Continuous blood exchange in rats as a novel approach for experimental investigation.

Blood exchange therapy, specifically Whole blood exchange (WBE), is increasingly being utilized in clinical settings to effectively treat a range of diseases. Consequently, there is an urgent requirement to establish convenient and clinically applicable animal models that can facilitate the exploration of blood exchange therapy mechanisms. Our study conducted continuous WBE in rats through femoral and tail vein catheterization using dual-directional syringe pumps. To demonstrate the applicability of continuous WBE, drug-induced hemolytic anemia (DIHA) was induced through phenylhydrazine hydrochloride (PHZ) injection. Notability, the rats of DIHA + WBE group all survived and recovered within the subsequent period. After the implementation of continuous WBE therapy day (Day 1), the DIHA + WBE group exhibited a statistically significant increase in red blood cells (RBC) (P = 0.0343) and hemoglobin (HGB) levels (P = 0.0090) compared to DIHA group. The rats in the DIHA + WBE group exhibited a faster recovery rate compared to the DIHA group, indicating the successful establishment of a continuous blood exchange protocol. This experimental approach demonstrates not just promising efficacy in the treatment of DIHA and offers a valuable tool for investigating the underlying mechanisms of blood exchange. Furthermore, it has a great potential to the advancement of biomedical research such as drug delivery exploration.

Hemolytic anemia associated with intravenous immunoglobulin in Kawasaki disease.

BACKGROUND: The administration of high-dose intravenous immunoglobulin (IVIG) is a standard treatment for the management of Kawasaki disease (KD). IVIG is known to be a highly effective and safe treatment. CASE PRESENTATION: We report the development of hemolytic anemia in seven children receiving repeated doses of IVIG. The children were aged 3-44 months and included 4 girls and 3 boys. All children received 10% IVIG and a second course of immunoglobulin because they did not respond to the first course of immunoglobulin. Two received high-dose aspirin (50 mg/kg), and five received low-dose aspirin (5 mg/kg). Two patients required additional methylprednisolone pulse therapy (30 mg/kg) after the second dose of immunoglobulin, and three patients received oral prednisolone therapy for defervescence. Three patients showed coronary artery dilation during hospitalization and normalized within two months. Pretreatment hemoglobin averaged 11.3-14.2 g/dL, and post-hemolytic anemia hemoglobin ranged from 7.4 to 9.6 g/dL, with a difference of 1.7-6.8 g/dL. Reticulocytes were increased to 3.3-13.2%. Peripheral blood smears showed normochromic normocytic anemia, and anisopoikilocytosis. All children were positive for warm-type antibodies with IgG+, C3d- in direct antiglobulin test, and the blood group was A + in five and B + in two. None of the patients received immunomodulatory therapy or red blood cell transfusions. They were followed for a year and all recovered. CONCLUSION: Especially, in non-O blood group KD patients who are refractory to initial IVIG and require a second dose of IVIG or 10% formulation the possibility of immune hemolytic anemia should be carefully considered, and close follow-up should be maintained after therapy.

[Advances in pathophysiology, diagnosis and treatment of adult severe-associated thrombotic microangiopathy].

Thrombotic microangiopathy (TMA) is a group of highly heterogeneous, acute and severe clinicopathological syndromes, characterized by microangiopathic hemolytic anemia (MAHA), thrombocytopenia and ischemic injury of end organs. TMA has the characteristics of dangerous condition, multiple organ involvement and high mortality. Patients with severe TMA need to be admitted to intensive care unit (ICU) for organ function support therapy. Early and rapid evaluation, differential diagnosis, and timely and effective treatment are the key to improve the prognosis of TMA patients. Here, we review the pathophysiological changes, diagnosis differential diagnosis, and treatment of the severe TMA in adult.

A 71-year-old male with a life-threatening recurrence of hemolytic anemia, thrombocytopenia, and acute kidney injury after pembrolizumab therapy: a case report.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment. However, their use has been restricted in patients with preexisting autoimmune diseases due to concerns about increased risk of immune-related adverse events (irAEs). CASE PRESENTATION: We present a case of a patient with stage IV lung adenocarcinoma and a history of complement-mediated autoimmune hemolytic anemia in remission. After receiving a single dose of pembrolizumab, the patient experienced life-threatening recurrent hemolytic anemia, de novo thrombocytopenia, diarrhea, myocarditis, and acute kidney injury. Laboratory tests confirmed the diagnosis of Evan's syndrome, with positive PAIgG and direct antiglobulin test. Treatment with intravenous methylprednisolone at a dose of 2 mg/kg resulted in a favorable response, with resolution of symptoms and rapid recovery of kidney function. The probable cause of pre-renal hypoperfusion (evidenced by a BUN-to-creatinine ratio of 48.1) leading to acute tubular injury was attributed to pembrolizumab-induced diarrhea. CONCLUSIONS: This case illustrates a life-threatening recurrence of complement-mediated autoimmune hemolytic anemia induced by ICIs. Clinicians should carefully consider the expected efficacy and potential toxicity before initiating ICIs therapy in patients with preexisting autoimmune diseases. Additionally, the occurrence of acute kidney injury during ICIs therapy adds complexity and requires careful differential diagnosis.

Why has plasma exchange failed in TRACK syndrome? Lessons from a new variant of the atypical hemolytic uremic syndrome.

Atypical hemolytic uremic syndrome (aHUS) is a rare and life-threatening form of thrombotic microangiopathy, associated with high mortality and morbidity. Most cases present with hemolytic anemia, thrombocytopenia, and renal insufficiency. However, it can have unusual multiple end-organ injuries including extrarenal organ and system involvements such as neurologic, cardiac, gastrointestinal, and respiratory systems. We describe a 4-year-old girl who developed aHUS due to the TSEN2 mutation and had cardiac involvement. She did not benefit from plasma exchange, as stated in previous cases. It should be kept in mind that therapeutic plasma exchange may not be beneficial in some cases of aHUS, especially due to genetic mutations.

Gastrointestinal involvement of passenger lymphocyte syndrome followed by minor ABO-incompatible renal transplantation: A case report.

BACKGROUND: People with group O blood are considered universal organ donors compatible with any other blood group. However, in the case of minor ABO-incompatible transplantation, immune-mediated hemolysis may occur due to concomitant transfer of donor B lymphocytes together with the allograft. These passenger lymphocytes can produce antibodies in the recipients erythrocytes, causing hemolytic anemia known as passenger lymphocyte syndrome (PLS). METHODS: A retrospective chart review was performed. RESULTS: A 6-year-old boy (A+) underwent transplantation of a kidney from his father (O+). On postoperative day (POD) 6, the patient developed fever with no explainable causes. On POD 11, he presented with abdominal pain, hematochezia, and severe diarrhea, with sudden hemolytic anemia. Since then, GI symptoms have continued. On POD 20, direct antiglobulin test (DAT) was positive, and the anti-A IgM/G titer was 2/32. The results of the anti-A antibody elution test were strongly positive (3+). These findings highly suggested PLS. On the same day, the GI symptoms suddenly worsened, and laboratory findings showed hemolysis and thrombocytopenia with disseminated intravascular coagulation (DIC). Abdominal computed tomography (CT) scans suggested ischemic colitis of venous origin, and the patient underwent segmental colectomy with ileostomy formation on POD 23. To remove the anti-A antibodies, the patient underwent therapeutic plasma exchange (TPE) five times until the DAT and anti-A elution test were negative. CONCLUSIONS: We report a case of gastrointestinal involvement of PLS that occurred after minor ABO-incompatible kidney transplantation. This is the first report of ischemic colitis as an atypical manifestation of PLS.

Acute hemolytic anemia after hematopoietic stem cell transplantation: An unusual invader.

69-year-old man with a history of diffuse large B-cell lymphoma (DLBCL) presented with severe acute hemolytic anemia 27 months after an autologous hematopoietic stem cell transplantation. Bone marrow aspirate revealed intracellular micro-organisms (arrows) located within the cytoplasm of red blood cells confirming the diagnosis of severe babesiosis.

[Hemolytic anemia in emergency and intensive care medicine]. / Hämolytische Anämien in der Notfall- und Intensivmedizin.

Hemolytic anemia (HA) is caused by premature destruction or degradation of red blood cells (RBC). Low hemoglobin, suppressed haptoglobin, reticulocytosis as well as an elevation of lactate dehydrogenase and bilirubin are common laboratory findings in HA. Intracorpuscular HA due to defects of the RBC themselves are distinguished from extracorpuscular HA due to external factors. Severity of symptoms such as fatigue and dyspnea depend on the degree of anemia. For optimal treatment of HA, a detailed evaluation of the patient history (including hereditary RBC defects, B symptoms and travel history) is necessary. Additional diagnostics (hematological diagnostics, infectious disease diagnostics, immunological diagnostics, computed tomography [CT] scan) should be performed according to the patient's individual requirements. Treatment of HA depends on the etiology. If HA is immune-mediated, immunosuppressive therapy is indicated, whereas HA due to infections usually improves after adequate anti-infective therapy. Anti-infective therapy should also be considered in patients with sickle cell disease who present with severe HA. In general, HA can be treated effectively in most cases.

Semi-selective plasma filtration applied to the treatment of acquired thrombotic thrombocytopenic purpura following bnt162b2 administration.

Following the widespread use of anti SARS-CoV-2 vaccines, there have been reports of thrombocytopenia developing after the administration of different types of vaccine. We report a case of a 63-year-old male who developed neurological symptoms after receiving the second dose of the bnt162b2 vaccine. Blood tests performed upon admission to the Emergency Department revealed severe thrombocytopenia and microangiopathic hemolytic anemia. ADAMTS13 activity was undetectable and antibody titer was high. Due to the rapid neurological deterioration, steroid therapy with prednisone was started at an initial dose of 1 mg/kg/day. Rituximab therapy was started to prevent the formation of new antibodies. Given the slow response to this therapy, we added Caplacizumab, (a monoclonal antibody anti-Von Willebrand factor) in order to inhibit platelet hyperaggregation, combined with standard plasma exchange. The patient experienced repeated episodes of intolerance to fresh frozen plasma (FFP). Switching from plasma exchange to plasma filtration, remission was attained in this unusual case of vaccine-related thrombocytopenia with microangiopathic hemolytic anemia.

A thorny matter: Spur cell anemia.

Spur cell anemia (SCA) is an acquired form of non-autoimmune hemolytic anemia that occurs in advanced liver disease. It is characterized by the presence of acanthocytes or spur cells, spiculated erythrocytes whose shortened life span causes anemia that is unresponsive to transfusion. SCA has been regarded as a rare condition with an ominous prognosis for which the only known cure is liver transplantation, but recent prospective studies have demonstrated the existence of a milder form of SCA in which there are smaller numbers of acanthocytes, but which is nevertheless associated with hemolysis and poor outcomes. This form of SCA appears to be considerably more common than the severe classical variant. The conventional understanding of the pathogenesis of SCA is that abnormalities of lipid metabolism are the primary event driving the formation of spur cells. However, the studies that underpin this theory are based on small numbers of patients with heterogeneous clinical features and inconsistent use of nomenclature for dysmorphic red blood cells. In this review, we discuss the evolution of the current understanding of SCA and therapeutic strategies that have been employed based on this understanding. Our goal is to raise awareness of this understudied condition that has significant implications for patient outcomes. Furthermore, we highlight the need for rigorous, contemporary research into the underlying cause or causes of SCA in order to develop an effective therapy for this disorder.

Renal Thrombotic Microangiopathy: A Review.

Thrombotic microangiopathy (TMA), a pathological lesion observed in a wide spectrum of diseases, is triggered by endothelial injury and/or dysfunction. Although TMA lesions are often accompanied by clinical features of microangiopathic hemolytic anemia, thrombocytopenia, and ischemic end-organ injury, renal-limited forms of TMA are not infrequently encountered in clinical practice. The presence of renal-limited manifestations can be diagnostically challenging, often delaying the initiation of targeted therapy. Prompt investigation and empirical treatment of TMA is warranted to reduce associated morbidity and mortality. Major advances have been made with respect to the pathophysiology of primary TMA entities, with the subsequent development of novel diagnostic tools and lifesaving therapies for diseases like thrombotic thrombocytopenic purpura and complement-mediated TMA. This article will review the clinical presentation and pathologic hallmarks of TMA involving the kidney, and the disease-specific mechanisms that contribute to the endothelial injury that characterizes TMA lesions. Diagnostic approach and both empirical and disease-specific treatment strategies will be discussed, along with the potential role for emerging targeted disease-specific therapies.

Advances in pathophysiology, diagnosis and treatment of adult severe-associated thrombotic microangiopathy / 中华危重病急救医学

Thrombotic microangiopathy (TMA) is a group of highly heterogeneous, acute and severe clinicopathological syndromes, characterized by microangiopathic hemolytic anemia (MAHA), thrombocytopenia and ischemic injury of end organs. TMA has the characteristics of dangerous condition, multiple organ involvement and high mortality. Patients with severe TMA need to be admitted to intensive care unit (ICU) for organ function support therapy. Early and rapid evaluation, differential diagnosis, and timely and effective treatment are the key to improve the prognosis of TMA patients. Here, we review the pathophysiological changes, diagnosis differential diagnosis, and treatment of the severe TMA in adult.

Therapeutic plasma exchange in gastric signet ring cell carcinoma presenting as microangiopathic hemolytic anemia: A rare case report.

Microangiopathic hemolytic anemia (MAHA) defines a group of disorders characterized by the formation of microthrombi in capillaries and arterioles and the fragmentation of erythrocytes that pass through. Cancer-related MAHA is a rare but serious condition that is encountered in patients diagnosed with a malignancy. This clinical picture is thought to be linked to certain tumor characteristics; particularly, adenocarcinoma histology, vascular invasion, and bone marrow infiltration. MAHA is most commonly associated with tumors of gastric, prostate, and breast origin. The optimal treatment is not clear; however, there is evidence for the importance of promptly starting an effective antineoplastic regimen and it was also reported that administering therapeutic plasma exchange (TPE) therapy for immunocomplex removal could be beneficial for patients with symptoms of bleeding and thrombosis. Here, we present a case that presented a picture of MAHA secondary to gastric signet-ring cell adenocarcinoma (SRCC). The clinical picture was initially evaluated as thrombotic thrombocytopenic purpura and the patient benefited significantly from the TPE treatment administered before the adenocarcinoma diagnosis was confirmed. In this period, epistaxis stopped, platelet count increased from 25 × 109 /L to 162 × 109 /L, fragmented erythrocyte rate in the peripheral smear decreased by more than 75% and other laboratory findings of hemolysis (LDH, bilirubin, etc.) significantly improved.

Thrombotic Thrombocytopenic Purpura Triggered by Acute Myeloid Leukemia: A Case Report.

BACKGROUND Acute myeloid leukemia (AML) is a myeloid progenitor malignancy characterized by clonal expansion of immature blasts. Complications of AML can result from disease-related or treatment-related complications and commonly include bleeding and disseminated intravascular coagulation. Thrombotic thrombocytopenic purpura (TTP) is a microangiopathy syndrome characterized by a mechanical hemolytic anemia and a consumptive thrombocytopenia resulting in end-organ damage from thrombotic occlusion of small vessels. CASE REPORT We describe a case of TTP at our institution that developed after diagnosis of AML, an exceedingly rare phenomenon with only one such documented case in the current literature. We were advised to see this patient after development of renal failure and encephalopathy. Suspicion for TTP was initially low, as our patient had a low pre-test probability of TTP by the PLASMIC score. Our patient was treated for disseminated intravascular coagulopathy, without response. Plasma exchange pheresis (PLEX) was eventually begun 3 days after presentation upon result of ADAMTS13 activity at 10%, with presence of inhibitor. ADAMTS13 activity levels were used to guide continuation of PLEX, given our patient's persistent pancytopenia. CONCLUSIONS Our case demonstrates the challenges of identifying and managing TTP in patients with concomitant hematologic malignancies. ADAMTS13 activity levels should be collected in patients presenting with evidence of hemolytic anemia, even if the pre-test probability of TTP is low.

Methemoglobinemia and Delayed Encephalopathy After 5-Bromo-2-Nitropyridine Poisoning: A Rare Case Report.

5-bromo-2-nitropyridine, an intermediate in the synthesis of pharmaceutical and pesticide products, is toxic to the human body. However, 5-bromo-2-nitropyridine poisoning has not been previously reported. Here, we report the case of a 40-year-old man who suffered skin and respiratory tract exposure to leaked 5-Bromo-2-nitropyridine at work. After exposure, the patient rapidly developed dizziness, fatigue, nausea, vomiting, chest distress, diffuse cyanosis, and coma. Methemoglobinemia, hemolytic anemia, rhabdomyolysis, and acute renal failure were observed after admission. He improved markedly after treatment, but delayed encephalopathy was confirmed 82 days after the exposure. This case highlights that 5-bromo-2-nitropyridine can be absorbed through the skin and respiratory tract, resulting in methemoglobinemia and delayed encephalopathy.

Claves diagnósticas en el síndrome hemolítico urémico atípico: apropósito de un caso / Diagnostic clues in atypical hemolytic uremic syndrome: a case report

El síndrome hemolítico urémico atípico (SHUa) es una entidad clínica caracterizada por anemia hemolítica no inmune, trombopenia y fallo renal, en la que las lesiones están mediadas por un proceso de microangiopatía trombótica (MAT) sistémica. Es una patología rara y cuyo origen es una desregulación del sistema del complemento debido a mutaciones en genes del mismo que llevan a una activación incontrolada de C5 y la formación del complejo de ataque de membrana. Su correcto diagnóstico permite prescribir el tratamiento basado en Eculizumab, inhibidor de C5.Se presenta el caso clínico de una paciente gestante con SHUa, con el objetivo de destacar la importancia del diagnóstico diferencial precoz para el establecimiento temprano de un tratamiento efectivo de esta patología. Se actualiza la fisiopatología, diagnóstico y estudio genético, así como el manejo terapéutico del SHUa. (AU)

How to approach haemolysis: Haemolytic anaemia for the general physician.

Haemolytic anaemia can seem like a complicated topic. The constellation of reticulocytosis, increased lactate dehydrogenase levels, increased unconjugated bilirubin levels and decreased haptoglobin levels should prompt general physicians to consider haemolysis as a differential diagnosis. When further approaching haemolytic anaemia, subdividing patients into those who are 'direct antiglobulin test (DAT) positive' (immune) or 'DAT negative' (non-immune) is a simple and clinically relevant way to start to formulate a cause for the haemolytic anaemia. Immune causes of haemolytic anaemia include autoimmune haemolytic anaemia, drugs and delayed haemolytic transfusion reactions. Non-immune causes include the haemoglobinopathies (such as sickle cell disease) and microangiopathic haemolytic anaemias (such as disseminated intravascular coagulation). Early supportive care in haemolytic anaemia is important and may involve blood transfusions as well as interventions to slow the rate of haemolysis, such as steroids in autoimmune haemolytic anaemia. Complications of haemolysis include pigment gallstones, high-output cardiac failure and thromboembolism. Haemolytic anaemia should be referred to the haematologist for further investigation, however, the recognition and early management by the general physician is imperative in improving the patient's outcome.

Autoimmune Hemolytic Anemia: Diagnosis and Differential Diagnosis.

The causes of hemolytic anemia are numerous and a systematic approach is critical for proper identification and classification. The direct antiglobulin test can establish the diagnosis and subclassify the majority of autoimmune hemolytic anemias. Further testing to identify the driver of AIHA can have significant implications in overall management. Advanced testing for rare nonimmune acquired hemolytic anemias or hereditary hemolytic anemias may be necessary if DAT testing is negative.