Anti-HI can cause a severe delayed hemolytic transfusion reaction with hyperhemolysis in sickle cell disease patients

Hemolysis due to anti-IH in a patient with beta-thalassemia and Mycoplasma pneumoniae infection

Anti-IH is a common cold agglutinin that is typically clinically insignificant. We present a case that resulted in hemolysis. A 32-year-old male patient with transfusion-independent beta-thalassemia intermedia presented with symptomatic anemia. His blood sample typed as group B, D+ and demonstrated multiple alloantibodies and cold autoantibodies. He was transfused uneventfully, but re-presented 10 days later with recurrent, worsening anemia. At this time, transfusion of group O, phenotype-matched red blood cells (RBCs) resulted in an acute hemolytic reaction. While anemia was initially attributed to drug-mediated bone marrow toxicit y and subsequently to a delayed hemolytic reaction, further evaluation revealed Mycoplasma pneumoniae infection and a cold agglutinin (anti-IH specificity), indicating a likely autoimmune-mediated anemia due to an infectious etiology. Subsequent transfusion of 2 group B, phenotype-matched RBC units using a blood warmer was uneventful. Anti-IH is only rarely associated with hemolytic transfusion reactions, which may be exacerbated when transfusing group O RBC units to group B patients. M. pneumoniae infection likely led to cold agglutinin-mediated hemolysis of endogenous and transfused RBCs. The patient was successfully managed with intravenous immunoglobulin, steroids, rituximab, erythropoietin, hydroxyurea, and amoxicillin clavulanate/azithromycin. This case illustrates the importance of infectious disease evaluation in patients with unexplained anemia, the potential clinical significance of autoanti-IH, and the value of providing type-specific RBC units in these circumstances.

Eleven years of alloimmunization in 6496 patients with sickle cell disease in France who received transfusion

ABSTRACT

Red blood cell (RBC) transfusion is a major therapy for sickle cell disease (SCD). Patients are at risk of forming antibodies to RBC antigens, which can result in the impossibility to find compatible units and can cause hemolytic transfusion reactions. This retrospective study investigates the evolution of RBC consumption and the frequencies, specificities, and chronology of the appearance of antibodies in a population of patients consistently receiving RH (C, D, E, c, e) and K-matched RBC units (RBCus) from a predominantly European donor population. Over the 11-year period in the Paris area, 6496 patients received transfusion at least once for a total of 239 944 units. Antibodies were made by 1742 patients. The first antibodies of a patient were predictive of subsequent immunization. By the 17th RBCu transfused (by the 20th, excluding warm autoantibodies), 75% of the patients who would make antibodies had made their first. By the 16th, 90% who would make antibodies to a high frequency antigen had made their first antibody to these antigens. Females made their first antibodies slightly earlier than males. Patients who received multiple transfusions (>50 units) had a higher immunization prevalence than those who rarely received transfusion (<12 units) but fewer clinically significant antibodies. Patients with SCD and prophylactic RH-K matching not immunized by the 20th RBCu are likely to have a low alloimmunization risk (to antigens other than RH-K), that is, be low responders, especially relative to the most clinically significant antibodies. This number of 20 units is a point before which close monitoring of patients is most important but remains open to future adjustment.

Hyperhaemolysis caused by anti-HI antibodies in a patient with myelodysplastic syndrome following a first ever red cell transfusion

BACKGROUND

Hyperhaemolysis is a rare and life-threatening delayed haemolytic transfusion reaction characterised by complement-mediated destruction of both host and transfused red cells. It is well recognised as a complication of transfusion in patients with haemoglobinopathies and has occasionally been described in haematological malignancy and anaemia of chronic disease. Anti-HI antibodies are usually clinically insignificant but have rarely been associated with haemolytic transfusion reactions, including cases of hyperhaemolysis in sickle cell disease.

METHODS AND MATERIALS

Here, we describe a novel case of a patient with myelodysplastic syndrome developing hyperhaemolysis as a result of an anti-HI alloantibody following their first-ever transfusion. The patient required multiple lines of treatment, including erythropoietin, haematinic supplementation, corticosteroids, intravenous immunoglobulin and rituximab.

RESULTS

Following treatment, steady-state haemoglobin was achieved with quiescent haemolysis, and complement inhibition with eculizumab was considered but ultimately not required.

CONCLUSION

This is the first known report of hyperhaemolysis with an anti-HI antibody in a non-haemoglobinopathy patient. The treatment of hyperhaemolysis is evolving, and future commissioning needs to consider the role of complement inhibition in non-haemoglobinopathy patients.

Association of Veterinary Hematology and Transfusion Medicine (AVHTM) Transfusion Reaction Small Animal Consensus Statement (TRACS). Part 1: Definitions and clinical signs

OBJECTIVE

To use a systematic, evidence-based consensus process to develop definitions for transfusion reactions in dogs and cats.

DESIGN

Evidence evaluation of the literature was carried out for identified transfusion reaction types in dogs and cats. Reaction definitions were generated based on synthesis of human and veterinary literature. Consensus on the definitions was achieved through Delphi-style surveys. Draft recommendations were made available through industry specialty listservs and comments were incorporated.

RESULTS

Definitions with imputability criteria were developed for 14 types of transfusion reactions.

CONCLUSIONS

The evidence review and consensus process resulted in definitions that can be used to facilitate future veterinary transfusion reaction research.

Examining the Role of Complement in Predicting, Preventing, and Treating Hemolytic Transfusion Reactions

Red blood cell (RBC) transfusion is a critical component of optimal management for a broad range of conditions. Regardless of the indication, pretransfusion testing is required to appropriately match RBC donors and recipients to provide immunologically compatible blood. Although this approach is effective in the vast majority of situations, occasionally, patients will inadvertently receive an incompatible RBC transfusion, which can result in a hemolytic transfusion reaction (HTR). In addition, patients with life-threatening anemia and a complex alloantibody profile, which precludes rapid procurement of compatible RBCs, may also receive incompatible RBCs, placing them at risk for an HTR. Despite the rarity of these clinical situations, when incompatible blood transfusion results in an HTR, the consequences can be devastating. In this review, we will explore the challenges associated with actively preventing and treating acute HTRs following incompatible RBC transfusion. In doing so, we will focus primarily on the role of complement, not only as a key player in HTRs, but also as a potential target for the prevention and treatment of HTRs.

Challenges in preventing and treating hemolytic complications associated with red blood cell transfusion

Red blood cell (RBC) transfusion support represents a critical component of sickle cell disease (SCD) management. However, as with any therapeutic intervention, RBC transfusion is not without risk. Repeat exposure to allogeneic RBCs can result in the development of RBC alloantibodies that can make it difficult to find compatible RBCs for future transfusions and can directly increase the risk of developing acute or delayed hemolytic transfusion reactions, which can be further complicated by hyperhemolysis. Several prophylactic and treatment strategies have been employed in an effort to reduce or prevent hemolytic transfusion reactions. However, conflicting data exist regarding the efficacy of many of these approaches. We will explore the challenges associated with predicting, preventing and treating different types of hemolytic transfusion reactions in patients with SCD in addition to describing future strategies that may aid in the management of the complex transfusion requirements of SCD patients.

Immuno-hematological findings in Delayed Hemolytic Transfusion Reaction (DHTR)

Sickle cell disease (SCD) is the most prevalent genetic disorder in France. Many other countries are also affected. Transfusion is still a key treatment for patients suffering from this condition. As a result, SCD patients are much more exposed to transfusions and their risks than the general population. The most feared situation is delayed hemolytic transfusion reaction (DHTR). In certain situations, defined as hyperhemolysis, autologous red blood cells (RBCs) are also targeted and destroyed. This can put the patient in a life-threating situation. Further transfusions worsen the hemolysis. As DHTR will mimic a new or resistant vaso-occlusive crisis, it can be easily underdiagnosed. SCD patients are more likely to be alloimmunized than the general population, due to discrepancies between the recipient's and donor's RBCs phenotypes. Furthermore, they are often transfused in an inflammatory state, and they also frequently harbor partial antigens in the RH system. SCD patients are more prone to develop a new alloantibody than the general population. As a result, patients with DHTR often have complex mixtures of allo and autoantibodies; RH antibodies and those considered as irregular natural antibodies are frequent. Nevertheless, about a third of DHTRs are reported in patients with no previous history of immunization. In addition, a third of SCD patients will not develop an antibody after a DHTR. The evanescence of the antibodies is important. In several studies, DHTRs were reported only in patients who were occasionally transfused. Identifying patients at risk of developing a DHTR is key to managing them properly.

A Fatal Case of Immune Hyperhemolysis with Bone Marrow Necrosis in a Patient with Sickle Cell Disease

In patients with sickle cell disease, hyperhemolysis is a rare but life-threatening complication of transfusion. In this case report, we describe a 61 year-old woman with hemoglobin sickle cell (SC) disease and history of alloimmunization who developed hyperhemolysis associated with a transfusion. She was found to have a warm and a clinically-significant cold autoantibody. Severe anemia (Hb 2.7 g/dL) with reticulocytopenia and thrombocytopenia prompted a bone marrow biopsy, which demonstrated extensive bone marrow necrosis. Despite treatment, the bone marrow failure did not improve and the patient died on hospital day 38. This case illustrates the potential risks of transfusion in a patient with sickle cell disease, especially one with previous hemolytic reactions. While uncommon, hyperhemolysis can cause death, in this case by extensive bone marrow necrosis. In patients with sickle cell disease, judicious use of red cell transfusions with phenotypically-matched units can diminish, but never completely abrogate, the risks associated with transfusion.