(P-TS-86) Recognition of hyperhemolysis syndrome and new anti-U antibody complicated by cold antibodies and vaso-occlusive crises

Hyperhemolysis syndrome (HHS) is an uncommon complication of sickle cell disease (SCD) with acute onset of anemia associated with destruction of both transfused and recipient red blood cells.

Study

Design/Methods:

An 18 year old African-American woman, with history of SCD was admitted for vaso-occlusive crisis and acute pancreatitis secondary to bilirubin gallstones. She received 2 units of crossmatch-compatible packed red blood cells (pRBCs) prophylactically prior to cholecystectomy (Day +0) and was discharged (Day+2).
She returned to the hospital (Day+8) with acute onset of back pain and fever, initially thought to be post-operative pain crisis. Identification of new hemolysis was initially obscured by hemolytic lab values unchanged from the prior admission (table 1). A unit of crossmatch-compatible pRBCs was transfused on Day+10. The patient’s hemoglobin dropped with a nadir of 4.2 g/dL, and she developed acute kidney injury (AKI). After identification of HHS, she received IVIG, IV steroids, and eculizumab. Her hemoglobin stabilized and AKI subsequently resolved.

Results/Findings:

Red cell antibody history prior to the inciting transfusion included nonspecific cold antibodies and nonspecific reactivity at AHG phase using manual tube testing with PEG enhancement. Antibody screen was negative via manual 1-hour saline tube testing.

Pretransfusion testing performed on Day+8 after re-admission showed near pan-reactivity by solid-phase RBC adherence testing. PEG-enhanced and 1-hour saline tube testing showed near pan-agglutination at immediate spin and AHG phase. The autocontrol was weakly positive. A direct antiglobulin test (DAT) was negative. At the time, these findings were attributed to a strong cold agglutinin. The sample was sent for reference lab alloadsorption studies. This workup returned after transfusion on Day+10 and revealed the presence of new anti-U and cold antibody specificity for anti-IH.

Conclusions:

Anti-IH is a complex antibody that is typically benign, however may rarely result in cold agglutinin syndrome and hemolytic transfusion reactions. In this case, its main significance was in obscuring recognition of the development of an antibody to a high prevalence antigen. A high rate of antibody formation in patients with SCD and hemolytic labs elevated by nature of the disease condition complicate rapid identification of new alloantibodies and transfusion reactions. This is especially so as DAT is often negative in HHS. A high index of suspicion is required for early identification of this uncommon transfusion reaction.