Occult HBV Infection: A Case Series at a Military Treatment Facility

Occult HBV infection (OBI) is defined as the presence of detectable hepatitis B virus (HBV) DNA in HBV surface antigen (HBsAg) negative individuals. Rarely, OBI is attributed to mutant HBV that cannot be detected by commercial assays, but most cases occur in the setting of chronic hepatitis B, particularly infection with wild-type viruses associated with strong HBV suppression. OBI is a high-risk diagnosis as it is associated with multiple complications: HBV reactivation in immunocompromised states, transmission of HBV, progression of liver disease, and hepatocellular carcinoma. The diagnosis is also easy to overlook, as the negative HBsAg in such cases can be falsely reassuring. This case series describes four male patients (mean age 51) who were diagnosed with OBI in the same military treatment facility between February 2018 and October 2018. Two of the four patients were active duty service members at the time of diagnosis. These patients had variable clinical presentations and outcomes. This case series illustrates the clinical significance of OBI and the importance of screening for OBI in HBsAg negative patients with signs of chronic or severe hepatic inflammation. It also prompts an intriguing question regarding the prevalence of both HBV and OBI in the United States military and whether or not routine screening for HBV should be implemented in this population. Further study is warranted to determine if adding HBV core antibody to a universally employed screening regimen would be beneficial.