Adverse events associated with infusion of stem cell products in pediatric blood and marrow transplant recipients

Background
Adverse events (AEs) associated with blood product transfusions have been extensively studied, whereas those associated with cellular therapy products (CTPs) seen in children undergoing hematopoietic stem cell transplantations are not commonly documented and analyzed.


Patients and Methods
Herein, we retrospectively studied pediatric patients below the age of 14 years for AEs within 48 h of CTP infusions while evaluating them in the context of pre-existing allergies, transplant-related parameters, and the outcome of the events. Data from 656 consecutive pediatric transplants at our institution from 2016 to 2020 was analyzed. Observed events were classified and graded as per CTC AE (Version 5.0) and consolidated into a single binary variable. The incidence of AEs recorded during the first 48 h of infusion was 4.9% (n = 32).


Results
Hypertension was the most common AE observed in 28 episodes, followed by hematuria (four episodes). Occurrence of AEs was found to be significantly associated with older age of the recipients (P = 0.048), hemoglobinopathies as a primary indication for transplant (P = 0.016), allogeneic graft type (P = 0.039), bone marrow as a source of the stem cells (P = 0.006), and documented substance allergies prior to infusion (P = 0.001). We did not find any association between children with AEs and the toxicity of dimethyl sulfoxide with the number of bags used for transfusion (single: 17 [56.7%] vs. multiple: 13 [43.3%], P value: NS).


Conclusion
In conclusion, our patients had low rates of AEs with CTPs. These AEs vary with allergenicity and need to be monitored with similar caution as regular blood products.