Mixed-type autoimmune hemolytic anemia: differential diagnosis and a critical review of reported cases

BACKGROUND: Autoimmune hemolytic anemia (AIHA) is usually classified as either warm or cold type. During the past few decades, mixed types (Mxs) have also been described in a number of cases (6%‐8% of AIHA), often without serologic data to support the diagnosis. In this study, we demonstrate that the incidence of Mx AIHA in our institution is extremely rare. STUDY DESIGN AND METHODS: Between August 1998 and August 2007, all in‐ and outpatients with detectable warm autoantibodies (WABs) were included in this study. Serologic testing was performed using standard techniques for the detection of red blood cell antibodies. RESULTS: From a total of 2194 patients with detectable WABs, only 2 patients (<0.1%) developed both WABs and cold agglutinins (CAs), which in the presence of clinical evidence of hemolytic anemia, satisfies the criteria for Mx AIHA. Only 1 of these patients, however, showed cold and warm hemolysis. Insignificant CAs at temperatures of not more than 24°C were found in 242 patients. CONCLUSION: There is evidence that the presence of CAs with high thermal amplitude and WABs may lead to confusion and misdiagnosis in some patients with AIHA. This study demonstrates that Mx AIHA is less common than previously reported.     

Aquired immune hemolytic anemias

Aquired immune hemolytic anemias are classified in autoimmune hemolytic anemia (AIHA) of warm type, cold agglutinine disease, paroxysmal cold hemoglobinuria, drug-induced immune hemolytic anemia, and paroxysmal nocturnal hemoglobinuria. The autoantibodies in AIHA of warm type react most strongly at 37 degrees C (warm autoantibodies). They are of the IgG, less commonly of the IgM and IgA classes. The cause of autoimmunization remains obscure in 50% of the patients (idiopathic AIHA). In the remaining cases, the AIHA is associated with other diseases. Corticosteroids are the mainstay of therapy, but most patients with AIHA of warm type require additional treatment with azathioprine or other drugs. Cold agglutinins are the cause of hemolysis in about 10% of patients with AIHA. Paroxysmal cold hemoglobinuria (Donath-Landsteiner) is less common and occur in children following infections. Drugs are the cause of hemolysis in about 10% of all cases with AIHA. The true incidence of alloimmune hemolytic anemias including neonatal immune hemolytic anemias is unknown. The paroxysmal nocturnal hemoglobinuria is rare. It is caused by complement activation due to aquired membrane defects.     

Clinical significance of serologic markers related to red blood cell autoantibodies production after red blood cell transfusion—severe autoimmune hemolytic anemia occurring after transfusion and alloimmunization: successful treatment with rituximab

BACKGROUND: The association of autoantibody formation with blood transfusion was previously noted. Severe autoimmune hemolytic anemia (AIHA) diagnosed after red blood cell (RBC) transfusion determined us to undertake this study and investigate the incidence and clinical significance of autoantibodies occurring after transfusion by a retrospective review of blood bank and medical records.
STUDY DESIGN AND METHODS: We report a lymphoma patient who developed severe autohemolysis after blood transfusion and alloantibody production. The hemolysis was refractory to steroids and chemotherapy and ceased after rituximab. We also retrospectively assessed the blood bank records for a 2-year period to identify the patients who developed autoantibodies after blood transfusion and examined laboratory, clinical features, and outcome.
RESULTS: From January 2005 through December 2006, 375 direct antiglobulin tests (DATs) and 3409 indirect antiglobulin tests (IATs) were found to be positive. Thirty-eight patients with positive DATs and IATs had demonstrable RBC warm-type autoantibodies occurring after blood transfusion; 27 of them had also one or more alloantibodies. Clinical and laboratory signs of hemolysis were absent in all patients (except the case reported). In another 5 patients alloantibodies were retrieved from RBC eluate and serum without evidence of autoantibodies; therefore, a delayed serologic transfusion reaction was diagnosed.
CONCLUSION: RBC autoantibodies are quite commonly found after blood transfusion. Nevertheless, clinically significant AIHA is a rare but at times a life-threatening phenomenon. We describe a first case of successful treatment with rituximab of refractory posttransfusion AIHA. Rituximab must be further evaluated for this indication.     

Serologic findings in autoimmune hemolytic anemia associated with immunoglobulin M warm autoantibodies

BACKGROUND: Autoimmune hemolytic anemia (AIHA) associated with immunoglobulin M (IgM) warm autoantibodies is unusual but often severe, with more fatalities than other types of AIHA. Diagnosing this type of AIHA can be difficult because routine serologic data are not always informative.
STUDY DESIGN AND METHODS: Forty-nine cases of IgM warm AIHA in 25 years were studied by serologic methods.
RESULTS: Routine direct antiglobulin tests (DATs) detected red blood cell (RBC)-bound C3 in 90 percent of cases (65% had C3 but no immunoglobulin G [IgG] on their RBCs) and IgG in 24 percent. IgM was detected on 29 of 47 (62%) patients' RBCs; RBC-bound IgM was detected in 14 of 47 cases by a tube DAT method and in an additional 15 of 21 (71%) cases using fluorescein isothiocyanate anti-IgM and flow cytometry. Eighty-one percent of eluates from patients' RBCs reacted. Warm autoagglutinins were present in 94 percent of serum samples; untreated and enzyme-treated RBCs were hemolyzed at 37°C by 13 and 65 percent of serum samples, respectively. Most agglutinins were optimally reactive at 30 to 37°C. Patients' RBCs were spontaneously agglutinated in 78 percent of cases; washing with 37°C saline or treating RBCs with dithiothreitol resolved this problem. Clear specificity of autoantibody was defined in 35 percent of serum samples.
CONCLUSION: IgM warm AIHA can be confused with cold agglutinin syndrome and "mixed/combined"-type AIHA; a serologic workup by a specialist reference laboratory can help with the diagnosis.     

One center's experience: the serology and drugs associated with drug-induced immune hemolytic anemia--a new paradigm

BACKGROUND: Drug-induced immune hemolytic anemia (DIIHA) is an uncommon finding characterized by a sudden decrease in hemoglobin after treatment with the putative drug. The full range of drugs causing DIIHA and the initial serologic presentation are not fully appreciated. This work identifies additional drugs associated with DIIHA and offers additional insights about diagnosis. STUDY DESIGN AND METHODS: A 20-year retrospective review of testing in one laboratory was performed. Patient sex, age, medication history, initial direct antiglobulin test (DAT) and indirect antiglobulin test, method of drug-dependent antibody (DDA) detection, and specificity were reviewed. RESULTS: Seventy-one patients with 73 DDAs to 23 different drugs were identified. The following DDA specificities were identified: cephalosporins (37), penicillin and/or penicillin derivatives (12), nonsteroidal anti-inflammatory drugs (NSAIDs) (11), quinine and/or quinidine (7), and others (6). Fifty-two percent (37) were due to cephalosporins with 27 cefotetan-dependent antibodies detected. Four NSAIDs required urinary metabolite for detection. DAT was strongly positive, at least 2+, in 75 percent (51/68) of patients with a positive DAT. Initial eluate was negative in 52 patients, weak positive (<2+) in 14 patients, and strong positive (>or=2+) in 2 patients. Serologic results showed characteristics of warm autoimmune hemolytic anemia (AIHA) in 22 or 31 percent of all cases and cold-reactive AIHA in 2 cases. CONCLUSIONS: It is important to consider DIIHA when a patient serologically presents as either warm- or cold-type AIHA to avoid erroneous diagnosis. Based on these findings, the strength of the initial DAT is much stronger than previously reported for all types of drug-induced immune hemolysis. This report is also unique in the number of NSAIDs reported. A new classification of categorizing DDA is proposed.     

Autoimmune hemolytic anemia associated with anti-Sc1

A case of autoimmune hemolytic anemia (AIHA) in a young child is described. The hemolysis was resistant to steroid therapy but responded to splenectomy and intravenous immunoglobulin. The autoantibody was shown to be anti-Sc1 by both serologic and immunoblotting techniques. This seems to be the first report of an autoanti-Sc1 detected by immunoblotting and the first example of AIHA in a child caused by autoanti-Sc1.     

Autoimmune hemolytic anemia

Diagnosis of autoimmune hemolytic anemia (AIHA) requires both serologic evidence of an autoantibody and hemolysis. Based on the characteristic temperature reactivity of the autoantibody to red cell membranes, AIHA is classified into warm AIHA or cold AIHA (cold agglutinin disease and paroxysmal cold hemoglobinuria). Sensitized RBCs are destructed by intravascular and/or extravascular hemolysis. On the basis of etiology, AIHA are classified as idiopathic or secondary. The common cause of secondary AIHA is lymphoproliferative disorders, autoimmune diseases, and infections. The first line therapy of patients with warm AIHA is glucocorticoids and primary treatment for cold AIHA is avoiding cold exposure. The other standard treatments include splenectomy and immunosuppressive drugs. Recently, rituximab, a monoclonal anti-CD20 antibody, has been used in refractory AIHA with excellent responses.     

Production of human warm-reacting red cell monoclonal autoantibodies by Epstein-Barr virus transformation

Monoclonal antibody technology has been used in both murine and human systems to produce a variety of antibodies that react with the human red cell (RBC). RBC monoclonal autoantibodies have been obtained from animal models of autoimmune hemolytic anemia (AIHA), but to date no warm-reactive monoclonal autoantibodies have been generated from human B cells. Using the Epstein-Barr virus (EBV) transformation method, clones of RBC autoantibodies were generated from two patients with AIHA. These antibodies reacted preferentially at 37 degrees C, agglutinated or bound to a variety of different RBC phenotypes, and were IgM in nature. The serologic reactivity of one clone showed a relative specificity to e+ RBCs that was similar to that seen in the patient's serum. These results are the first to demonstrate that warm-reactive RBC autoantibodies can be obtained from patients with AIHA using the technique of EBV transformation, and they further substantiate the existence of warm-reactive IgM RBC autoantibodies in the spectrum of warm AIHA.     

Clinical application of a flow cytometric direct antiglobulin test

BACKGROUND: The clinical application of flow cytometric direct antiglobulin test (FC-DAT) has rarely been evaluated for patients with various diseases including immune and nonimmune hemolytic anemia.
STUDY DESIGN AND METHODS: Blood samples from 380 patients with a variety of diseases were studied using the tube direct DAT and FC-DAT. The results of tube DAT and FC-DAT were compared. The predictive values of DAT for hemolysis were evaluated.
RESULTS: Of 57 patients with autoimmune hemolytic anemia (AIHA), 6 of the 17 with a negative tube DAT (immunoglobulin G [IgG]) had a positive FC-DAT (IgG) and 23 of the 36 patients with a negative tube DAT (complement 3d [C3d]) had a positive FC-DAT (C3d). In 57 patients with AIHA, the incidence of positive results of FC-DAT (IgG) and tube DAT (IgG) were similar (42 positive vs. 40 positive); but in 323 patients without AIHA, the incidence of positive FC-DATs (IgG) was higher than that of tube DAT (IgG; 47 positive vs. 9 positive). The higher incidence of positive FC-DAT (C3d) than that of tube DAT (C3d) was seen in patients with AIHA (42 positive vs. 21 positive) as well as in patients without AIHA (61 positive vs. 5 positive). Both DAT (IgG) and DAT (C3d) positive has highest positive predictive value for hemolysis, followed by DAT (IgG) alone positive and DAT (C3d) alone positive.
CONCLUSIONS: FC-DAT is a complementary test for diagnosing AIHA. There is a synergistic effect of the red blood cell–bound IgG and complement in predicting hemolysis.     

Autoimmune hemolytic anemia in pediatric liver or combined liver and small bowel transplant patients: a case series and review of the literature

BACKGROUND: Autoimmune hemolytic anemia (AIHA) occurring after solid organ transplantation is an infrequently reported entity. We describe in this report six cases of AIHA in pediatric liver or combined liver and small bowel transplant patients. STUDY DESIGN AND METHODS: We retrospectively identified and reviewed the records of pediatric liver or combined liver and small bowel transplant patients with both serologic and clinical evidence of AIHA. We also performed an English language literature review for prior publications of AIHA occurring after solid organ transplantation. RESULTS: We identified six patients presenting with severe hemolysis 9 months to 14 years after transplantation. All six developed warm AIHA, and two had concomitant cold agglutinins. All except one patient received various therapeutic combinations including steroids, intravenous immune globulin, rituximab, plasmapheresis, splenectomy, and vincristine. Five patients achieved remission 2 weeks to 3 months after presentation. Although tacrolimus has been speculated to play a causative role in the development of AIHA after organ transplantation, our case series demonstrated slightly better outcomes despite continuing tacrolimus compared to published cases where most patients either received significantly reduced doses of tacrolimus or were switched to a different immunosuppressant (83% vs. 76% cumulative literature remission rate). CONCLUSION: AIHA may occur in solid organ transplant patients at a much higher frequency than previously believed. Hemolysis is often severe and resistant to steroid treatment alone. Thus early diagnosis and institution of aggressive multimodality treatment, including the use of rituximab, may be needed to achieve remission.     

Exacerbation of autoimmune hemolytic anemia associated with pure red cell aplasia after COVID-19: A case report

Autoimmune hemolytic anemia (AIHA) and pure red cell aplasia (PRCA) are rare complications of coronavirus disease 2019 (COVID-19). Herein, we report the case of a 28-year-old Japanese man who showed severe AIHA exacerbation associated with PRCA after COVID-19. AIHA was diagnosed and maintained for 5 years. Approximately 4 weeks after COVID-19, the patient developed severe anemia (hemoglobin level, 3.4 g/dL). Laboratory test results confirmed hemolytic exacerbation of IgG-mediated warm-type AIHA. Despite the hemolysis phase, the bone marrow revealed extreme hypoplasia of erythroblasts with a decreased reticulocyte count, similar to that observed in patients with PRCA. During oral prednisolone treatment, the patient recovered from anemia and showed increased reticulocyte count and reduced hypoplasia of marrow erythroblasts. Exacerbation of AIHA and PRCA was triggered by COVID-19 because other causes were ruled out. Although this case report highlights that COVID-19 could lead to hematological complications such as AIHA and PRCA, the exact mechanisms remain unclear.     

23例温冷双抗体型自身免疫性溶血性贫血的临床特征

目的 了解近十年温冷双抗体型自身免疫性溶血性贫血（AIHA）患者的临床特征，以加深对该病的认识。方法 对1994年1月至2004年4月诊断的23例温冷双抗体型AIHA的临床表现、实验室特征及治疗反应进行回顾性分析。结果 近十年温冷双抗体型AIHA在同期AIHA中占22．1％，较20世纪80年代的17．6％有所增加；原发性病例占73．9％；女性多见；自身抗体的类型以复合型为主，含IgM抗体者多见（56．5％），抗体温幅及补体水平与溶血程度相关；对肾上腺皮质激素合并其它免疫抑制剂反应较好；中位随访时间4个月，复发率为77．8％。结论 温冷双抗体型AIHA是一种女性多见、原发性为主、与抗体种类和温幅及补体激活相关、复发率较高的溶血性疾病，联合免疫抑制治疗效果较好。     

Levofloxacin-induced autoimmune hemolytic anemia

OBJECTIVE: To report a case of autoimmune hemolytic anemia (AIHA) secondary to levofloxacin. CASE SUMMARY: An 82-year-old white man was treated with levofloxacin 500 mg/d for cellulitis. Three days following completion of levofloxacin therapy, the patient presented to the emergency department with severe jaundice, dizziness, and loss of vision. He received packed red blood cells (PRBCs) and was discharged home. Two days later at the follow-up visit, he was diagnosed with AIHA secondary to levofloxacin. The patient was hospitalized and treated with a tapering dose of prednisone and additional PRBC infusion. He was discharged from the hospital in stable condition after 3 days. Repeated hematologic laboratory studies following discharge demonstrated that the hemolytic anemia had resolved. DISCUSSION: Hemolytic anemia due to levofloxacin is an extremely rare, but potentially fatal, adverse drug event. An objective causality assessment revealed that the adverse reaction was probable. To our knowledge, this is the first published case of levofloxacin-induced AIHA. However, there are published case reports of hemolytic anemia with other fluoroquinolones including ciprofloxacin (n = 12) and temafloxacin (n = 95). Temafloxacin was withdrawn from the market in 1992 due to this adverse effect. The mechanism by which levofloxacin triggers hemolytic anemia is unknown. We believe that an immune-mediated reaction is most likely. CONCLUSIONS: Levofloxacin-induced AIHA is a rare but serious complication of therapy. Immediate discontinuation of the offending medication and treatment of the hemolytic anemia are essential. Until more information is available, levofloxacin should not be prescribed for patients with previous reactions to any fluoroquinolone.     

53例患儿疑难配血原因分析与输血对策探讨

目的探讨儿科患者疑难配血的原因及输血对策。方法对郴州市第一人民医院北院(郴州市儿童医院)2017年1月至2019年3月的53例疑难配血标本进行ABO血型正反定型、Rh表型鉴定、吸收放散试验、抗人球蛋白试验、不规则抗体筛查及鉴定试验等相关检测,找出导致配血困难的原因,依据原因采用相应的输血对策。结果53例疑难配血患儿中,以新生儿疑难配血发生率最高(75.5%)。新生儿疑难配血中,ABO血型不合溶血病发生率最高(18例),其次为抗-D溶血病(6例)和纤维蛋白丝干扰(6例)。非新生儿疑难配血中,自身免疫性溶血性贫血(AIHA)7例、同种抗-M 5例、同种抗-E 1例。采用相应输血策略后,仅2例患儿出现输注无效,其余患儿输血效果良好。结论儿科患者疑难配血的原因较多,ABO血型不合溶血病、AIHA分别为导致新生儿与非新生儿疑难配血的主要原因。     

Direct antiglobulin test-negative autoimmune hemolytic anemia in a patient with β-thalassemia minor during pregnancy: A case report

BACKGROUNDSevere refractory anemia during pregnancy can cause serious maternal and fetal complications. If the cause cannot be identified in time and accurately, blind symptomatic support treatment may cause serious economic burden. Thalassemia minor pregnancy is commonly considered uneventful, and the condition of anemia rarely progresses during pregnancy. Autoimmune hemolytic anemia (AIHA) is rare during pregnancy with no exact incidence available. CASE SUMMARYWe report the case of a 30-year-old β-thalassemia minor multiparous patient experiencing severe refractory anemia throughout pregnancy. We monitored the patient closely, carried out a full differential diagnosis, made a diagnosis of direct antiglobulin test-negative AIHA, and treated her with prednisone and intravenous immunoglobulin. The patient gave birth to a healthy full-term baby.CONCLUSIONCoombs-negative AIHA should be suspected in cases of severe hemolytic anemia in pregnant patients with and without other hematological diseases.     

Clinical features and treatment of primary autoimmune hemolytic anemia in childhood

Background and aim

Autoimmune hemolytic anemia (AIHA) is characterized by autoimmune destruction of erythrocytes. In this retrospective study, the clinical, laboratory features and treatment responses of patients with primary AIHA were evaluated.

164例Coombs试验阳性的自身免疫性溶血性贫血的临床研究

目的:研究自身免疫性溶血性贫血(AIHA)的临床特征,进一步指导治疗。方法:采用回顾性分析患者资料,率的比较采用精确概率法,均值比较采用t检验。结果:AIHA多发生在女性,继发性占49％,以胶原系统疾病为主,Coombs分型以IgG C_3型为主IgG IgM阳性的患者临床表现最严重,环孢霉素A(CsA)联用皮质激素组有效率为90.9％。结论:皮质激素仍为治疗AIHA的首选药物,合用CsA可提高疗效,缩短疗程。     

Vaccination-associated immune hemolytic anemia in two children

BACKGROUND: Two children in whom acute autoimmune hemolytic anemia (AIHA) developed after vaccination were studied. CASE REPORTS: The children were a 20-month-old girl and a 21-month-old boy. The diagnosis of AIHA was made in accordance with established criteria (hemolysis, positive DAT, and lack of other reasons for the hemolysis). Serologic tests were performed according to standard technique. RESULTS: The girl experienced two attacks of hemolysis. The first episode occurred 2 weeks after oral polio vaccination, and the second episode was observed 7 months later, when she received a simultaneous vaccination against mumps, rubella, and measles. The DAT was strongly positive with anti-C3d. No autoantibodies were detectable in either episode. The boy experienced acute hemolysis a few days after a simultaneous revaccination against diphtheria-pertussis-tetanus, Haemophilus influenzae, hepatitis B, and polio. The DAT using anti-IgG was strongly positive, and the DAT performed with anti-C3d was weakly positive. CONCLUSION: Vaccination-induced AIHA resembles those forms of AIHA related to infectious diseases, and it may occur more frequently than has been reported.     

自身免疫性溶血性贫血的免疫分型及临床分析

目的 对64例自身免疫性溶血性贫血(AIHA)患者血液中红细胞上结合的抗体进行免疫分型,进一步指导临床治疗.方法 采用免疫分型技术及相关溶血性贫血系列检测法.结果 发病较多的是青壮年,女性多于男性,类型分布以IgG C3型多见,且贫血、溶血程度重,余依次为C3型、IgG型.结论 AIHA免疫分型可判定疾病的严重程度以及为临床治疗提供依据.     

Refractory autoimmune hemolytic anemia in a systemic lupus erythematosus patient: A clinical case report

Warm autoimmune hemolytic anemia (AIHA) is a hematologic disorder with an incidence of 1–3 per 10⁵ individuals/year. Patients with systemic lupus erythematosus (SLE) develop AIHA in 3% of adult cases and 14% of pediatric cases. We report a case of AIHA refractory to multiple lines of treatment in a patient with SLE, who eventually responded to a proteasome inhibitor‐based combination. A patient with systemic lupus erythematous was diagnosed with symptomatic autoimmune hemolytic anemia. The patient was refractory to multiple lines of treatment including prednisone, intravenous immune globulin, methylprednisolone, rituximab, cyclophosphamide, mycophenolate mofetil, and splenectomy. She eventually had a beneficial response to a proteasome inhibitor‐based combination with bortezomib plus mycophenolate mofetil. The treatment of refractory autoimmune hemolytic anemia can be challenging. Patients with AIHA refractory to primary or secondary treatments must resort to receiving novel therapeutic modalities including combinations targeting plasma cell, T‐ and B‐cell proliferation.