Epidemiological and genotypic profile of hepatitis B virus infection in Northern Portugal

OBJECTIVE: To describe the epidemiological and genotypic profile of chronic hepatitis B infection in Northern Portugal. METHODS: This survey comprised 358 subjects with positive serology for hepatitis B antigen for at least six months, recruited from specialist appointments in two hospitals in Northern Portugal between 2008 and 2009. Data were obtained from patient files, laboratory tests performed at the time of viral genotyping, echograms and/or ultrasonogram results, and liver biopsies. Demographic characteristics, viral markers, viral load and genotype, and severity of liver disease were evaluated and compared between sexes. RESULTS: Genotypes A and D were predominant in both sexes. Intrafamilial transmission occurred mostly among female patients. One-third of females and 58,9% of males showed alcohol intake above 20 g/day. Absence of AgHBe was similar in both sexes (p = 0.662). Elevated biochemical parameters and presence of necroinflammatory activity and steatosis in liver biopsies were more frequent among male patients (p = 0.003). CONCLUSIONS: Differences in terms of route of HBV infection between men and women may be a consequence of gender-associated risk behaviors. Excessive alcohol intake is more frequent among males than females, as is more severe liver disease.