Transfusion Reactions in Sickle Cell Disease (SCD) Patients Receiving Multiple Blood Transfusions.
Authors: Sakhalkar Vishwas S. , Veillon Diana M. , Cotelingam James D. , Hawthorne Linda M. , Caldito Gloria C. , McCaskill Deborah M. 
Published: April 2020

Abstract
Aim: To study transfusion reactions in our SCD patients before and after instituting the practice of transfusing C, E, K blood type negative (CEKneg) packed red blood cell (pRBC) units.
Material and Methods: We retrospectively reviewed blood bank records of all SCD patients transfused pRBCs since 1990. Statistical analysis was performed using the Chi square test and Fischer’s exact test.
Results: During 1990–2004, 500 SCD patients received pRBCs in our medical center. Of these, 387 received pRBC units crossmatched only for ABO and Rh blood types and suffered 37 transfusion reactions.
Table I: General data of various patient groups Major patient groups Number of patients Median age in yrs # of pRBCs Tx Total (%) Sex (m/f) (range) Total units Median (range) Grand total of all patients 500 240/260 22 (0.7–79) 16617 14 (1–524) CEK (&ABO) matched transfusion patients 113 62/51 8 (0.5–35) 2354 10 (1–143) Regular (only ABORh) matched Tx patients 387 (100) 178/209 26 (0.7–79) 14263 18 (1–524) AlloAB forming patients 121 (31.3) 56/65 29 (5–70) 7338 26 (1–500) Non-alloAB forming pts 266 (68.7) 122/144 25 (0.7–79) 6925 12 (1–524) Table 2: Transfusion reactions in various patient groups Major patient groups Total # of pts Total # of pRBCs Transfusion reactions (% of pts) [Incidence/1000 Tx] Total Febrile Allergic dHTR CEK matched pts 113 2354 0 0 0 0 Regular (ABORh) Tx pts 387 14263 37 (10%)[2.594] 10 23 (6%)[1.61] 4 (1%)[0.28] AlloAB forming pts 121 7338 23 (19%)[3.134] 4 (3%)[0.55] 15 (12%)[2.04] 4 (3%)[0.55] Non-alloAB forming pts 266 6925 14 (5%)[2.0] 6(2%)[0.87] 8 (3%)[1.16] 0 P value (alloAB vs non-alloAB) # of pts 0.25 0.684 0.266 - P value (alloAB vs non-alloAB) # of Tx &lt;0.001 0.809 0.002 -
121 developed alloantibodies (alloABs). 113 patients always received CEKneg pRBCs (from 1997). The technologist required 30 more minutes and $153 extra in reagent costs for this extended CEK match. Most Rh negative pRBC units were also CEKneg. 90% of our donors are Caucasian.
Discussion: ’Non-alloAB forming’ patients who received ABORh matched transfusions were 4 times less likely (and twice less likely when number of transfusions was considered) to develop allergic transfusion reaction (p=0.002), compared with ’alloAB forming’ counterparts. Similar finding is seen in patients receiving CEK matched pRBCs. It would be interesting to know if ’slow/rapid/non alloAB producer patients had any genetic predisposition accounting for early/slow/non-development of ABs and transfusion reactions or if alloAB formation transforms the immune system to a hyper-reactive state leading to autoAB formation/allergic reaction.
Conclusions: This study showed that utilizing extended antigen (C, E, K) matching for pRBC transfusion ↓↓ alloAB(p&lt;0.01) and autoAB(p=0.005) formation in our SCD patients and eliminated transfusion reactions. Universal availability of leukopoor pRBCs may have eliminated febrile reactions. AlloAB forming patients were more prone to develop allergic transfusion reaction (p=0.002). AutoAB formation was more common in patients with alloABs and did not cause complications. dHTRs were rare and mild. CEK matching made it easier to find and transfuse blood due to less formation of ABs and reactions. However, it resulted in marked overuse of Rh negative pRBCs, extra cost and additional effort to find CEKneg pRBCs for every transfusion.