Summary Are newly diagnosed patients with HBV and HCV infection different ? Comparison between 2 prospective registries of the Belgian Association for the Study of the Liver Bénédicte De Vroey 1, Christophe Moreno 2, Wim Laleman 3, Marc van Gossum 4, Isabelle Colle 5, Chantal de Galocsy 6, Philippe Langlet 7, Geert Robaeys 8, Hans Orlent 9, Peter Michielsen 10, Jean Delwaide 11, Hendrik Reynaert 12, Michael Adler 2, Jean Henrion 1, Pierre Deltenre 1 1 Hôpital de Jolimont, Haine-Saint-Paul, Belgium, 2 Hôpital Erasme, Brussels, Belgium, 3 KUL Leuven, Belgium, 4 CHU Saint-Pierre, Brussels, Belgium, 5 UZ, Gent, Belgium, 6 Hôpitaux Iris Sud Bracops, Brussels, Belgium, 7 CHU Brugmann, Brussels, Belgium, 8 Ziekenhuis Oost-Limburg, Genk, Belgium, 9 AZ St Jan, Brugge, Belgium, 10 UZ Antwerpen, Edegem, Belgium, 11 CHU, Liège, Belgium, 12 UZ, Brussels, Belgium The authors have no financial disclosure related to this study Introduction: Hepatitis B (HBV) and C (HCV) infections share many epidemiological and clinical similarities but exhibit also important differences. Moreover, their epidemiological characteristics are evolving in western countries. Nationwide studies comparing representative samples of patients newly diagnosed with HBV or HCV infections have not been reported. Aim: To compare the main epidemiological, biological and histological characteristics of patients with newly diagnosed HBV or HCV infection in Belgium, and to compare their management. Methods: Data of patients with newly diagnosed HBV or HVC infection were extracted from two Belgian registries (HBsAg carriers registry, and observational survey of hepatitis C, ). Results: 705 patients (387 with HBV and 318 with HCV) were included. Compared to HCV patients, HBV patients were younger (36 vs. 44 years, p 2ULN (15 vs. 38%, p 2ULN (p=0.01) and activity score >2 (p=0.004). HBV patients were less frequently considered for treatment (25 vs. 47%, p<0.0001) than HCV patients. Conclusions: Newly diagnosed HBV and HCV patients disclosed different epidemiological characteristics that should be taken into account for screening. Management of HBV and HCV patients differed, HBV patients undergoing less frequently a liver biopsy and being less frequently considered for treatment.. Conclusions 1/ In Belgium, newly diagnosed HBV and HCV patients disclose different epidemiological characteristics that should be taken into account for screening. 2/ Management of HBV and HCV patients also differs, HBV patients undergoing less frequently a liver biopsy and being less frequently considered for treatment. Introduction Hepatitis B (HBV) and C (HCV) infections share many epidemiological and clinical similarities but exhibit also important differences. Moreover, their epidemiological characteristics are evolving in western countries. Nationwide studies comparing representative samples of patients newly diagnosed with HBV or HCV infections have not been reported. Aim To compare the main epidemiological, biological and histological characteristics of patients with newly diagnosed HBV or HCV infection in Belgium and to compare their management. Methods Data of patients with newly diagnosed HBV or HCV infection were extracted from two Belgian registries (HBsAg carriers registry, and observational survey of hepatitis C, ). Patients HBV patients n=387 HCV patients n=318 p value Mean age (years)3644< Sex ratio (men/women)69% / 31%56% / 44%< Origin Caucasian43%86%< Black African32%9%< Other25%5%< Risk factors for infection Transfusion9%33%< IV drug use6%43%< Sexual behavior40%1%< Familial transmission30%1%< Histological parameters and managementBiological parameters Predictors of F3/4 in multivariate analysis Older agep=0.003 Male sexp=0.02 HBV infectionp=0.03 ALT>2ULNp=0.01 Activity score >2p=0.004