[First case of hepatitis B virus genotype H infection in Turkey].

Clinical studies reported from Turkey indicate that hepatitis B virus (HBV) genotype D is more prevalent than other genotypes. Epidemiological and clinical information on genotype H infection is currently limited. Genotype H infection is most likely due to its regional (Central and South America) prevalence throughout the world. The aim of this report is to present the first HBV genotype H infection in a chronic hepatitis B patient in Turkey. Laboratory findings of a 42 years old male patient admitted to our hospital revealed HBsAg (+), anti-HBs (-), HBeAg (-), anti-HBe (+), anti-HBc IgM (-), anti-HBc IgG (+), anti-HAV IgG (+), HBV-DNA: 5.689.776 IU/ml and high liver enzymes (ALT: 223 U/L, AST: 121 U/L). History of the patient indicated no risk factor (intravenous drug use, blood transfusion, suspicious sexual contact) related to HBV transmission. Since liver ultrasonography showed multiple hemangiomas, biopsy was performed and histologic activity index was found as 6/18 and fibrosis as 2/6, according to modified Knodell score system. HBV DNA isolated from the serum sample of the patient was amplified by polymerase chain reaction and polymerase gene segment of HBV was directly sequenced. UPGMA method was used for phylogenetic analysis, and the genotype of the virus was identified accordingly. The nucleotide sequence was compared to those from the international DNA data bank (GenBank). The genotyping of the patient revealed that the isolated HBV was genotype H. Treatment with tenofovir disoproxil fumarate was initiated and the patient responded to the treatment. This finding suggested that other HBV genotypes, except the predominant genotype D may also be in circulation in Turkey. In conclusion, detection of epidemiologic and molecular characteristics of HBV genotype H which is related to chronic hepatitis, seems to be necessary in order to better understand its circulation and progression around the world.