Abstract
Background
Intravenous Ig (IVIG) is used in the management of a wide array of medical conditions. Passive transfer of hepatitis B core antibody (anti‐HBc) following IVIG administration is a well‐recognized, but often underappreciated phenomenon that can complicate the interpretation of hepatitis B serologies. Failure to recognize passive anti‐HBc transfer may lead to unnecessary diagnostic evaluation and interventions, as well as delays in needed immunosuppressive therapy.
Cases
This report presents a case series describing three patients, from our institution, who developed positive anti‐HBc after IVIG administration. This passive antibody transfer created diagnostic uncertainty regarding prior hepatitis B virus (HBV) exposure. These cases demonstrate the challenges physicians face when distinguishing passive transfer of anti‐HBc from true previous HBV infection and highlight the potential consequences of misinterpretation of positive anti‐HBc testing in this clinical setting.
Conclusion
Recognition of passive anti‐HBc transfer after IVIG administration is important to avoid unnecessary diagnostic testing, antiviral therapy, and delays in starting immunosuppressive treatment. Physicians should consider the timing of IVIG administration when interpreting hepatitis B serologies. We propose obtaining baseline hepatitis B serologies before IVIG administration and we suggest building a best practice advisory into the electronic medical record that would serve as a reminder to providers ordering IVIG to obtain this baseline testing. Increased awareness of this phenomenon should improve accurate interpretation of positive anti‐HBc test results following IVIG and limit unnecessary interventions, delays in needed immunosuppressive therapies, and cost to both the patient and health care system.