictor of sustained virologic response in the treatment of chronic hepatitis C with pegylated interferon α2a or α2b associated with ribavirin.

The influence of host factors and sequence variability of the p7 region on the response to pegylated interferon/ribavirin therapy for chronic hepatitis C genotype 1b in patients from Serbia

The goal of this study was to identify host and viral factors affecting the response to pegylated interferon/ribavirin (PEG-IFN/RBV) treatment in patients with chronic hepatitis C genotype 1b. Baseline characteristics of the patients and sequences within the p7 region were analyzed in pre-treatment serum samples from 53 individuals with chronic hepatitis C genotype 1b and related to the outcome of therapy. We found a significant correlation between age and response to therapy (p < 0.001). Furthermore, the pre-treatment viral load was closely associated with the stage of liver fibrosis (p < 0.001). The presence of fewer than 4 mutations and age above 40 were significantly associated with non-response (NR) (p < 0.001). Our findings may be useful for estimating the likelihood of achieving a sustained virologic response (SVR) in patients who are chronically infected with hepatitis C virus genotype 1b.

Identifying candidates with favorable prognosis following liver transplantation for hepatocellular carcinoma: Data mining analysis

BACKGROUND AND OBJECTIVES

The optimal cutoff of each value in configuring selection criteria for pre-transplant assessment of hepatocellular carcinoma (HCC) remains uncertain.

METHODS

To build a predictive model for recurrent HCC, we performed data mining analysis on patients who underwent LT for HCC at University Health Network (n = 246). The model was externally validated using a cohort from the Scientific Registry of Transplant Recipients (SRTR) database (n = 9,769).

RESULTS

Among 246 patients, 14.6% (n = 36) experienced recurrent HCC within 2.5 years post-LT. The risk prediction model for recurrent HCC identified two subgroups with low-risk (total tumor diameter [TTD] <4 cm and serum alpha-fetoprotein [AFP] <73 ng/ml, n = 135) and with high-risk (TTD >4 cm and/or AFP >73 ng/ml, n = 111). The reproducibility of the model was validated through the SRTR database; overall patient survival rate was significantly better in low-risk group than high-risk group (P < 0.0001). Using Cox regression model, this yardstick, not Milan criteria, was revealed to efficiently predict post-transplant survival independent of underlying characteristics (P < 0.0001).

CONCLUSIONS

Grouping LT candidates with pre-LT HCC by the cutoffs of TTD 4 cm and AFP 73 ng/ml which were unearthed by data mining analysis efficiently classify patients according by the post-transplant prognosis.

Baseline factors associated with treatment response in patients infected with hepatitis C virus 1b by stratification of IL28B polymorphisms

Although the single-nucleotide polymorphism (SNP) rs12979860 in the IL28B gene is a better predictor of sustained virological response to treatment of chronic hepatitis C (CHC) than other baseline factors, some CHC patients with the favorable C allele cannot achieve a sustained virological response when treated with peginterferon plus ribavirin. The aim of this study was to examine baseline factors as predictors of rapid virological response (RVR) and complete early virological response (cEVR) to peginterferon alfa-2a plus ribavirin treatment in Chinese CHC patients with hepatitis C virus (HCV) genotype 1b, with emphasis on the difference between the rs129860 CC and CT/TT genotypes. A total of 337 treatment-naïve patients participated in this study. All patients were treated with peginterferon alfa-2a plus ribavirin at standard dosage. Serum samples from all patients were collected at baseline, week 4, and week 12 for testing of laboratory parameters, and IL28B genotypes were determined. Multivariate analysis showed that among rs12979860 CC genotype patients, glucose level and aspartate amino transferase (AST) activity were inversely associated with RVR, while abnormal platelet count and allergy inversely associated with cEVR. Among rs12979860 CT genotype patients, age below 40 years and short infection duration were associated with RVR, while age below 40 years, short infection duration, high body mass index (BMI), and no history of allergies were associated with cEVR. The baseline factors associated with the response to CHC treatment may depend on the IL28B genotype. Refinement of the baseline predictors based on IL28B genotypes may be useful for management of HCV infection.

A novel approach to identify candidate prognostic factors for hepatitis C treatment response integrating clinical and viral genetic data

The combined therapy of pegylated interferon (IFN) plus ribavirin (RBV) has been for a long time the standard treatment for patients infected with hepatitis C virus (HCV). In the case of genotype 1, only 38%–48% of patients have a positive response to the combined treatment. In previous studies, viral genetic information has been occasionally included as a predictor. Here, we consider viral genetic variation in addition to 11 clinical and 19 viral populations and evolutionary parameters to identify candidate baseline prognostic factors that could be involved in the treatment outcome. We obtained potential prognostic models for HCV subtypes la and lb in combination as well as separately. We also found that viral genetic information is relevant for the combined treatment assessment of patients, as the potential prognostic model of joint subtypes includes 9 viral-related variables out of 11. Our proposed methodology fully characterizes viral genetic information and finds a combination of positions that modulate inter-patient variability.