Olfa Bahri

Hepatocellular carcinoma (HCC) is a major public health issue in Africa. In Tunisia, hepatitis B virus (HBV) is known to be an important risk factor for HCC in the south of the country, but the role played by hepatitis C virus (HCV) still remains unclear. The aim of the current case-control study was to identify risk factors for HCC development in the northern part of the country. Clinical and biological data including viral hepatitis status (serological and molecular) and non-infectious risk factors from 73 patients with HCC and 70 control subjects without hepatic diseases were collected. The mean age of the patients was 63 ± 10 years, and the ratio of males to females was 1.1. HCC occurred in cirrhotic liver in 72.0% of the cases. HCV infection was the dominant risk factor (64.3% of cases); the presence of HBV was observed in 53.4% of the cases. Occult hepatitis B and C were implicated, respectively, in 30.1% and 9.6% of the cases. HCV genotype 1b was predominant. Patients originating from western Tunisia formed a homogeneous group, characterized by significantly higher rates of tattoos or scarifications (83%) and HCV infection (80%) than those from other parts of the country. Chronic HCV infection is currently the primary risk factor for HCC in Tunisia; HBV infection remains frequent in its overt or occult infection forms. Traditional esthetic practices apparently contribute to increasing the burden of terminal liver diseases in western Tunisia.

Background: Hepatitis B virus (HBV) infection is a public health problem in developing countries. HBV genotypes play major role in the evolution of infection since they were involved in different clinical presentations and response to treatment. Objectives: This study was conducted to determine circulating HBV genotypes in the country and to evaluate the efficiency of restriction fragment length polymorphism (RFLP) analysis for HBV genotyping. Patients and Methods: We investigated 98 samples collected from patients chronically infected with HBV. HBV genotypes were determined by analysis of patterns obtained after amplification in Pre-S region and digestion of the amplicon by two endonucleases AvaII and DpnII. Obtained results were confirmed by partial sequencing in the same region. Results: Two different HBV genotypes were detected in this study, Genotype D (in 95. 9%) and Genotype A (in 4.1%). Seventy-four samples (75.5%) were successfully genotyped with RFLP analysis and all classified as genotype D. The remaining 24 samples (24.5%) which were un-genotyped by RFLP analysis, were classified by partial sequencing of the pre-S region as HBV genotype D (20 samples, 20.4%) and genotype A (4 samples, 4.1%). Atypical profiles were significantly associated with advanced liver disease (P = 0.001) as well as older age (P < 0.05). Conclusions: Several previous studies used PCR-RFLP to genotype HBV; however, we showed the high risk to obtain atypical profiles, especially in advanced stages of chronic infection, with as results difficulties to genotype the virus. These profiles resulted from the accumulation of mutations during natural course of infection resulting in a modification in restriction sites for enzymes. So, we recommended completing the investigation by partial sequencing to confirm obtained results. Keywords: Hepatitis B Virus; Genotype; Restriction Fragment Length Polymorphism; Direct Sequencing

This paper reports hepatitis C virus (HCV) prevalence, genotypes and phylogenetic characteristics in 95 haemophilic Tunisian patients. The studied population included 3 groups of patients according to their date of birth: before 1985 when inactivation procedures for clotting factors was introduced, between 1985 and 1994 when systematic anti-HCV screening of Tunisian blood donors was introduced and after this date. HCV infection was assessed by serological and molecular commercial tests. Genotypes were determined using the INNO-LiPA HCV test and by partial sequencing in the NS5b genomic region. Phylogenetic analyses were performed by comparing NS5b sequences of Tunisian haemophiliacs to published sequences. HCV infection was detected in 50.5% of cases with a significant decrease according to age. Subtype la was the most prevalent followed by subtype 1b (52.6% vs 44.7%); it was more frequent among haemophiliacs born before 1985. NS5b sequences were different from those obtained from non-haemophilic Tunisian patients and showed nucleic affiliation with HCV isolates from the USA. These findings suggest an infection through clotting factors imported to Tunisia and frequently manufactured from US blood donors. In contrast, subtype 1b showed approximately the same distribution among patients born before and after 1985; NS5b sequences from haemophiliacs were randomly distributed among other Tunisian sequences, favouring a transmission through cryoprecipitates prepared from Tunisian blood donors.