Acute hepatitis B infection escaping vaccination: A case report.

RATIONALE: Hepatitis B virus (HBV) is an important cause of acute and chronic infectious hepatitis globally. Vaccines against HBV are widely available and generally lead to lifelong protection against chronic infection, disease, and infectivity. Vaccine failure, in which a person fails to form sufficiently high antibody titers, occurs in 5% to 10% of the population. Vaccine failure due to mutations in the virus, enabling vaccine escape, on the other hand, is very rare.

PATIENT CONCERNS: A 72-year-old man presented with heartburn complaints. In clinical examination, an enlarged liver was found, and subsequent testing showed abnormal liver function. He was fully vaccinated against HBV.

DIAGNOSES: Positive test results for hepatitis B surface antigen, immunoglobulin G and immunoglobulin M antibodies against hepatitis B core antigen, and antibodies against hepatitis B e and surface antigen were found. HBV DNA was positive (14,000 IU/mL). These results indicated an acute HBV infection.

INTERVENTIONS: A rare mutation in the S-gene of HBV, D144A, was found.

OUTCOMES: The patient recovered without treatment.

LESSONS: We describe a case of acute HBV infection in a fully vaccinated person with high post-vaccination titers due to a rare mutation in the S-gene of HBV, which has previously been associated with vaccine escape. We describe the epidemiology of such mutations and the public health consequences of discovering such a strain in the community.