Tauscher, Craig D.

Abstract Background: Little data exists on the incidence rate of transfusion reactions and red cell antibody formation following allogeneic (allo) hematopoietic progenitor cell transplant (HPCT) recipients. Study Design and Methods: Consecutive related and unrelated Allogeneic HPCTs from 2006 to 2013 were retrospectively reviewed regardless of graft source. Allo HPCT recipients were analyzed as a whole as well as divided into ABO compatibility groups of identical, minor mismatch, and major/bidirectional mismatch. Transfusions, transfusion reactions and antibodies were analyzed for the first year post-transplant while survival was recorded throughout the available follow-up period. Results: During the study period, 573 patients ranging in age from 0.6 to 72 years underwent first allo HPCT for various malignant and non-malignant etiologies: 278 acute leukemias, 89 lymphomas, 40 multiple myelomas, 134 other hematologic malignancies, 32 non-neoplastic etiologies. Of these, 52% underwent myeloablative conditioning and 48% reduced intensity conditioning. Transfusion reactions were reported in 93 of the 573 allo HPCT recipients. The incidence rate of transfusion reactions per 10,000 transfusion episodes was 45.54 in the ABO identical, 61.28 in the minor mismatch, and 29.95 in the major mismatch groups (p=0.04). The most common reaction type reported in all groups was allergic followed by febrile non-hemolytic, transfusion associated circulatory overload, and delayed hemolytic or serologic reactions. No acute hemolytic, transfusion related acute lung injury (TRALI), post transfusion purpura, transfusion associated graft-versus-host disease, or transfusion associated sepsis reactions were reported. A total of 43 unique patients(7.5%) developed new antibodies post-transplant: 16 allo HPCT recipients developed clinically significant antibodies, 17 developed clinically insignificant antibodies, and 17 developed auto antibodies post-transplant. Including those patients with pre-transplant antibodies the overall prevalence of red blood cell antibodies was 14.5%. See Table 1 for incidence rate for forming new rbc antibodies post-transplant. Table 1. New RBC Antibody Formation Incidence Rate Post-Transplant ABO Compatibility Group Clinically Significant Antibody Incidence /10,000 RBC Transfusions Clinically Insignificant Antibody Incidence/ 10,000 RBC Transfusions, Auto Antibody Incidence/10,000 RBC Transfusions Total Antibody Incidence/10,000 RBC Transfusions Identical 39.33 16.85 39.33 95.51 Minor Mismatch 35.87 57.39 43.04 136.30 Major Mismatch 8.34 16.67 8.34 33.35 A statistically significant difference (p=0.001) was seen in total antibody incidence when comparing the ABO compatibility groups. The most common, clinically significant allo antibodies formed were Anti-E, Anti-Jka, Anti-A1, Anti-K, Anti-D, and Anti-C. Survival of allo HPCT recipients as a whole was not statistically different for those who formed new rbc antibodies post-transplant following adjustment for ABO compatibility, age at transplant, diagnosis, graft source, and pre-transplant rbc infusions (p=0.068). Allo HPCT recipients that formed new rbc antibodies were not shown to have prolonged engraftment. Engraftment, neutrophils (ANC) and platelets (PLT), were not statistically different (p=0.34 ANC; p=0.20 PLT) when comparing all allo HPCT recipients to those who formed a new rbc antibody. Conclusion: Transfusion reaction and rbc antibody incidence rates were higher in the ABO minor mismatch when compared to the ABO identical and ABO major mismatch groups. The reaction etiology (predominantly antibody mediated) and the formation of new antibodies indicates a surprisingly active humoral immune system. The overall prevalence of antibody formation is likely affected by high exposure to transfusions. Development of a new rbc antibody did not affect engraftment or survival outcomes. Disclosures No relevant conflicts of interest to declare.

Almost 50% of trauma‐related fatalities within the first 24 hours of injury are related to hemorrhage. Improved survival in severely injured patients has been demonstrated when massive transfusion protocols are rapidly invoked as part of a therapeutic approach known as damage control resuscitation (DCR). DCR incorporates the early use of plasma to prevent or correct trauma‐induced coagulopathy. DCR often requires the transfusion of plasma before determination of the recipient's ABO group. Historically, group AB plasma has been considered the “universal donor” plasma product. At our facility, the number of AB plasma products produced on an annual basis was found to be inadequate to support the trauma service's DCR program. A joint decision was made by the transfusion medicine and trauma services to provide group A thawed plasma (TP) for in‐hospital and prehospital DCR protocols. A description of the implementation of group A TP into the DCR program is provided as well as outcome data pertaining to the use of TP in trauma patients.

BackgroundThe cold agglutinin (CAGG) titer is offered at our institution to aid in diagnosing cold agglutinin disease (CAD). Our goal was to create a seasonally adjusted reference range using prospective samples and compare it to a reference range generated retrospectively.Study Design and MethodsProspective CAGG titer testing was performed on healthy blood donors. Retrospective electronic analysis was performed on patients in two groups defined by current and historical testing methods. Blood donor testing was performed in January and July to determine if seasonal variation existed. Retrospective patients with conditions associated with CAD were excluded from analysis. Additional prospective CAGG testing using reference range program volunteers was performed to verify blood donor and patient result differences.ResultsTiters from the blood donor and patient cohorts had no age association (p > 0.44). Titers from those same cohorts did not show winter/summer variation (p > 0.11). No sex association was found with titer reference ranges in the blood donor and historical patient cohort. A sex association was found with titers in the current method patient cohort (male 64 to 512 and female ≤64; p < 0.0001). Blood donor CAGG titer lower 95% reference range was not more than 4 while historical and current patient cohorts ranges were not more than 32 and not more than 64, respectively. Reference range volunteers confirmed the narrow reference range in healthy individuals when compared to patients and blood donors.ConclusionProspective blood donor CAGG titers were lower than retrospective patient cohorts. This may be due to blood donors representing a healthier population than the patient cohorts.