Hepatitis B screening in hematology patients receiving intravenous immunoglobulin.

Background: Transient positivity for hepatitis B core antibody (Anti‐HBc) following intravenous immunoglobulin (IVIG) and subcutaneous immunoglobulin exposure is a well‐described phenomenon. The aim of this study was to retrospectively review Hepatitis B viral screening practices in IVIG recipients in a hematology specific cohort at a single center. Methods: Electronic databases were analyzed to identify all hematology patients who received IVIG from September 2022 to March 2022 at a single Irish center (n = 43). The proportion of patients that had a baseline anti‐HBc tested prior to IVIG receipt was assessed as well as the proportion of patients that developed a transiently positive anti‐HBc following IVIG exposure. Data were also collected relating to signal cut‐off ratios in patients with detectable anti‐HBc post‐IVIG. Results: 58.1% of patients had at least one serological hepatitis B viral test sent prior to IVIG exposure. Anti‐HBc was the least common serological investigation performed prior to IVIG exposure (21% of recipients). A positive or equivocal "low level antibody" was identified in 15% of recipients and this was proven to be transient in all cases. Conclusion: The minority of hematology patients had a baseline anti‐HBc assessed prior to IVIG exposure. All patients in this study had the potential to require further immunosuppressive therapies, which could be limited by a misleading anti‐HBc result. We therefore advocate for baseline anti‐HBc testing to be performed prior to IVIG exposure in hematology patients and for cautious interpretation of anti‐HBc results taking into account signal cut‐off ratios post‐IVIG exposure. [ABSTRACT FROM AUTHOR]