Infectious source factors affecting the severity of sexually transmitted acute hepatitis due to hepatitis B virus genotype C.

Objective: The aim of this study was to identify clinical features and virological aspects of infectious sources that are related to the severity of sexually transmitted acute hepatitis B virus (HBV) infection in patients, especially in cases of genotype C.

Methods: Nineteen patients with acute HBV infection, 10 classified with severe acute hepatitis (SH) (prothrombin time; PT <40%) and 9 with typical acute hepatitis (AH) (PT >40%), and their infectious sources (all were sexual partners) were studied. Infectious source factors were analyzed in relation to the severity of hepatitis in the patients' partners.

Results: The nucleotide homology of HBV-DNA between each pair was >/=98.9%. Sixteen were infected with HBV genotype C. Among the 16 infectious sources, age, numbers with elevated alanine aminotransferase (ALT, 7/9 vs. 1/7), anti-HBe positivity (8/9 vs. 1/7) and core promoter mutations at nt 1762 (7/9 vs. 1/7), nt 1764 (8/9 vs. 1/7) and precore mutation at nt 1896 (8/9 vs. 1/7) were significantly higher in the sources of SH than in those of AH.

Conclusion: Higher age, elevated ALT, anti-HBe positivity and core promoter/precore mutations were possible risk factors for an infectious source of the severe form of sexually transmitted acute hepatitis due to HBV genotype C.