Hepatitis B virus genotypes among chronic hepatitis B patients from Baghdad, Iraq and their impact on liver function

Hepatitis B virus (HBV) infection is a significant global health problem. Populations of different ethnicities show great heterogeneity in HBV genotype frequency distributions. A cross-sectional study was conducted during June-October 2018 to determine frequency of HBV genotypes among chronic HBV patients from Baghdad, Iraq. The method of detection was nested polymerase chain reaction system. Further, the study assessed the impact of HBV genotypes on serum level of liver-function tests: total serum bilirubin, alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase. Eighty chronic HBV patients were enrolled in the study. Six HBV genotypes were identified (A, B, C, D, E and F). The most frequently encountered genotypes were B and F (72.5% each), while E genotype was the least observed with frequency of 12.5%. In addition, the majority of patients (77.5%) showed mixed HBV genotypes (two, three, four or five) with different genotypic combinations. Single HBV genotype patients represented only 17.5%. When patients positive for mixed HBV genotypes were inspected for serum level of liver-function parameters, only alkaline phosphatase showed a significant difference. It exhibited a gradual increase median that positively paralleled the number of positive genotypes; patients positive for one genotype showed the lowest median (87.0 U/L), while patients positive for five genotypes demonstrated the highest median (130 U/L). In conclusion, the HBV genotypes B and F were the most frequent among the investigated sample of Iraqi chronic HBV patients from Baghdad.