Eculizumab for management of hyperhemolysis syndrome in pediatric patients with sickle cell disease: A single-center case series.

Chronic hemolytic anemia and vascular occlusion are hallmarks of sickle cell disease (SCD). Blood transfusions are critical for supportive and preventive management of SCD complications. Patients with SCD are at risk for hyperhemolysis syndrome (HHS), a subtype of delayed hemolytic transfusion reactions. HHS management includes intravenous immunoglobulin, corticosteroids, and avoidance of further transfusions. Not all patients respond to first-line agents. Eculizumab, which blocks terminal complement activation, has been proposed as second-line management of HHS. We describe two patients who received eculizumab for refractory HHS. In our experience, eculizumab is a safe and effective option for refractory pediatric HHS.

Utility of hemoglobin electrophoresis to distinguish between severe delayed hemolytic transfusion reaction versus hyperhemolysis syndrome.

Delayed hemolytic transfusion reaction (DHTR) and hyperhemolysis syndrome (HHS) are both complications of red blood cell transfusions in patients with sickle cell disease.Clinically, both present with hemolysis and can be difficult to differentiate. Hemoglobin electrophoresis may aid in the diagnosis. Herein we describe a case in which a patient with hemoglobin SC disease presented with features of severe hemolysis several days after initiation of red blood cell exchange. Increase in reticulocyte count and complete absence of hemoglobin A on electrophoresis during this event supported the diagnosis of severe DHTR, indicating a rapid and selective destruction of the transfused red blood cells. Ability to interpret the hemoglobin electrophoresis can help clinicians distinguish between these two severe transfusion complications in patients living with sickle cell disease. It is important to identify the presence or absence of concomitant HHS, as patients with HHS tend to have a worse prognosis and there is a higher rate of recurrence of HHS with subsequent transfusions. Accurate diagnosis can lead to prompt management and decrease morbidity and mortality.

Epidemiological and clinical features, therapeutic strategies and outcomes in patients with hyperhaemolysis: A systematic review.

Hyperhaemolysis syndrome (HHS), a severe form of delayed haemolytic transfusion reaction most commonly described in patients with sickle cell disease (SCD), involves destruction of both donor and recipient red blood cells (RBCs). As the epidemiology and underlying pathophysiology have yet to be definitively elucidated, recognition can be challenging. We systematically reviewed PubMed and EMBASE to identify all cases of post-transfusion hyperhaemolysis and characterized the epidemiological, clinical and immunohaematological characteristics and treatments of HHS. We identified 51 patients (33 females and 18 males), including 31 patients with SCD (HbSS, HbSC and HbS/ß-thalassaemia). The median haemoglobin nadir (3.9 g/dL) occurred a median of 10 days post-transfusion. 32.6% and 45.7% of patients had a negative indirect anti-globulin test and a negative direct anti-globulin test, respectively. The most common therapies included corticosteroids and intravenous immune globulin. 66.0% of patients received ≥1 supportive transfusion, which was associated with a longer median hospital stay/time to recovery (23 days vs. 15 days; p = 0.015) compared to no supportive transfusion. These findings illustrate that HHS that often results in marked anaemia 10 days post-transfusion is not restricted to patients with haemoglobinopathies, and additional transfused RBCs may be associated with a longer time-to-recovery.

A case of hyperhemolysis syndrome in sickle cell disease and concomitant COVID-19.

BACKGROUND: Hyperhemolysis syndrome (HHS) is an uncommon transfusion reaction described in several hematologic disorders, including sickle cell disease (SCD). HHS is characterized by a decline in hemoglobin (Hb) values below pre-transfusion levels following transfusion of red blood cells (RBCs), coupled with laboratory markers consistent with hemolysis. The proposed pathophysiologic mechanisms underlying HHS include increased phosphatidylserine expression, macrophage activation, and complement dysregulation. Many pathophysiologic mechanisms thought to contribute to HHS have been similarly described in cases of severe COVID-19. CASE REPORT: A 28-year-old male with a history of HbSS presented with shortness of breath, right-sided chest pain, and a two-day history of fever. Polymerase chain reaction (PCR) detected SARS-CoV-2 infection with the omicron variant. The patient required an RBC transfusion (pre-transfusion hemoglobin [Hb]5.8 g/dL) with an immediate post-transfusion Hb of 6.3 g/dL. However, Hb rapidly declined to 1.7 g/dL, and lactate dehydrogenase (LDH) rose to 8701 u/L. The absolute reticulocyte count of 538 × 109/L correspondingly fell to 29 × 109/L. Despite additional RBC transfusions and initiation of immunosuppressive therapy, he expired on Day 9(D9). CONCLUSION: Given the similarities in their proposed pathophysiology, patients with SCD and concomitant SARS-CoV-2 infection may be predisposed to developing HHS.

Tocilizumab in the management of posttransfusion hyperhemolysis syndrome in sickle cell disease: The experience so far.

BACKGROUND: Posttransfusion hyperhemolysis syndrome is a rare but life-threatening form of delayed hemolytic transfusion reaction with lysis of both transfused and autologous red cells, seen predominantly in patients with sickle cell disease. Macrophage activation is thought to play a major role in its pathophysiology. Standard treatment is with intravenous immunoglobulin and steroids but refractory cases pose a major clinical problem. Tocilizumab is a humanized monoclonal antibody against the IL-6 receptor that can inhibit IL-6 induced macrophage activation. METHODS AND MATERIALS: We describe the case of a 33-year-old woman with sickle cell anemia and posttransfusion hyper hemolysis syndrome refractory to standard therapy, treated with Tocilizumab. We also review all cases reported in the literature where Tocilizumab was used for posttransfusion hyperhemolysis. RESULTS: Treatment with Tocilizumab was well tolerated with no observed adverse events. There was no further drop in Hb after day 2 of treatment with subsequent continuous gradual improvement. Her bilirubin dropped significantly after the first dose and continued to improve, while ferritin and LDH reduced significantly after day 2 of treatment with Tocilizumab and continued to drop thereafter. Like in our case, all other cases in the literature where Tocilizumab was used for posttransfusion hyperhemolysis led to rapid clinical responses and no adverse events. DISCUSSION: Even though the number of cases of posttransfusion hyper hemolysis syndrome treated with Tocilizumab are few, they have all been associated with rapid clinical responses with no observed adverse events suggesting that the role of Tocilizumab in this context needs to be further explored.

Urgent use of voxelotor in sickle cell disease when immediate transfusion is not safe.

The use of blood transfusions to improve anemia resulting from sickle cell disease (SCD) is often limited by alloimmunization, which occurs due to exposure to incompatible antigen present on donor red blood cells (RBCs). This complication occasionally manifests as delayed hemolytic transfusion reactions (DHTRs) that cause hemolysis of the recipient's own RBCs and can lead to fatal anemia. In this case study, we report a patient with SCD who experienced a DHTR following chronic transfusion and was successfully treated with voxelotor, an orally administered sickle hemoglobin (HbS) polymerization inhibitor for the treatment of SCD. Laboratory tests following admission indicated pan-reactivity in antigens, and a rare donor registry was used to locate acceptable units. The patient experienced the DHTR 3 days after admission, which limited laboratory tests due to profound hemolysis. Alternative treatments were limited, and phenotypically matched units were incompatible, so voxelotor was selected as a last-resort treatment. Following initiation of voxelotor 1500 mg, the patient's hemoglobin levels returned to baseline (6 g/dl) within 10 days, with clinical improvements. This report provides evidence regarding the use of voxelotor in the treatment of profound anemia where other treatments could be unsafe or unavailable.

Recurrent hyperhemolytic transfusion reaction in myelodysplastic syndrome- A case based approach.

We present here a case report of a 27 year old female, with myelodysplatic syndrome suspected to have recurrent hyperhemolytic transfusion reactions (HHTR). Patient was transfusion dependent for ten years and was transfused with leukodepleted and irradiated Packed Red Blood Cells (PRBC). She presented with signs and symptoms of acute intravascular hemolysis, deranged coagulation profile with post transfusion Hb lower than baseline. Post transfusion workup was uneventful. She was managed conservatively with fluid support and methylprednisolone initially. After few uneventful transfusions, patient developed second episode of HHTR with compatible unit.Immunophenotype favored an inflammatory response possibly induced by monocytic lineage. As transfusion dependent, the patient required methylprednisolone as premedication and all subsequent transfusions were uneventful.

Etiopathological mechanisms and clinical characteristics of hyperhemolysis syndrome in Spanish patients with thalassemia.

Hyperhemolysis syndrome (HHS) is characterized by severe intravascular hemolysis with a decrease in the reticulocyte count, which is triggered and aggravated by transfusion and cannot be explained by standard immunohematological studies. A nationwide study was conducted in order to retrospectively identify thalassemia patients with HHS in Spain in order to assess pre-disposing mechanisms for this syndrome. For this, the expression of adhesion (CD49, CD36) and complement-related molecules (C3a, CD59) and the levels of reticulocyte apoptosis and macrophage activation were measured in 4 thalassemia patients with HHS, 14 patients without HHS, and 10 healthy subjects. Five of the six thalassemia patients had δß-thalassemia. The patients were not alloimmunized prior to the syndrome, which was developed after the first transfusion in all but one case. Patients with δß-thalassemia did not respond to corticoids or immunoglobulins; only splenectomy was successful. The expression of CD49 (α4ß1 integrin) was far higher in patients who had experienced HHS (85.07 ± 18.46 vs. 46.28 ± 24.31; p < 0.01), and the difference remained significant after correcting by the number of molecules analyzed (Bonferroni p < 0.05). In our population, δß-thalassemia was the most common hemoglobinopathy in patients with HHS. Furthermore, the risk to develop this syndrome may be associated with an increased expression of α4ß1 integrin.

What is the role of complement in bystander hemolysis? Old concept, new insights.

INTRODUCTION: Bystander hemolysis occurs when antigen-negative red blood cells (RBCs) are lysed by the complement system. Many clinical entities including passenger lymphocyte syndrome, hyperhemolysis following blood transfusion, and paroxysmal nocturnal hemoglobinuria are complicated by bystander hemolysis. AREAS COVERED: The review provides data about the role of the complement system in the pathogenesis of bystander hemolysis. Moreover, future perspectives on the understanding and management of this syndrome are described. EXPERT OPINION: Complement system can be activated via classical, alternative, and lectin pathways. Classical pathway activation is mediated by antigen-antibody (autoantibodies and alloantibodies against autologous RBCs, infectious agents) complexes. Alternative pathway initiation is triggered by heme, RBC microvesicles, and endothelial injury that is a result of intravascular hemolysis. Thus, C5b is formed, binds with C6-C9 compomers, and MAC (C5b-9) is formulated in bystander RBCs membranes, leading to cell lysis. Intravascular hemolysis, results in activation of the alternative pathway, establishing a vicious cycle between complement activation and bystander hemolysis. C5 inhibitors have been used effectively in patients with hyperhemolysis syndrome and other entities characterized by bystander hemolysis.

Delayed Hemolytic Transfusion Reaction With Hyperhemolysis Syndrome Due to Anti-M Alloantibody in Myelofibrosis: A Case Report.

Hyperhemolysis syndrome (HHS) and delayed hemolytic transfusion reaction (DHTR) commonly occur in patients with sickle cell disease (SCD) and thalassemia, due to the need for recurrent red blood cell (RBC) transfusion, but rarely in patients with myelofibrosis. HHS is a life-threatening condition that occurs with or without DHTR, in which both transfused and autologous RBCs are destroyed. It needs a high clinical suspicion for diagnosis, especially when there is a drop in hemoglobin level to the level of pretransfusion of RBCs, accompanied by hyperbilirubinemia and reticulocytopenia. The management of HHS includes avoiding RBC transfusion, supportive care, and immunomodulatory therapy. We present a case of HHS with DHTR in a patient with primary myelofibrosis who was treated successfully with steroids and splenectomy.

Acute Hyperhemolysis Syndrome in a Patient with Known Sickle Cell Anemia Refractory to Steroids and IVIG Treated with Tocilizumab and Erythropoietin: A Case Report and Review of Literature.

Patients with sickle cell anemia often receive multiple red blood cell (RBC) transfusions during their lifetime. Hyperhemolysis is a life-threatening phenomenon of accelerated hemolysis and worsening anemia that occurs when both transfused RBCs and autologous RBCs are destroyed. The level of hemoglobin post-transfusion is lower than pre-transfusion levels, and patients are usually hemodynamically unstable. Hyperhemolysis must be differentiated from a delayed hemolytic transfusion reaction during which destruction of transfused RBC is the cause of anemia. Hyperhemolysis syndrome can be differentiated into acute (within seven days) and chronic forms (after seven days) post-transfusion. The authors present a case of acute hyperhemolysis syndrome in a patient with sickle cell anemia refractory to steroids and IVIG, which are the treatment of choice. The patient was treated with tocilizumab, combined with supportive measures of erythropoietin, iron, vitamin B12, and folate.

An Unusual Case of Delayed Hemolytic Transfusion Reaction With Hyperhemolysis Syndrome Due to Anti-Jkb and Anti-Fya Alloantibodies.

Delayed hemolytic transfusion reaction (DHTR) is a complication appearing a few days to weeks due to alloimmunization following packed red blood cells (RBCs) transfusion, a pregnancy, or transplantation. Hyperhemolysis syndrome (HS) is a severe form of DHTR defined by a drop of hemoglobin to a level lower than before the transfusion, reflecting a destruction of the patient's own RBCs not presenting the targeted antigen as well as the transfused RBCs. Usually seen in sickle cell disease (SCD) patients, HS remains very rare in patients without a hematologic disorder. We report the case of an 82-year-old Caucasian woman who presented with a DHTR with HS after being transfused packed RBC twice in the context of rectal bleeding. The patient was not known for any hemoglobinopathy and did not have a history of massive transfusions nor multiple pregnancies putting her at risk of alloimmunization. Our patient developed anti-C, anti-Fya and anti-Jkb antibodies, known to be harmful antibodies. First line of treatment after avoidance of further transfusions is intravenous immunoglobulins for 3 to 5 days and high-dose corticosteroids. Exceptional in the non-SCD population, this complication should be recalled by clinicians as it can be fatal if not treated appropriately. We performed a review of the literature using the words "delayed hemolytic transfusion reaction" and "hyperhemolysis syndrome" for similar cases. Finally, we describe how to diagnose, manage, and prevent this potentially fatal complication, which is still underrecognized even within the SCD population.

Recurrent Hyperhemolysis Syndrome in Sickle Cell Disease.

Sickle cell disease is a disorder of hemoglobin. The abnormal hemoglobin S disrupts blood flow, thereby resulting in acute painful sickle cell crisis. These episodes frequently prompt packed red blood cell transfusions to replace a patient's functional hemoglobin stores. Production of alloantibodies and autoantibodies to these transfusions can result in a rare, but serious, complication known as hyperhemolysis syndrome. Hyperhemolysis syndrome presents several challenges in regard to its acute management and the consequent difficulties in finding future compatible blood products. We report a case of recurrent hyperhemolysis syndrome. Both episodes occurred following orthopedic procedures, and the recurrent episode proved refractory to multiple treatments.

Eculizumab as a Treatment for Hyper-Haemolytic and Aplastic Crisis in Sickle Cell Disease.

BACKGROUND: Patients with sickle cell disease can experience various crises including sequestration crisis, haemolytic crisis and aplastic crisis. Due to alloantibody formation, transfusion alloantibodies can cause a haemolytic crisis. Treatment involves avoiding packed red blood cell transfusions, as well as intravenous immunoglobulin, steroids and eculizumab to decrease the chances of haemolysis. CASE DESCRIPTION: We report the case of a 42-year-old man who was found to have worsening anaemia after packed red blood cell transfusion with evidence suggestive of haemolytic crisis. Due to reticulocytopenia, aplastic crisis was also suspected and later confirmed via parvovirus IgG and IgM titres. The patient did not improve with steroid and intravenous immunoglobulin therapy and was treated with eculizumab as a salvage therapy. CONCLUSION: Concurrent hyper-haemolytic crisis and aplastic crisis should be suspected in patients with features of haemolysis and reticulocytopenia. Prompt recognition and treatment with eculizumab are paramount in those who fail steroid and intravenous immunoglobulin treatment. LEARNING POINTS: Treatment of hyper-haemolytic and aplastic crisis in sickle cell disease with eculizumab offers therapeutic benefit.A high index of suspicion for hyper-haemolytic crisis and aplastic crisis should be maintained in those with haemolytic features as well as reticulocytopenia in the setting of sickle cell disease.

Post-transfusion hyperhemolysis syndrome in a patient with beta thalassemia major.

Hyperhemolysis syndrome (HS) is characterized by the occurrence of severe anemia with post-transfusion hemoglobin and hematocrit levels being markedly lower than those present prior to transfusion. A high index of suspicion of HS in a multi-transfused thalassemia patient allows prompt institution of therapy resulting in improved survival outcome.

Hyperhemolysis in the Setting of Mixed-Autoimmune Hemolytic Anemia: A Rare Complication of COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel human pathogen known for its predilection on the respiratory system. Herein, we present a unique case in which a patient developed hyperhemolysis in the setting of mixed autoimmune hemolytic anemia (AIHA) secondary to SARS-CoV-2. A 33-years-old male with a past medical history of resolved immune thrombocytopenic purpura (ITP) presented to the hospital with symptoms of jaundice after being infected with SARS-CoV-2. On admission, his Hgb was 12.5 g/dL. Lab results showed indirect bilirubin of 13 mg/dL, LDH at 759 U/L, haptoglobin <10, and the percent reticulocyte count was 2.33%. A direct antiglobulin test (DAT) was also positive for C3, IgG, anti-E, in addition to both warm and cold autoantibodies. PCR was positive for COVID-19. Within two days of admission, his Hgb dropped to 5.9 g/dL. A total of seven units of packed red blood cell (pRBC) was required to achieve a Hgb of 6 g/dL in 48 hours. Patients with preexisting hematological abnormalities have a propensity to develop AIHA in the setting of the virus. The majority of the cases described in the literature were associated with warm AIHA. Our patient tested positive for both warm and cold antibodies, which may partially explain the mechanism behind hyperhemolysis in our patient.

Hyperhemolysis Syndrome in a Patient With Sickle Cell Disease and Acute Chest Syndrome.

Sickle cell anemia patients often present to the hospital with acute vaso-occlusive pain crisis. Symptoms can include, but are not limited to, chest pain, abdominal pain, and musculoskeletal pain. These symptoms are brought about due to the pathology of the disease. Abnormal hemoglobin S causes red blood cells to band together, otherwise known as "sickling." These patients also often present with very low hemoglobin levels on initial evaluation. In most cases, packed red blood cell transfusions are needed in order to replenish these patient's functional hemoglobin supply. Unfortunately, transfusing sickle cell patients can lead to an unwanted consequence, that of hyperhemolysis syndrome, in which blood transfusions prompt further hemolysis of the already sickled red blood cells. When this complication arises, caution must be exercised in deciding the next steps of treatment.

Management of cesarean delivery in a parturient with sickle cell disease.

Chronic hemolysis and intermittent vaso-occlusion in sickle cell disease can lead to recurrent blood transfusions with related complications such as antibody formation and rarely, life-threatening reactions. We report a case of a parturient who presented with complications of sickle cell disease and who later had fetal compromise that required an emergent cesarean delivery. Complex management decisions were made, aided by technologies such as rotational thromboelastometry, quantitative blood loss analysis and cell salvage.

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.

Hyperhemolysis in Patients With Hemoglobinopathies: A Single-Center Experience and Review of the Literature.

Hyperhemolysis is a severe and potentially life-threatening complication of transfusion described in numerous case reports and gaining recognition since 2009 via the UK Serious Hazards of Transfusion scheme. Although it is predominantly seen in patients with sickle cell disease, there are several reports of this complication in patients with other hemoglobinopathies as well as patients with a range of other hematologic diagnoses who have blood transfusions as part of their management. Our understanding of the underlying pathophysiology of this subtype of delayed transfusion reaction has increased over the last few years; however, there are still questions, which remain unanswered. In our center alone, we have encountered 9 cases in the last 5 years both in the adult and pediatric population. Here we discuss our experience in the diagnosis and management of this complication, and review other cases reported in the literature and the various existing theories behind the pathophysiology of this process. We also discuss the role of genotyping and using DNA technology to aid selection of the most appropriate blood for this patient group. With an increased awareness of hyperhemolysis, it would be advantageous to finally develop international registries to determine the true incidence of hyperhemolysis, better understand the pathophysiology, identify markers to predict which patients are at risk, and inform management guidelines.