Severe acute hepatitis B in a treatment-naïve patient with antiviral drug resistant mutations in the polymerase gene.

This is a case of 62 years old Caucasian treatment-naïve patient who developed a severe acute hepatitis B infection soon after a trip to Thailand. The infection was due to genotype C HBV which was found to be resistant to lamivudine and telbivudine. The patient was treated with tenofovir resulting in complete suppression of viral replication and complete clinical and laboratory remission of acute hepatitis. Later the patient also developed seroconversion of HBeAg to anti-HBe and of HBsAg to anti-HBs. This case demonstrates that mutations of HBV polymerase associated with lamivudine, telbivudine, and adefovir resistance can be present also in untreated patients with severe acute hepatitis B. This suggests that in the clinical context, which represents a life threatening condition, a baseline resistance-testing should be an additional marker in the diagnostic evaluation process. Finally, this case report seems to support the use of tenofovir for the immediate treatment of severe acute hepatitis B.