RhIG for the treatment of immune thrombocytopenia: consensus and controversy (CME)

Anti-D immune globulin (RhIG) is a front-line option in North America for the treatment of immune thrombocytopenia (ITP) in children and adults. Recently, addition of a Food and Drug Administration-mandated black box warning highlighted the risks of intravascular hemolysis, renal failure, and disseminated intravascular coagulation after anti-D infusion, prompting concern within the medical community regarding its use. A working group convened in response to this warning to prepare a consensus document regarding the safety of RhIG because there has been no increased incidence of adverse events since the initial discovery of these reactions many years ago. The efficacy of anti-D is well documented and only briefly reviewed. The estimated incidence and proposed mechanisms for the rare, major treatment-related complications are discussed, and signal detection data associated with heightened risk of acute hemolytic reactions are presented. The importance of considering host factors, given the rarity of severe reactions, is emphasized. Safety profiles of parallel treatment options are reviewed. The working group consensus is that RhIG has comparable safety and efficacy to other front-line agents for the treatment of children and adults with ITP. Safety may be further improved by careful patient selection.