Hepatitis C genotypes and subtypes in Saudi Arabia

Efficacy and Safety of Simeprevir or Daclatasvir in Combination With Sofosbuvir for the Treatment of Hepatitis C Genotype 4 Infection

INTRODUCTION

The combination of sofosbuvir (SOF) with simeprevir (SMV) or daclatasvir (DCV) is very effective in treating hepatitis C virus (HCV) infection, particularly genotype (GT) 1. However, the data on GT4 are very limited. We aimed to determine the efficacy and safety of SOF in combination with either SMV or DCV in GT4-infected patients.

PATIENTS AND METHODS

In this real life, prospective, observational study, HCV (GT4) patients (n=96) were evaluated in 2 groups on the basis of the 12-week treatment regimen they received. Group 1 (n=56) patients were treated with SOF and SMV±ribavirin (RBV), whereas group 2 patients were treated with SOF and DCV±RBV (n=40). The primary efficacy endpoint was sustained virologic response 12, whereas the primary safety endpoint was drug discontinuation or occurrence of grade 3/4 adverse events.

RESULTS

The mean age was 49±14.6 years (59.4% men). Cirrhosis was present in 53.6% and 35.0% of groups 1 and 2, respectively, whereas 27 patients (48.2%) in group 1 and 21 patients (52.5%) in group 2 had failed prior interferon-based treatment. The median pretreatment HCV-RNA log10 was 6.1 (3.6 to 7.0) and 6.0 (3.6 to 7.2) IU/mL in groups 1 and 2, respectively. RBV was given to 17 patients (30.4%) in group 1 and 2 patients (5%) in group 2. All patients achieved sustained virologic response 12 (100%). Adverse events occurred in 32% of patients (grade 1 and 2), but none discontinued treatment. One patient died in the SMV group (not related to treatment).

CONCLUSIONS

SMV/SOF or DCV/SOF combinations are safe and highly effective in HCV-GT4 treatment. Cirrhosis and failure of prior interferon-based treatment did not influence treatment response.

Determinants of Infection Outcome in HCV-Genotype 4

Hepatitis C virus (HCV) infection represents a worldwide health problem and has been for long an attractive point of research due to diversity among different genotypes regarding unique geographical distribution and diverse treatment outcome. HCV is considered a major cause of chronic liver disease and cirrhosis, which leads to liver failure and hepatocellular carcinoma requiring liver transplantation. Of the HCV genotypes identified, HCV genotype 4 (HCV-4) is the least studied. HCV-4 is responsible for ∼10% of HCV infections and is common in the Middle East and Africa; recently it is increasingly prevalent in European Countries. HCV-4 is a continuing epidemic in Egypt, having the highest prevalence of HCV worldwide. "Know your epidemic, know your response" concept necessitates better understanding of HCV-4 characteristics to control disease dissemination and progression, which compromises the life quality of chronic HCV-infected patients. In this review, we discuss the epidemiology, natural history, and treatment options for patients with HCV-4 infection.

Prevalence of hepatitis C virus genotypes and subtypes in Lebanese population and major high risk groups

BACKGROUND AND STUDY AIMS

The prevalence of hepatitis C in Lebanon is low. It is estimated at 0.2% of the total population. The aim of our study is to evaluate the exact prevalence of each genotype on a large scale population and in each potential source of infection.

PATIENTS AND METHODS

We reviewed all the data in the Ministry of Public Health related to patients who have submitted their file for treatment during a period of 9years ranging from January 2005 till December 2013.

RESULTS

The genotype distribution in 1031 Lebanese patients was as following: Genotype 1 was the most predominant representing 47% followed by genotype 4 representing 34% then genotype 3 representing14%. Concerning sex distribution and routes of infection, there was a male predominance in intravenous drug users (IVDU), whereas approximately equal distribution was noted in haemodialysis and transfusion groups. A female predominance was noted in the "unknown" mode of infection. Concerning age distribution and routes of infection, a mean age of 27 was noted in the IVDU group, whereas mean age of 60 in the transfusion group and 50 in the haemodialysis group. In patients who acquired the infection post transfusion or during haemodialysis, genotype 1 was the most predominant, whereas in IVDU, genotype 3 was the most predominant. Concerning sub-genotyping: subtype 1b was the most predominant (84%) in genotype 1. in genotype 2 subtype b with 75%, all genotype 3 were subtype a, in genotype 4 subtype a represents 50% of genotype followed by subtype e in 30%.

CONCLUSION

Our data concerning Lebanese population demonstrate that genotype 1 is the most prevalent genotype followed by genotype 4. In IVU, we noted genotype-3 and -1 being the most prevalent in relation to clustering in this high risk group. This distribution differs from most surrounding countries and all other Arab countries.

Partial sequencing analysis of the NS5B region confirmed the predominance of hepatitis C virus genotype 1 infection in Jeddah, Saudi Arabia

Chronic hepatitis C virus (HCV) infection and its progression are major health problems that many countries including Saudi Arabia are facing. Determination of HCV genotypes and subgenotypes is critical for epidemiological and clinical analysis and aids in the determination of the ideal treatment strategy that needs to be followed and the expected therapy response. Although HCV infection has been identified as the second most predominant type of hepatitis in Saudi Arabia, little is known about the molecular epidemiology and genetic variability of HCV circulating in the Jeddah province of Saudi Arabia. The aim of this study was to determine the dominance of various HCV genotypes and subgenotypes circulating in Jeddah using partial sequencing of the NS5B region. To the best of our knowledge, this is the first study of its kind in Saudi Arabia. To characterize HCV genotypes and subgenotypes, serum samples from 56 patients with chronic HCV infection were collected and subjected to partial NS5B gene amplification and sequence analysis. Phylogenetic analysis of the NS5B partial sequences revealed that HCV/1 was the predominant genotype (73%), followed by HCV/4 (24.49%) and HCV/3 (2.04%). Moreover, pairwise analysis also confirmed these results based on the average specific nucleotide distance identity: ±0.112, ±0.112, and ±0.179 for HCV/1, HCV/4, and HCV/3, respectively, without any interference between genotypes. Notably, the phylogenetic tree of the HCV/1 subgenotypes revealed that all the isolates (100%) from the present study belonged to the HCV/1a subgenotype. Our findings also revealed similarities in the nucleotide sequences between HCV circulating in Saudi Arabia and those circulating in countries such as Morocco, Egypt, Canada, India, Pakistan, and France. These results indicated that determination of HCV genotypes and subgenotypes based on partial sequence analysis of the NS5B region is accurate and reliable for HCV subtype determination.

Tracing the epidemic history of hepatitis C virus genotypes in Saudi Arabia

HCV genotype 4 is highly prevalent in many Middle Eastern countries, yet little is known about the genotype's epidemic history at the subtype-level in this region. To address the dearth of data from Saudi Arabia (SA) we genotyped 230 HCV isolates in the core/E- and NS5B-region and analyzed using Bayesian phylogenetic approaches. HCV genotype 4 (HCV/4) was positive in 61.7% (142/230) of isolates belonging to 7 different subtypes with the predominance of 4d (73/142; 51.4%) followed by 4a (51/142; 35.9%). Phylogenetic analysis also revealed a distinct epidemiological cluster of HCV/4d for Saudi Arabia. HCV/1 appeared as the second most prevalent genotype positive in 31.3% (72/230) of isolates with the predominance of 1b (53/72; 73.6%) followed by 1a (16/72; 22.2%), and 1g (3/72; 4.1%). A small proportion of isolates belonged to HCV/3a (12/230; 5.2%), and HCV/2a (4/230; 1.7%). We estimate that the genotype 4 common ancestor existed around 1935 (1850-1985). Genotype 4 originated plausibly in Central Africa and multiple subtypes disseminated across African borders since ~1970, including subtype 4d which dominates current HCV infections in Saudi Arabia. The Bayesian skyline plot (BSP) analysis showed that genotype 4d entered the Saudi population in 1900. The effective number of HCV infections grew gradually until the second half of the 1950s and more rapidly until the early-80s through the use of imported blood units and blood products. Subsequently, the rate of HCV infection in the Saudi Arabian population was stabilized through effective screening of blood and infection control measures.

Comparison of Three Different Hepatitis C Virus Genotyping Methods: 5'NCR PCR-RFLP, Core Type-Specific PCR, and NS5b Sequencing in a Tertiary Care Hospital in South India

BACKGROUND

Based on genetic heterogeneity, hepatitis C virus (HCV) is classified into seven major genotypes and 64 subtypes. In spite of the sequence heterogeneity, all genotypes share an identical complement of colinear genes within the large open reading frame. The genetic interrelationships between these genes are consistent among genotypes. Due to this property, complete sequencing of the HCV genome is not required. HCV genotypes along with subtypes are critical for planning antiviral therapy. Certain genotypes are also associated with higher progression to liver cirrhosis.

METHODS

In this study, 100 blood samples were collected from individuals who came for routine HCV genotype identification. These samples were used for the comparison of two different genotyping methods (5'NCR PCR-RFLP and HCV core type-specific PCR) with NS5b sequencing.

RESULTS

Of the 100 samples genotyped using 5'NCR PCR-RFLP and HCV core type-specific PCR, 90% (κ = 0.913, P < 0.00) and 96% (κ = 0.794, P < 0.00) correlated with NS5b sequencing, respectively. Sixty percent and 75% of discordant samples by 5'NCR PCR-RFLP and HCV core type-specific PCR, respectively, belonged to genotype 6. All the HCV genotype 1 subtypes were classified accurately by both the methods.

CONCLUSION

This study shows that the 5'NCR-based PCR-RFLP and the HCV core type-specific PCR-based assays correctly identified HCV genotypes except genotype 6 from this region. Direct sequencing of the HCV core region was able to identify all the genotype 6 from this region and serves as an alternative to NS5b sequencing.

The Distribution of Hepatitis C Virus Genotypes in Middle Eastern Countries: A Systematic Review and Meta-Analysis

CONTEXT

The hepatitis C virus (HCV) is classified into seven genotypes and more than 100 subtypes. The treatment regimen, duration and efficacy of HCV therapy may vary according to the HCV genotype. Therefore, the HCV genotype should be determined prior to antiviral therapy. The objective of the current study was to review systematically all studies reporting the distribution of HCV genotypes in the countries that make up the Middle East.

EVIDENCE ACQUISITION

Articles were identified by searching electronic databases, including Scopus, PubMed and Google scholar, with timeline limits (articles published between 1995 and 2016). We carried out a systematic search regarding the distribution of HCV genotypes in Middle Eastern countries.

RESULTS

A total of 579 studies were identified by the electronic search. Of these, a total of 187 were identified as eligible papers including 60,319 patients who were meta-analyzed for pooled distribution of HCV genotypes. In Turkey, Israel, Cyprus, and Iran, genotype 1 was the most prevalent HCV genotype with rates of 82% (95% CI, 82%-83%), 68% (95% CI, 67%-69%), 68% (95% CI, 59%-77%), and 55% (95% CI, 54%-55%), respectively. In Egypt, Iraq, Saudi Arabia, and Syria, HCV genotype 4 was the most common genotype with rates of 86% (95% CI, 85%-88%), 60% (95% CI, 56%-64%), 56% (95% CI, 54%-55%), and 57% (95% CI, 54%-61%), respectively. On the basis of adjusted data, HCV genotype 4 was the most prevalent genotype in the Middle East region, with a rate of 74.7% (95% CI, 73.4%-76%), followed by genotype 1 at 15.1% (95% CI, 14.1%-16%).

CONCLUSIONS

Our results showed that HCV genotype 4 is the most prevalent genotype in the Middle East region. However, HCV genotype 1 is the most prevalent among non-Arab countries in the region including Turkey, Iran, Cyprus, and Israel.

Distribution of Hepatitis C Virus Genotypes in Bahrain

BACKGROUND

Approximately 170 million people are infected with Hepatitis C virus (HCV) worldwide, making it one of the world's major infectious diseases. There are no published population based studies about the prevalence of HCV genotypes in Bahrain.

OBJECTIVES

Therefore, the aim of the present study was to investigate the prevalence and distribution of HCV genotypes and subtypes among a large sample of patients with chronic HCV infection in Bahrain.

PATIENTS AND METHODS

Serum samples were collected from 202 HCV positive patients; of them 128 had a viral load (> 500 IU/mL) suitable for the type-specific genotyping assay. Gender-wise and age-wise differences in the distribution of HCV genotypes were determined by Chi Square and Fisher's Exact tests.

RESULTS

The predominant genotype among Bahraini patients was type 1 (36.71%), followed by genotypes 3 and 4 (15.6% each) and the lowest frequency was found for genotype 2 (3.9%). Among genotype 1, subtype 1b had the highest frequency (21.09%), followed by subtype 1a (14.06%). Among genotype 3, subtype 3a had the highest frequency (11.72%), while among genotype 4, most of subtypes were undetermined. The frequency of all different HCV genotypes was higher in male patients compared to female patients. Genotype 1 was most common in the age group of 51 - 60 years (38.3%), genotype 2 in 21 - 30 years (60%) and genotype 3 in 51 - 60 years (30%), while genotype 4 was most frequent among the age group > 61 (40%).

CONCLUSIONS

The most common HCV genotype in Bahrain was subtype 1b followed by 1a and 3a. Further studies involving sources of transmission in Bahrain are required to enhance control measures for HCV infection.

Review article: the epidemiology and therapy of chronic hepatitis C genotypes 4, 5 and 6

BACKGROUND

The global burden of hepatitis C (HCV) infection is mostly found in Africa, the Middle East and Asia, where HCV genotypes 4, 5 and 6 are common. The literature on these genotypes is sparse and this synopsis will review characteristics of patients infected with these genotypes.

AIM

To review characteristics of patients infected with HCV genotypes 4, 5 and 6.

METHODS

PubMed search for 'hepatitis C' AND 'genotype 4', 'hepatitis C' AND 'genotype 5', and 'hepatitis C' AND 'genotype 6' was conducted and relevant articles were reviewed.

RESULTS

Intravenous drug use is generally responsible for HCV genotype 4 infection in developed countries, but unsafe medical practices cause most cases of HCV genotypes 4, 5 and 6 in endemic countries. The sustained virological response (SVR) rate for patients with HCV genotype 4 who receive pegylated interferon and ribavirin for 48 weeks ranges from 40% to 70% in various small studies. The SVR rate is in the 60-70% range for HCV genotype 5 and 70-80% range for HCV genotype 6 following 48 weeks with pegylated interferon and ribavirin. Preliminary data suggest that a shorter course of 24 weeks of pegylated interferon and ribavirin may be acceptable for HCV genotype 6, with an SVR rate of approximately 70%.

CONCLUSIONS

The current standard-of-care therapy for HCV genotypes 4, 5 and 6 is pegylated interferon and ribavirin for 48 weeks. A shorter course with 24 weeks of therapy may be considered for patients with genotype 6. Newer and much more effective therapies may be forthcoming in the next few years.

Epidemiology and natural history of HCV infection

Worldwide, an estimated 130-170 million people have HCV infection. HCV prevalence is highest in Egypt at >10% of the general population and China has the most people with HCV (29.8 million). Differences in past HCV incidence and current HCV prevalence, together with the generally protracted nature of HCV disease progression, has led to considerable diversity in the burden of advanced liver disease in different countries. Countries with a high incidence of HCV or peak incidence in the recent past will have further escalations in HCV-related cirrhosis and hepatocellular carcinoma (HCC) over the next two decades. Acute HCV infection is difficult to detect because of the generally asymptomatic nature of the disease and the marginalization of at-risk populations. Around 25% of patients with acute HCV infection undergo spontaneous clearance, with increased rates among those with favourable IL28B genotypes, acute symptoms and in women. The remaining 75% of patients progress to chronic HCV infection and are subsequently at risk of progression to hepatic fibrosis, cirrhosis and HCC. Chronic hepatitis C generally progresses slowly in the initial two decades, but can be accelerated during this time as a result of advancing age and co-factors such as heavy alcohol intake and HIV co-infection.

[Hepatitis C virus genotype 5 in Mexico: a case report with successful treatment and a literature review]

Hepatitis C virus (HCV) genotype 5 is extremely rare and there is very little reported on its management in the medical literature. We present herein the case of a patient with HCV genotype 5 that presumably acquired the disease through a blood transfusion during infancy. Sustained virologic response was achieved after 24 weeks of treatment. According to the available information on HCV genotype 5 treatment, it has a similar response to that of HCV genotype 1. Our patient presented with various favorable outcome factors. There is much less reported on the treatment of HCV genotype 5 than there is regarding HCV genotypes 1, 2, 3, and 4. This is mainly due to the low prevalence of genotype 5 in the Mexican environment.

Cytokines genes polymorphisms in chronic hepatitis C: impact on susceptibility to infection and response to therapy

BACKGROUND

Cytokines play a key role in the regulation of immune responses. In hepatitis C virus infection, the production of abnormal cytokine levels appears to contribute in the progression of the disease, viral persistence, and affects response to therapy. Cytokine genes polymorphisms located within the coding/regulatory regions have been shown to affect the overall expression and secretion of cytokines. The aim of the study was to evaluate the association of of IL28B rs12979860, TGF-β1-509, TNF-α 308, and IL-10-1082 polymorphisms with the susceptibility to hepatitis C virus genotype 4 infection and response to pegylated interferon-α and ribavirin therapy.

METHODS

IL28B, TGF-β1 and TNF-α genes polymorphisms were genotyped using polymerase chain reaction (PCR)-based restriction fragment length polymorphism assay while IL-10 gene polymorphism was detected by sequence specific primer-PCR in 220 healthy individuals and 440 hepatitis C infected patients (220 sustained virological response and 220 non-responder to combination therapy).

RESULTS

IL28 B CT and TT, TGF-β1 CT and TT and TNF-α AG and AA genotypes were significantly associated with susceptibility to hepatitis C infection and response to therapy. While no association was found between IL-10 gene polymorphism and susceptibility to HCV infection and response to treatment.

CONCLUSIONS

These results suggested that inheritance of IL28B CT and TT, TGF-β1 CT and TT and TNF-α AG and AA genotypes which appear to affect the cytokine production may be associated with susceptibility to HCV infection and resistance to combined antiviral therapy.

HCV genotypes among 1013 Saudi nationals: a multicenter study

BACKGROUND AND OBJECTIVES

Hepatitis C virus (HCV) genotype (G) knowledge is essential for determining type, duration and rate of response to antiviral therapy, possible route of HCV transmission, and future vaccine development. Our aim was to study HCV genotypes and to provide precise data on genotype distribution in both genders and different age groups amongst Saudi patients.

DESIGN AND SETTING

Genotype data from molecular laboratories at four different tertiary care hospitals in Riyadh from January 2006 until December 2010 were collected and analyzed.

PATIENTS AND METHODS

Consecutive data on genotype, sex and age was collected from 1013 Saudi patients. Genotyping was done by selective hybridization of amplicons to HCV genotype-specific oligonucleotides.

RESULTS

We found G1 in 262 patients (25.9%), G2 in 44 (4.4 %), G3 in 29 (2.9 %), G4 in 608 (60%), and 3 patients (0.3%) each of G5 and G6. In addition, 64 (6.3%) patients had mixed genotypes, mostly G4 and G1. On subtyping in 191 G1 patients, 67 (35.1%) were G1a, and 124 (64.9 %) G1b. Age distribution showed that 18 (1.7%) were 0-20 years, 173 (17.1 %) 21-40 years, 521 (51.4%) 41-60 years and 301(29.7%) > 60 years. There was no significant difference in frequency of G1, G3 and G4 among the two genders.

CONCLUSION

G1 and G4 are the predominant genotypes in Saudi patients infected with HCV (85.9%), with a similar distribution among the two sexes and no significant changes in genotype distribution over the past decade.

Prevailing genotypes of hepatitis C virus in Saudi Arabia: a systematic analysis of evidence

BACKGROUND AND OBJECTIVES

Although hepatitis C virus (HCV) genotype 4 has been reported to be prevalent in some countries of the Middle East, the genotype distribution in some geographical areas is not conclusive. We aimed to perform a meta-analysis on available literature on this issue in an attempt to identify or confirm the prevailing HCV genotypes in Saudi Arabia.

METHODS

We searched for reports describing genotypes in Saudi Arabia. A meta-analysis was performed on the samples in 18 studies, published between 1995 and 2011, in which HCV genotypes were identified.

RESULTS

A total of 2277 specimens from 18 studies showed that 617, 82, 119 and 1198 subjects were HCV-positive for genotypes 1, 2, 3 and 4, respectively. The meta-analyses showed that there is a great deal of heterogeneity in estimated prevalence among the studies. The highest prevalence was found in genotype HCV-4, followed by HCV-1, HCV-3, and HCV-2.

CONCLUSION

Our meta-analysei emphasizes that HCV genotype 4 is the most prevalent, followed by genotype 1. Further studies on genotype determination and subtype distribution are warranted.

The future for the treatment of genotype 4 chronic hepatitis C

Hepatitis C virus genotype 4 (HCV-4) is the most common type of hepatitis C virus (HCV) in the Middle East and Africa, in particular Egypt. Since the development of new protease inhibitors, the response of HCV-4 to the standard regimen of treatment (pegylated interferon/ribavirin) lags behind other genotypes and has become the most resistant type to treat. The development of therapeutic strategies for all patients with HCV-4 whether they are naïve, have experienced a virological breakthrough, are relapsers or non-responders is still a considerable challenge. New types of interferon (Consensus Interferon, Y-shaped, Albinterferon...) and new direct action antiviral drugs (Nitazoxanide, Vit.D, other) may improve the treatment of patients with HCV-4. The IL28B CC polymorphism may be associated with sustained virological response.

A systematic review of hepatitis C virus epidemiology in Asia, Australia and Egypt

BACKGROUND

The hepatitis C pandemic has been systematically studied and characterized in North America and Europe, but this important public health problem has not received equivalent attention in other regions.

AIM

The objective of this systematic review was to characterize hepatitis C virus (HCV) epidemiology in selected countries of Asia, Australia and Egypt, i.e. in a geographical area inhabited by over 40% of the global population.

METHODOLOGY

Data references were identified through indexed journals and non-indexed sources. In this work, 7770 articles were reviewed and 690 were selected based on their relevance.

RESULTS

We estimated that 49.3-64.0 million adults in Asia, Australia and Egypt are anti-HCV positive. China alone has more HCV infections than all of Europe or the Americas. While most countries had prevalence rates from 1 to 2% we documented several with relatively high prevalence rates, including Egypt (15%), Pakistan (4.7%) and Taiwan (4.4%). Nosocomial infection, blood transfusion (before screening) and injection drug use were identified as common risk factors in the region. Genotype 1 was common in Australia, China, Taiwan and other countries in North Asia, while genotype 6 was found in Vietnam and other Southeast Asian countries. In India and Pakistan genotype 3 was predominant, while genotype 4 was found in Middle Eastern countries such as Egypt, Saudi Arabia and Syria.

CONCLUSION

We recommend implementation of surveillance systems to guide effective public health policy that may lead to the eventual curtailment of the spread of this pandemic infection.

Treatment of genotype 4 hepatitis C recurring after liver transplantation using a combination of pegylated interferon alfa-2a and ribavirin

BACKGROUND

Hepatitis C virus (HCV) recurrence after liver transplantation (LT) is universal and tends to be more aggressive. Data on post-transplant HCV genotype 4 treatment is scarce. The aim of this study is to assess the safety and efficacy of pegylated interferon alpha-2a (PEG-IFN) in combination with ribavirin in the treatment of recurrent HCV genotype 4 after LT.

METHODS

Twenty-five patients infected with HCV genotype 4 were treated with PEG-IFN alpha-2a at a dose of 180 μg/week in addition to 800 mg/day of ribavirin (the dose was adjusted within the tolerated range of 400-1,200 mg). Pretreatment liver biopsies were obtained from all patients. Biochemical and virological markers were assessed before, during, and after treatment.

RESULTS

Twenty-two patients (88%) achieved an early virological response (EVR) (12 patients tested negative for HCV-RNA). Fifteen (60%) and 14 patients (56%) achieved an end of treatment virological response (ETVR) and a sustained virological response (SVR), respectively. Five patients had advanced pretreatment liver fibrosis. Pretreatment ALT was elevated in 24 patients (96%). The most common adverse effects were flu-like symptoms and cytopenia. Eighteen patients (72%) required erythropoietin alpha and/or granulocyte-colony stimulating factor as a supportive measure. One patient developed severe rejection complicated by sepsis, renal failure, and death. Other adverse effects included depression, mild rejection, impotence, itching, and vitiligo.

CONCLUSIONS

Post-transplant treatment with pegylated interferon alpha-2a and ribavirin achieved SVR in 56% of liver transplant recipients with chronic HCV genotype 4 infection. The combination was relatively safe and exhibited a low rate of treatment withdrawal.

Hepatitis C virus genotype 4 therapy: progress and challenges

The hepatitis C virus genotype 4 (HCV-4) is prevalent in Egypt, the Middle East and Africa. Recently, the epidemiology of HCV-4 has changed and this genotype has begun to cross borders and spread to several regions in Europe through immigration and injection drug use. HCV-4 has been considered a difficult-to-treat genotype based on the low sustained virological response (SVR) rates obtained with conventional interferon (IFN)-based regimens. Pegylated interferons (PEG-IFN) plus ribavirin therapy for chronic HCV-4 has been associated with increased SVR rates of more than 60%. Shorter treatment of chronic HCV-4 patients with rapid and early virological responses has been associated with high SVR rates, better compliance, fewer adverse events and lower costs. Despite this progress, the treatment of HCV-4 non-responders, injection drug users, patients coinfected with human immunodeficiency virus, thalassaemic patients, patients on haemodialysis and patients with HCV-4 recurrence after liver transplantation still represents a significant therapeutic challenge. Treatment of HCV-4 has markedly improved, with higher sustained response rates and the possibility of shorter regimens. Despite the recent progress in the treatment of HCV-4, more research is required to optimize current therapy and include genotype 4 patients in clinical trials on emerging therapies such as specifically targeted antiviral therapy for HCV with protease and/or polymerase inhibitors.

An overview about hepatitis C: a devastating virus

Hepatitis C (HCV) is the disease that has affected around 200 million people globally. HCV is a life threatening human pathogen, not only because of its high prevalence and worldwide burden but also because of the potentially serious complications of persistent HCV infection. Chronicity of the disease leads to cirrhosis, hepatocellular carcinoma and end-stage liver disease. HCV positive hepatocytes vary between less than 5% and up to 100%, indicating the high rate of replication of viral RNA. HCV has a very high mutational rate that enables it to escape the immune system. Viral diversity has two levels; the genotypes and Quasiaspecies. Major HCV genotypes constitute genotype 1, 2, 3, 4, 5 and 6 while more than 50 subtypes are known. All HCV genotypes have their particular patterns of geographical distribution and a slight drift in viral population has been observed in some parts of the globe.

Special issues related to hematopoietic SCT in the Eastern Mediterranean region and the first regional activity report

Although several centers are now performing allogeneic hematopoietic SCT (HSCT) in the Eastern Mediterranean (EM) region, the availability is still limited. Special issues including compatible donor availability and potential for alternative donor programs are discussed. In comparison to Europe and North America, differences in patterns of diseases and pre-HSCT general status, particularly for patients with BM failure, are described. Other differences including high sero-positivity for CMV, hepatitis B and C infection, and specific observations about GVHD and its relation to genetically homogeneous communities are also discussed. We report that a total of 17 HSCT programs (performing five or more HSCTs annually) exist in 9 countries of the EM region. Only six programs are currently reporting to European Group for Blood and Marrow Transplantation or Center for International Blood and Marrow Transplantation Research. A total of 7617 HSCTs have been performed by these programs including 5701 allogeneic HSCTs. The area has low-HSCT team density (1.56 teams per 10 million inhabitants vs 14.43 in Europe) and very low-HSCT team distribution (0.27 teams per 10 000 sq km area vs <1-6 teams in Europe). Gross national income per capita had no clear association with low-HSCT activity. Much improvement in infrastructure and formation of an EM regional HSCT registry are needed.

Predictors of sustained virological response to a 48-week course of pegylated interferon alfa-2a and ribavirin in patients infected with hepatitis C virus genotype 4

BACKGROUND AND OBJECTIVES

Knowledge of the predictors of sustained viral response (SVR) to pegylated interferon (PEG-INF) alfa-2a and ribavirin (RBV) therapy in patients with hepatitis C genotype-4 (HCV-4) is crucial for selecting patients who would benefit most from therapy. We assessed the predictors of SVR to this combination therapy in Saudi patients with chronic HCV-4 infection.

PATIENTS AND METHODS

This retrospective study included 148 patients with HCV-4 infection who underwent clinical, biochemical and virological assessments before treatment and at 12, 24, 48 and 72 weeks post-treatment.

RESULTS

Of the 148 patients, 90 (60.8%) were males. Mean (SD) for age was 48.5 (12.7) years and BMI was 27.9 (7.5) kg/m(2). Seventy-nine of 148 (60.1%) patients were treatment naïve and 110 (74.3%) underwent pre-treatment liver biopsy. Eighteen (12.2%) patients did not complete therapy because of side effects or they were lost to follow up. Early virological response was achieved in 84 of 91 (92.3%) patients. In the 130 (87.8%) patients who completed therapy, 34 (26.2%) were non-responders and 96 (63.8%) achieved end-of-treatment virological response (ETVR). SVR and virological relapse (24 weeks after ETVR) occurred in 66/130 (50.7%) and 30/130 (31.2%) patients, respectively. Compared to relapsers, sustained responders were significantly younger (P=.005), non-diabetic (P=.005), had higher serum albumin (P=.028), lower alpha-fetoprotein level (P=.026), lower aspartate aminotransferase (AST) (P=.04) levels, and were treatment-naïve (P=.008). In a multivariate regression analysis, the independent predictors of SVR were younger age (P=.016), lower serum AST (P=.012), and being treatment naïve (P=.021).

CONCLUSION

Approximately half of HCV-4 patients who complete the course of combination therapy achieve an SVR, especially if they are young, treatment naA ve and have lower AST levels.

Hepatitis C genotype 4 therapy: increasing options and improving outcomes

Hepatitis C virus genotype 4 (HCV-G4) is prevalent in the Middle East and Africa and has spread to several regions in Europe. HCV-G4 represents a major health problem in Egypt, with a prevalence rate of 13%. Recently, HCV-G4 has been spreading in Europe particularly among intravenous drug users (IDU) populations, who represent the main reservoir for HCV in Europe. This article reviews the current therapeutic strategies for HCV-G4 infections in different populations. HCV-G4 has been considered a difficult-to-treat genotype because of the poor sustained virological response (SVR) rates reported with a conventional interferon (IFN)-based regimen. Pegylated IFN and ribavirin combination therapy was associated with significant improvements in SVR rates that currently exceed 60%, particularly with individualized therapy. Lower response rates have been reported in specific situations, namely chronic HCV-G4 infection in IDUs and patients co-infected with human immunodeficiency virus (HIV). Rapid and early virological responses have been useful tools for determination of the duration of therapy.

IN CONCLUSION

therapy of HCV-G4 has shown significant improvements, with higher sustained response rates and possibilities for a shorter duration. More research is required to optimize therapy in special populations such as IDUs and HIV-co-infected patients.

Hepatitis C genotype 4: What we know and what we don't yet know

Hepatitis C virus genotype 4 (HCV-4) is the most common variant of the hepatitis C virus (HCV) in the Middle East and Africa, particularly Egypt. This region has the highest prevelance of HCV worldwide, with more than 90% of infections due to genotype 4. HCV-4 has recently spread in several Western countries, particularly in Europe, due to variations in population structure, immigration, and routes of transmission. The features of HCV-4 infection and the appropriate therapeutic regimen have not been well characterized. This review discusses the virology, epidemiology, natural history, histology, clinical data, and treatment options for patients with HCV-4 infections. Early reports on the treatment of patients with chronic HCV-4 with conventional interferon (IFN)-alpha monotherapy indicated poor rates of sustained viral response (SVR), which improved slightly when combined with ribavirin. Pegylated IFN and ribavirin combination therapy has dramatically improved the response rates, with recent clinical trials showing rates that exceed 60%. These data can now be used as a platform for further research to define optimal treatment duration and predictors of SVR in patients with HCV-4 infection.

CONCLUSION

HCV-4 infection is spreading beyond its strongholds in Africa and the Middle East. Recent clinical trials show that HCV-4 is not difficult to treat, as the response to treatment may be at an intermediate level compared with genotype 1 and genotypes 2 or 3. Tailored treatment options that are comparable to the treatment approaches for genotype 1, 2, and 3 patients to optimize treatment for each patient are now being developed.

HCV genotype 4 in Belgium: three distinct patterns among patients from European and African origin

BACKGROUND

Considered uncommon in western countries some years ago, hepatitis C virus of genotype 4 is now spreading in some areas of Europe. This is assumed to be due to immigration from a region of high prevalence for this genotype and to propagation among drug users. In the south of Belgium, genotype 4 currently accounts for 10% of hepatitis C virus patients and its prevalence is increasing with time.

OBJECTIVE

To better define the genotype 4 carriers' characteristics.

METHODS

In a database comprising 1726 viraemic hepatitis C virus patients, the files of 85 genotype 4 carriers were reviewed.

RESULTS

Beside the African (58%) and European drug user (15%) subgroups classically described, a third subgroup consisting of European nondrug users (26%) was identified as peculiar: these patients were older, had been mostly contaminated sporadically, presented a great diversity of subtypes, and were mainly of Italian origin. In this subgroup, contamination was supposed to be ancient, having occurred probably in Italy before immigration into Belgium. By contrast, European drug users were infected with only two subtypes (4c/4d and 4), an observation in favour of recent spread. Africans had a great diversity of subtypes, were young, and were mostly contaminated sporadically in their home countries. Despite their epidemiological differences, the clinical management, and in particular the rates of eligibility for treatment, were similar for these three groups.

CONCLUSIONS

Three different patterns of genotype 4 carriers were observed, corresponding to three different spreading profiles. They did not induce, however, different clinical management.

Distribution of hepatitis C virus genotypes in the Middle East

It is well established that hepatitis C develops into cirrhosis of the liver and hepatocellular carcinoma (HCC) both of which are fatal diseases. The World Health Organization estimates that there are at least 21.3 million hepatitis C virus (HCV) carriers in the Eastern Mediterranean countries, which is close to the number of carriers estimated in the Americas and Europe combined. With such a high disease burden of HCV infection in this part of the world, and in light of the new evidence that genotypes may influence the outcome of antiviral therapy, the focus of this review is on the epidemiology and distribution of HCV genotypes in the Eastern Mediterranean countries. Accumulated data show that there are two main patterns for the distribution of HCV genotypes in the Middle East: in the first pattern, genotype 4 is prevalent in most of the Arab countries, and in the second pattern, genotype 1a or 1b predominates in the non-Arab countries. Results from the limited number of clinical trials on the treatment of chronic HCV genotype 4 using peginterferon alfa-2b in combination with ribavirin are encouraging. However, efforts to develop more effective antiviral therapies and the establishment of an effective HCV vaccine remain the largest challenges for the near future.

High prevalence of hepatitis C virus subtypes 4c and 4d in Malaga (Spain): Phylogenetic and epidemiological analyses

Hepatitis C virus (HCV) is a major aetiological agent of chronic hepatitis and it may lead to the development of liver cirrhosis and hepatocellular carcinoma. HCV has been classified into six clades as a result of high genetic variability. A commercial procedure to genotype HCV in 678 patients from Carlos Haya Regional University Hospital, Malaga was used to study the distribution of HCV genotypes in Malaga, southern Spain. A high prevalence of HCV-4 (10.2%) was found. This genotype is found more commonly in Egypt, Central Africa and the Middle East. The distribution of the different subtypes in the 69 patients with HCV-4 was as follows: 4.3% subtype 4e, 7.2% subtype 4a, 11.5% not subtypable, and 76.8% subtype 4c/4d. Of the 53 4c/4d patients, 69% were intravenous drug users and 31% non-intravenous drug users. In order to characterise further the HCV-4c/4d patients, sequences of the non-structural 5B gene (393 bp) were obtained from 36 HCV-4c/4d-infected untreated patients. Phylogenetic tree topologies distinguished clearly the two subtypes: 11 patients were infected by subtype 4c and 25 by 4d. This phylogenetic analysis, reinforced by the epidemiological characteristics, suggests the extension of the HCV-4c and -4d subtypes in the area of Malaga among both intravenous drug users and non-intravenous drug users.

Hepatitis C virus genotype 5 in southern belgium: epidemiological characteristics and response to therapy

Data are scarce on patients infected with hepatitis C virus of genotype 5, due to the low prevalence of this genotype around the world. To better define the characteristics of these patients, we reviewed the files of 16 genotype 5 patients. Mean age was 38 +/- 14. All patients were of European origin. Most of them (75%) had been contaminated by transfusion within a short time period (between 1980 and 1991). There were no intravenous drug addicts. Seven patients received treatment. One patient did not respond to interferon (IFN) monotherapy. Of four patients treated with IFN and ribavirin, three became sustained viral responders. Two patients treated with pegylated IFN and ribavirin became sustained viral responders. In our region, genotype 5 patients seem to have been contaminated within a relatively short time period. Treatment with IFN or pegylated IFN and ribavirin gave a high rate (83%) of sustained viral responses.

Chronic hepatitis C: genotypes 4 to 9

Infection with hepatitis C virus (HCV) genotypes 1, 2, or 3 is widely distributed throughout the world and has been the focus of the majority of studies on the epidemiology and treatment of chronic hepatitis C. Infection with HCV genotypes 4 through 9 is prevalent in some geographic areas where the disease burden of chronic hepatitis C approaches endemic levels (eg, HCV genotype 4 in Egypt where there is an HCV infection prevalence of approximately 18%). This article reviews the existing literature, which suggests that chronic hepatitis C with genotypes 4 through 9 may exhibit epidemiologic, clinical, and treatment outcome differences from infection with genotypes 1, 2, or 3.

Alpha-interferon with ribavirin in the treatment of hemodialysis patients with hepatitis C

INTRODUCTION

Hepatitis C Viral (HCV) infection is the leading cause of chronic liver disease in end-stage renal disease patients (ESRD). The impact of HCV on patient and graft survival posttransplantation is controversial. The most successful approach is to eliminate the virus while the patient is on dialysis prior to transplantation. The main aim of this pilot study was to assess the efficacy of combined alpha-interferon (alpha-IFN) and ribavirin treatment of HCV hemodialysis (HDx) patients, by comparing the sustained virological response to that obtained by local historical data on treatment with alpha-IFN alone. A secondary aim was to establish the optimal therapeutic dose of ribavirin in this regimen.

METHODS

Twenty HCV-HDx patients who were histologically (liver biopsy) and virologically (HCV-PCR)-positive were selected randomly. They received combination therapy with 3 million units (MU) of alpha-IFN and 200 mg of ribavirin three times a week. Initially nine patients were treated for 24 weeks. Later, another 11 patients were randomly selected to give the combination for 48 weeks.

RESULTS

Six of the nine patients who were treated for 24 weeks (66%) became HCV-PCR-negative by the end of the treatment period. They continued to have a sustain virologic response at 6 months after the cessation of therapy. Six of the 11 patients (55%) who were treated for 48 weeks became HCV-PCR-negative at the end, and at 6 months after cessation of treatment. Of the first six responders, 4 (66%) maintained a sustained virologic response at 1 year postcessation of therapy. Nine of the 11 patients had genotype 4 and 1. No side effects were reported for a ribavirin dose of 200 mg three times a week.

CONCLUSION

This pilot study suggests that combination treatment for 24 weeks and 48 weeks with 3 MU alpha-IFN and 200 mg ribavirin three times a week, elicited a sustained virologic response in HDx patients with HCV infection better than IFN alone with minimal side effects. A prospective, double-blind, controlled study using pegylated INF plus ribavirin is currently underway.

HCV genotype 4--an emerging threat as a cause of chronic liver disease in Indian (south) patients

BACKGROUND

Hepatitis C virus (HCV) genotyping is relevant for the delivery of effective antiviral therapy. HCV genotypes are geographically restricted with genotype 4, which is resistant to therapy, traditionally considered to be confined to the Middle East and Africa. We report here on the occurrence of HCV genotype 4 in Indian (South) patients.

OBJECTIVES

1) To highlight the occurrence of HCV genotype 4 in the patient population attending a tertiary care hospital in south India. 2) To ascertain the difference in HCV viral loads and alanine aminotransferase (ALT) values between patients infected with HCV genotype 4 and those infected with the other two most commonly detected genotypes in this patient population viz., HCV genotypes 1 and 3. 3) To assess the genetic relatedness of the Indian strains to Genbank sequences, which we report for the first time.

STUDY DESIGN

The study group consisted of 125 HCV infected, untreated patients who had been genotyped using type specific primers. Eight of the nine samples classified as HCV genotype 4 by this technique were subjected to nucleotide sequencing. Viral load estimations were carried out. Information on possible risk factors and ALT values were obtained from hospital records. Statistical analyses were carried out to compare viral loads and ALT values across genotypes. A phylogenetic tree was constructed and the genetic relatedness of the strains was assessed through sequence analysis.

RESULTS

HCV genotype 4 was detected in nine of 125 (7.2%) patients. Eight of the nine were subjected to nucleotide sequencing and all strains were confirmed as HCV genotype 4. Six of the eight strains were closely related, with two strains being phylogenetically diverse.

CONCLUSIONS

HCV genotype 4 is detected in a significant minority of HCV infected patients in India. This finding should be considered in designing strategies prior to initiation of therapy in Indian patients infected with HCV.

Meta-analysis: a randomized trial of peginterferon plus ribavirin for the initial treatment of chronic hepatitis C genotype 4

BACKGROUND

Guidelines for treatment of patients infected with hepatitis C virus genotype 4 are not available.

AIM

To perform a meta-analysis of randomized controlled trials comparing peginterferon plus ribavirin with interferon plus ribavirin treatment in treatment-naive patients infected with chronic hepatitis C virus genotype 4.

METHODS

The outcome measure was sustained virologic response. The measure of association employed was relative risk calculated by the random-effect model, with heterogeneity, sensitivity and subgroup analyses.

RESULTS

Of the 565 studies screened, six randomized controlled trials including 424 patients (peginterferon plus ribavirin 219, interferon plus ribavirin 205) were analysed. Duration of therapy was 1 year in all trials. Sustained virological response obtained with peginterferon plus ribavirin (55%) was significantly higher than with interferon plus ribavirin (30%) [relative risk, 1.71 (95% confidence interval, 1.15-2.56); P = 0.0088]. In the subgroup analyses, sustained virological response in trials using standard-dose ribavirin (1000 or 1200 mg/day) was 72% as against 45.8% in trials using low-dose ribavirin (800 mg/day) (P = 0.01). Further sub-group analyses for treatment duration, body weight, viral load and cirrhosis could not be performed because of lack of relevant data.

CONCLUSION

Treatment-naive patients infected with hepatitis C virus genotype 4 should be treated with peginterferon plus standard-dose ribavirin for 1 year, with an expected sustained virological response rate of 72%.

Peginterferon-alpha-2a (40kD) plus ribavirin: a review of its use in the management of chronic hepatitis C

Pegylation of interferon-alpha-2a is associated with improved sustained virological response rates in patients with chronic hepatitis C. Subsequently, combination therapy with peginterferon-alpha-2a (40kD) [Pegasys] and ribavirin (Copegus trade mark, Rebetol) was investigated to establish if the efficacy of peginterferon-alpha-2a (40kD) monotherapy could be further enhanced. Subcutaneous peginterferon-alpha-2a (40kD) was administered at a dosage of 180 micro g once weekly and oral ribavirin was usually administered at a dosage of 1000 or 1200 mg/day. In treatment-naive patients with chronic hepatitis C, the sustained virological response rate (assessed 24 weeks after the end of a 48-week treatment period) was significantly higher in peginterferon-alpha-2a (40kD) plus ribavirin recipients than in peginterferon-alpha-2a (40kD) plus placebo recipients or interferon-alpha-2b plus ribavirin recipients (56% vs 29% and 44%). Retrospective analysis revealed that peginterferon-alpha-2a (40kD) plus ribavirin recipients who did not achieve an early virological response were unlikely to achieve a sustained response. Treatment with peginterferon-alpha-2a (40kD) plus another antiviral agent (ribavirin, mycophenolate mofetil, amantadine, or ribavirin and amantadine) was beneficial in patients with chronic hepatitis C who had relapsed during or after, or had not responded to, treatment with interferon-alpha-2b plus ribavirin. In the relapse study, sustained virological response rates in recipients of peginterferon-alpha-2a (40kD) plus ribavirin were 45% with and 38% without amantadine. Peginterferon-alpha-2a (40kD) plus ribavirin appears beneficial in patients with chronic hepatitis C considered difficult to treat (e.g. patients infected with hepatitis C virus genotype 4, African-American patients, patients with advanced fibrosis or cirrhosis and patients co-infected with HIV). Flu-like symptoms and depression occurred significantly less frequently with peginterferon-alpha-2a (40kD) plus ribavirin than with interferon-alpha-2b plus ribavirin. Similar proportions of patients receiving peginterferon-alpha-2a (40kD) plus ribavirin, peginterferon-alpha-2a (40kD) plus placebo and interferon-alpha-2b plus ribavirin withdrew from treatment because of laboratory abnormalities or other adverse events. In conclusion, combination therapy comprising subcutaneous peginterferon-alpha-2a (40kD) and oral ribavirin is an important new treatment option for chronic hepatitis C. Peginterferon-alpha-2a (40kD) plus oral ribavirin is significantly more effective than peginterferon-alpha-2a (40kD) monotherapy or interferon-alpha-2b plus ribavirin at inducing a sustained virological response in treatment-naive patients with chronic hepatitis C. Preliminary data suggest that peginterferon-alpha-2a (40kD) plus ribavirin is also beneficial in treatment-experienced patients and in patients who have traditionally been considered difficult to treat. Combination therapy with peginterferon-alpha-2a (40kD) and oral ribavirin is poised to become a valuable first-line treatment option in chronic hepatitis C.

Distribution of the different genotypes of HCV among patients attending a tertiary care hospital in south India

BACKGROUND

Genotyping of the hepatitis C virus (HCV) and assessment of viral load is important for designing therapeutic strategies and region specific diagnostic assays.

OBJECTIVES

To determine the distribution of HCV genotypes among patients attending a tertiary care hospital in south India, and to correlate this with viral load.

STUDY DESIGN

Ninety HCV RNA positive patients were recruited for the study. HCV genotyping was carried out using type-specific primers from the core region of the viral genome [J. Clin. Microbiol. 35 (1997) 201]. Viral load estimations were carried out using the Amplicor HCV Monitor (Versions 1.5 and 2, Roche Diagnostics, Branchburg, NJ, USA). Clinical details were elicited from patients' hospital records.

RESULTS

Genotype 3 was detected most frequently (62.2%) followed by infection with HCV genotype 1 (18.8%). There was no significant difference seen in alanine aminotransferase (ALT) values between the two genotypes. Genotype 1 was associated with a significantly higher viral load as compared with genotype 3 (P=0.001). Parenteral transmission accounted for 61% of all infection caused. Infection with genotype 1 was significantly associated with a history of haemodialysis (P=0.01). Genotype 3 was detected more frequently in patients from east India, as compared with its detection in patients from south India (P=0.004). Similarly, genotype 1 was detected with greater frequency in individuals from south India as compared with patients from east India (P=0.004). The concordance between Ohno's genotyping assay and nucleotide sequencing, for genotypes 1 and 3, was 75%.

CONCLUSIONS

HCV genotypes 1 and 3 accounted for 81% of HCV infections in patients from this geographical region. HCV genotype distribution showed regional differences and genotype 1 was associated with higher viral loads. Parenteral transmission was the major route for acquisition of HCV infection. Ohno's type-specific primer based genotyping assay can be used for distinguishing between HCV genotype 1 and non-1 HCV genotypes in laboratories that do not possess nucleotide sequencing facilities.

Three cases of infection with hepatitis C virus genotype 5 among Brazilian hepatitis patients

During the course of routine genotyping of hepatitis C virus isolates by 5' noncoding region sequencing, three samples were found to bear genotype 5-specific nucleotides. A serotyping method was subsequently applied and confirmed the finding. This is the first report of the occurrence of genotype 5 in Brazil.

Elevated levels of interleukin-8 in serum are associated with hepatitis C virus infection and resistance to interferon therapy

Hepatitis C virus (HCV), a major cause of liver disease worldwide, is frequently resistant to the antiviral alpha interferon (IFN). We have recently found that the HCV NS5A protein induces expression of the proinflammatory chemokine IL-8 to partially inhibit the antiviral actions of IFN in vitro. To extend these observations, in the present study we examined the relationship between levels of IL-8 in serum, HCV infection, and biochemical response to IFN therapy. Levels of IL-8 were significantly elevated in 132 HCV-infected patients compared to levels in 32 normal healthy subjects and were also significantly higher in patients who did not respond to IFN therapy than in patients who did respond to therapy. This study suggests that HCV-induced changes in levels of chemokine and cytokine expression may be involved in HCV antiviral resistance, persistence, and pathogenesis.

The epidemic behavior of the hepatitis C virus

Hepatitis C virus (HCV) is a leading worldwide cause of liver disease. Here, we use a new model of HCV spread to investigate the epidemic behavior of the virus and to estimate its basic reproductive number from gene sequence data. We find significant differences in epidemic behavior among HCV subtypes and suggest that these differences are largely the result of subtype-specific transmission patterns. Our model builds a bridge between the disciplines of population genetics and mathematical epidemiology by using pathogen gene sequences to infer the population dynamic history of an infectious disease.

Phylogenetic analyses confirm the high prevalence of hepatitis C virus (HCV) type 4 in the Seine-Saint-Denis district (France) and indicate seven different HCV-4 subtypes linked to two different epidemiological patterns

Hepatitis C virus (HCV) has been classified into six clades as a result of high genetic variability. In the Seine-Saint-Denis district of north-east Paris, the prevalence of HCV-4, which usually infects populations from Africa or the Middle East, is twice as high as that recorded for the whole of continental France (10.2 versus 4.5%). Although the pathogenicity of HCV-4 remains unknown, resistance of HCV-4 to therapy appears to be similar to that observed for HCV-1. In order to characterize the epidemiology of HCV-4 in Paris, sequences of the non-structural 5B gene (332 bp) were obtained from 38 HCV-4-infected patients. Extensive phylogenetic analyses indicated seven different HCV-4 subtypes. Moreover, phylogenetic tree topologies clearly distinguished two epidemiological profiles. The first profile (52.6% of patients) reflects the intra-suburban emergence of two distinct HCV-4 subclades occurring mainly among intravenous drug users (65% of patients). The second profile shows six subclades [HCV-4a, -4f, -4h, -4k, -4a(B) and a new sequence] and accounts for patients from Africa (Egypt and sub-Saharan countries) who have unknown risk factors (77.8% of patients) and in whom no recent diffusion of HCV-4 is evident. This study indicates the high diversity of HCV-4 and the extension of HCV-4a and -4d subclades among drug users in FRANCE:

Molecular characterisation of HCV genotype 4 isolates circulating in Italy

The characteristics of genotype 4 subtype variability of HCV isolates circulating in Italy were studied. The viral isolates were identified from 736 HCV-RNA positive sera originated from seroepidemiological studies undertaken in 4 different regions of North, South Italy and Sardinia. 24 out of 28 genotype 4 isolates (86%) were classified by phylogenetic analysis of E1 genome region (915-1128) as belonging to subtype 4d (Neighbour Joining Method). Three isolates classified as subtype 4a were detected in haemophilic patients, possibly related to infections from blood products. One isolate classified as a new subtype derived from an Eritrean patient subjected to haemodialysis. Very high genome homogeneity (mean 4.3%) was shown by genetic comparisons (DNA dist programs Phylip Package) for all the 4d isolates relative to the studies performed in Veneto, Calabria and Sardinia and originated from subjects from the general population and outpatients (19 subtype 4d isolates out of 24). In the 3 studies different prevalence rates of HCV genotype 4 (3.1%, 1. 3%, 14% respectively) were found. In contrast a considerable degree of heterogeneity, both intragroup and with the other groups (mean 8. 2% and 8.7%, respectively) was observed among subtype 4d isolates identified in the patients of a haemodialysis centre in Apulia region. In conclusion the subtype 4d of genotype 4 was highly prevalent and endemic in Italy. An elevated level of viral heterogeneity was observed in one study carried out in a region of Southern Italy. This can be related to a longer period of past endemicity of this genotype and to a high level of exposure to reinfections in particular categories of patients such as haemodialysis patients.

Hepatitis C virus genotyping by polymerase chain reaction and DNA enzyme immunoassay among Saudi patients in the Western Province, Saudi Arabia

BACKGROUND

The distribution of hepatitis C virus (HCV) genotypes in the Western Province of Saudi Arabia is unknown. The purpose of our study was to determine the prevalent HCV genotypes among HCV seropositive Saudi patients in the Western Province, and to study the relationship between types/subtypes, clinical status and liver histology.

PATIENTS AND METHODS

Serum samples were collected from 140 consecutive patients attending the Hepatology Clinic with varying grades of liver diseases, high alanine transferase (ALT) for >6 months, positive HCV, qualitative PCR, and who had had liver biopsy. HCV genotyping was determined on patients who had tested positive by both HCV enzyme immunoassay (EIA) and recombinant immunoblot assay (RIBA).

RESULTS

Of the 140 patients, 97 (69.2%) had genotype 4, 18 (12.8%) had genotype 1a, and 16 (11.4%) had genotype 1b. Genotypes 2b and 5 were found in two patients (1.4%) each, while 5 patients (3.6%) had mixed infections with genotypes 4 and 5. Of the 97 patients infected with genotype 4, 84 (86.6%) had chronic active hepatitis (CAH), two (2.1%) had CAH with active cirrhosis, 9 (9.3%) had cirrhosis and two (2.1%) had normal liver histology (NLH).

CONCLUSION

The most prevalent HCV genotype in the Western Province of Saudi Arabia was genotype 4 (69.2%). Genotype 1b was encountered in 16 (11.4%) patients. For the first time, genotype 5 was identified in the Western Province of Saudi Arabia. Genotypes 1b and 4 were associated with different histological grades of liver disease.