RESUMO
BACKGROUND: Despite considerable progress in the treatment of chronic hepatitis C, many countries do not have access to these new treatments. OBJECTIVES: Predictive markers of response to treatment are therefore necessary before initiating with historical combination therapy (PEG-IFN+ribavirin) for these populations. STUDY DESIGN: We therefore evaluated the influence of IL28B polymorphisms on treatment response and Inosine Triphosphate (ITPA) polymorphisms on the incidence of anaemia in a population of 120 Tunisian patients infected with HCV genotype 1b and treated. RESULTS: The frequencies of favourable IL28B genotypes were 47% (CC for rs12979860) and 63% (TT for rs8099117). Patients in whom favourable IL28B alleles were identified had a higher chance of successful therapy: 82% for CC (rs12979860) and 75% for TT (rs8099117). Viral load decline during the first twelve weeks of treatment was more pronounced in patients with a favourable genotype (p<0.0001). For patients with an unfavourable genotype, the second phase of viral decline was more pronounced in patients with SVR. A viral load decline cut-off of 2.68logIU/mL at week 12 was best suited to discriminate responders from non-responders with an odds ratio of 40 (95% CI:11.53-170.3). Analysis of ITPA polymorphisms revealed that 16% of Tunisian patients presented ITPase deficiency. None of these patients experienced a decline of ribavirin doses during treatment versus 67% for patients without ITPase deficiency (p<0.001). CONCLUSION: These data obtained in a Tunisian population should optimize before and during treatment the chances of success for treatments currently available in Tunisia for chronic HCV infection.