title: Epidemiological study of genotypes of hepatitis B virus in northern Portugal.
abstract: While the overall prevalence of hepatitis B virus (HBV) infection in Portugal is around 1%, there are no published studies examining HBV genotypes in this country. This study aimed to survey HBV genotypes in the northern Portugal and to examine the possible associations between genotypes and gender, viral transmission routes, viral markers, viral load, and biochemical tests of liver function. The study sample consists of 340 patients with HBV infection of whom 42.9% were women. Tests were carried out for HBV genotypes and biochemical liver function while demographic information, including alcohol intake, was obtained from the patient files. The results indicate the predominance of genotype D (60.3%) and genotype A (31.5%). Intrafamilial transmission was predominant in female patients, while males were infected in equal proportions by perinatal, sexual, and intrafamilial transmission. Absence of HBeAg was found in a significantly smaller proportion of female patients with genotype D as compared to A (56.6% vs. 82.1%, P = 0.028). High viral load was associated significantly and independently with genotype D and HBeAg. Both alanine and aspartate aminotransferases (ALT and AST) were associated with gender and HBeAg. Thus, genotypes A and D were found to be the most prevalent in the north of Portugal. Patients infected with genotype D had higher levels of HBV DNA. HBeAg was associated with genotype D, viral load, and ALT and AST.
authors.affiliation: Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Mota
authors.forename: Fátima
authors.initials: F
authors.lastname: Guedes
authors.forename: Jorge
authors.initials: J
authors.lastname: Areias
authors.forename: Luciana
authors.initials: L
authors.lastname: Pinho
authors.forename: Margarida Fonseca
authors.initials: MF
authors.lastname: Cardoso
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000097:blood; D005192:Family Health; D005260:Female; D005838:Genotype; D006509:Hepatitis B / Q000453:epidemiology* / Q000635:transmission / Q000821:virology*; D006513:Hepatitis B e Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D011174:Portugal / Q000453:epidemiology; D019562:Viral Load
chemical_list: D006513:Hepatitis B e Antigens; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase