In pediatric patients with sick cell disease (SCD), red blood cell (RBC) transfusion during proinflammatory events was found to increase alloimmunization, which was not mitigated by hydroxyurea (HU), according to a recent study published in Blood.
RBC alloimmunization increases the risk of hemolytic transfusion reactions in patients with SCD and makes it difficult to find compatible blood for future transfusions. HU, a progressively utilized therapy for SCD prevention, triggers myelosuppression and diminishes inflammation. Researchers in the departments of hematology and pathology at St. Jude Children’s Research Hospital conducted a retrospective cohort study in pediatric patients with SCD “to explore the risk factors for alloimmunization, focusing on the roles of the recipients’ proinflammatory state, HU therapy, and Rh variants in alloimmunization.”
Of the 471 patients included in the study, the average age was 12.9 years and 99.2% of patients self-identified as Black. The most commonly observed hemoglobin (Hb) genotypes were Hb S (HbSS) and HbSβ0-thalassemia (81.5%). The overall alloimmunization rate was 11.7%. These patients formed 59 alloantibodies and 17 autoantibodies, with an alloimmunization rate of 0.36 alloantibodies per 100 units.
The investigators noted that alloimmunization of patients who received episodic transfusion was not reduced by HU therapy (P=.071), HU therapy duration (P=.056), or HU dose (P=.242). “The risk of alloimmunization was also higher for patients with HbSS and HbSβ0-thalassemia genotypes and those with a high transfusion burden,” they wrote.
A further analysis of 27 patients whose alloantibodies were formed with specificities showed 23.8% of units transfused during a proinflammatory event resulting in alloantibody formation compared with 2.8% of units transfused at a steady state, suggesting transfusion during proinflammatory events increased the risk for alloimmunization (P=.003).
“Judicious use of transfusion during proinflammatory events is critical for preventing alloimmunization,” the investigators concluded.
In pediatric patients with sick cell disease (SCD), red blood cell (RBC) transfusion during proinflammatory events was found to increase alloimmunization, which was not mitigated by hydroxyurea (HU), according to a recent study published in Blood.
RBC alloimmunization increases the risk of hemolytic transfusion reactions in patients with SCD and makes it difficult to find compatible blood for future transfusions. HU, a progressively utilized therapy for SCD prevention, triggers myelosuppression and diminishes inflammation. Researchers in the departments of hematology and pathology at St. Jude Children’s Research Hospital conducted a retrospective cohort study in pediatric patients with SCD “to explore the risk factors for alloimmunization, focusing on the roles of the recipients’ proinflammatory state, HU therapy, and Rh variants in alloimmunization.”
Of the 471 patients included in the study, the average age was 12.9 years and 99.2% of patients self-identified as Black. The most commonly observed hemoglobin (Hb) genotypes were Hb S (HbSS) and HbSβ0-thalassemia (81.5%). The overall alloimmunization rate was 11.7%. These patients formed 59 alloantibodies and 17 autoantibodies, with an alloimmunization rate of 0.36 alloantibodies per 100 units.
The investigators noted that alloimmunization of patients who received episodic transfusion was not reduced by HU therapy (P=.071), HU therapy duration (P=.056), or HU dose (P=.242). “The risk of alloimmunization was also higher for patients with HbSS and HbSβ0-thalassemia genotypes and those with a high transfusion burden,” they wrote.
A further analysis of 27 patients whose alloantibodies were formed with specificities showed 23.8% of units transfused during a proinflammatory event resulting in alloantibody formation compared with 2.8% of units transfused at a steady state, suggesting transfusion during proinflammatory events increased the risk for alloimmunization (P=.003).
“Judicious use of transfusion during proinflammatory events is critical for preventing alloimmunization,” the investigators concluded.
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