Acute life‐threatening cardiovascular toxicity with umbilical cord blood infusion: The role of dextran

Umbilical cord blood (UCB) is being increasingly used for hematopoietic stem cell transplantation due to its immediate availability. Dimethylsulfoxide (DMSO) and dextran-40 are commonly used for processing and cryopreservation of UCB. Adverse UCB infusion-related events are usually mild. However, reports of severe life-threatening events are now emerging. DMSO has been proposed as a possible cause of infusion-related reactions. In this report, we draw attention to an acute near-fatal reaction with UCB infusions resulting in myocardial ischemia and acute renal failure. We propose that dextran-40 in UCB infusion products be considered as a potential causative agent contributing to this infusion-related reaction, based on reports of known adverse reactions to dextran-40 in non-transplant settings.