Clinical Approach to Immune-Mediated Hemolytic Anemia and Thrombocytopenia.

Primary immune mediated hemolytic anemia (IMHA) and thrombocytopenia (IMTP) are rare in horses with the conditions more commonly occurring secondary to underlying disease. Several case reports have suggested a link between neoplasia and immune-mediated destruction of platelets and red blood cells. Diagnostic investigations should therefore focus on identifying possible underlying causes such as infections and neoplasia. Immunosuppressive therapy with corticosteroids and azathioprine is the mainstay of treatment but should be used cautiously in cases where underlying infection has not been excluded. Given the frequent association of secondary IMHA and IMTP cases with neoplasia, primary cases generally have a better prognosis.

The evolving management algorithm for the patient with newly diagnosed cold agglutinin disease.

INTRODUCTION: Cold agglutinin disease (CAD) is driven by IgM autoantibodies reactive at <37°C and able to fix complement. The activation of the classical complement pathway leads to C3-mediated extravascular hemolysis in the liver and to intravascular hemolytic crises in case of complement amplifying conditions. C3 positivity at direct Coombs test along with high titer agglutins are required for the diagnosis. Treatment is less standardized. AREAS COVERED: This review recapitulates CAD diagnosis and then focus on the evolving management of the disease. Both current approach and novel targeted drugs are discussed. Literature search was conducted in PubMed and Scopus from 2000 to 2024 using 'CAD' and 'autoimmune hemolytic anemia' as keywords. EXPERT OPINION: Rituximab represents the frontline approach in patients with symptomatic anemia or disabling cold-induced peripheral symptoms and is effective in 50-60% of cases. Refractory/relapsing patients are an unmet need and may now benefit from complement inhibitors, particularly the anti-C1s sutimlimab, effective in controlling hemolysis thus improving anemia in >80% of patients, but not active on cold-induced peripheral symptoms. Novel drugs include long-acting complement inhibitors, plasma cells, and B-cell targeting agents (proteasome inhibitors, anti-CD38, BTKi, PI3Ki, anti-BAFF). Combination therapy may be the future answer to CAD unmet needs.

Case of autoimmune haemolytic anaemia, possibly secondary to vedolizumab in ulcerative colitis, successfully treated with rituximab.

Autoimmune haemolytic anaemia (AIHA), autoimmune destruction of erythrocytes is most commonly secondary to immunomodulated conditions. The association between AIHA and inflammatory bowel disease (IBD) has been poorly investigated. We aim to report a case of AIHA in a patient with ulcerative colitis (UC) treated with vedolizumab.A case of a woman in her 30s with UC that after the initiation of vedolizumab developed severe anaemia. Due to the absence of visible blood losses and a positive Coombs direct test, the diagnosis of AIHA was established. The patient initially initiated prednisolone with no response. Rituximab had to be introduced. After a few days with this therapy, there was a clinical and analytical improvement.AIHA must be taken into account as a possible cause of anaemia in patients with IBD. The differential diagnosis between IBD or drug-related (namely vedolizumab) as the cause of the AIHA is complex and almost impossible to establish.

Multiple autoimmune disorders refractory to glucocorticoids after allogeneic hematopoietic stem cell transplantation: a case report and review of the literature.

We report here the case of a 50-year-old man who was first diagnosed with myelodysplastic syndrome with excess blasts-2 (MDS-EB-2) and underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) in 2019, resulting in complete remission. However, he was diagnosed in 2021 with several autoimmune disorders, including autoimmune hepatitis (AIH), Hashimoto's thyroiditis (HT), and autoimmune hemolytic anemia (AIHA). This is referred as multiple autoimmune syndrome (MAS), which is a rare occurrence after allo-HSCT, as previously noted in the literature. Despite being treated with glucocorticoids, cyclosporine A, and other medications, the patient did not fully recover. To address the glucocorticoid-refractory MAS, a four-week course of rituximab (RTX) at a weekly dose of 100mg was administered, which significantly improved the patient's condition. Thus, this case report underscores the importance of implementing alternative treatments in patients with post-transplant autoimmune diseases, who are glucocorticoid-refractory or glucocorticoid-dependent, and highlights the effectiveness of RTX as second-line therapy.

Successful treatment of concurrent cold agglutinin disease and myelodysplastic syndrome.

Herein, we describe a case of severe anemia presenting with myelodysplastic syndrome with cold agglutinin disease that was successfully treated by a moderate dose of steroids followed by cyclosporine. In patients with myelodysplastic syndrome, autoimmunity in erythroid cells is occasionally demonstrated, and autoimmune hemolytic anemia is seen in some patients. However, hemolytic anemia with cold agglutinin in patients with myelodysplastic syndrome is less common, and the effect of corticosteroids for autoimmune hemolytic anemia caused by cold agglutinin is thought to be limited. Although the elevated levels of reticulocytes and LDH are usually caused by ineffective hematopoiesis in myelodysplastic syndrome, clinicians should be aware of latent cold agglutinin disease. In the present case, in addition to the improvement of erythroid dysplasia, the corticosteroid-sparing effect on cold agglutinin disease may have played a role in the mechanism underlying the effectiveness of cyclosporine.

Daratumumab monotherapy in refractory warm autoimmune hemolytic anemia and cold agglutinin disease.

ABSTRACT: Autoimmune hemolytic anemia (AIHA) is a rare autoantibody-mediated disease. For steroid and/or rituximab-refractory AIHA, there is no consensus on optimal treatment. Daratumumab, a monoclonal antibody targeting CD38, could be beneficial by suppression of CD38+ plasma cells and thus autoantibody secretion. In addition, because CD38 is also expressed by activated T cells, daratumumab may also act via immunomodulatory effects. We evaluated the efficacy and safety of daratumumab monotherapy in an international retrospective study including 19 adult patients with heavily pretreated refractory AIHA. In warm AIHA (wAIHA, n = 12), overall response was 50% with a median response duration of 5.5 months (range, 2-12), including ongoing response in 2 patients after 6 and 12 months. Of 6 nonresponders, 4 had Evans syndrome. In cold AIHA (cAIHA, n = 7) overall hemoglobin (Hb) response was 57%, with ongoing response in 3 of 7 patients. One additional patient with nonanemic cAIHA was treated for severe acrocyanosis and reached a clinical acrocyanosis response as well as a Hb increase. Of 6 patients with cAIHA with acrocyanosis, 4 had improved symptoms after daratumumab treatment. In 2 patients with wAIHA treated with daratumumab, in whom we prospectively collected blood samples, we found complete CD38+ T-cell depletion after daratumumab, as well as altered T-cell subset differentiation and a severely diminished capacity for cell activation and proliferation. Reappearance of CD38+ T cells coincided with disease relapse in 1 patient. In conclusion, our data show that daratumumab therapy may be a treatment option for refractory AIHA. The observed immunomodulatory effects that may contribute to the clinical response deserve further exploration.

Autoimmune cytopenias in children: When to think of primary immunodeficiency?

Autoimmune cytopenias are defined by autoantibodies' immune destruction of one or more blood elements. Most often it is autoimmune hemolytic anemia or immune thrombocytopenia or both that define Evans syndrome. It may be secondary to infection or to underlying pathology such as systemic autoimmune disease or primary immunodeficiency, especially when it becomes chronic over several years. Primary Immunodeficiencies or inborn errors of immunity (IEI) are no longer defined solely by infections: autoimmunity is part of the clinical features of several of these diseases. It is dominated by autoimmune cytopenias, in particular, immune thrombocytopenia (ITP) and autoimmune hemolytic anaemia (AIHA). The challenges for the clinician are the situations where autoimmune cytopenias are chronic, recurrent and/or refractory to the various long-term therapeutic options. Most of these therapies are similar in action and generally consist of non-mediated immune suppression or modulation. In these situations, primary Immunodeficiencies must be diagnosed as soon as possible to allow the initiation of a targeted treatment and to avoid several ineffective therapeutic lines.

Autoimmune hemolytic anemia and thrombocytopenia in a Chinese patient with heterozygous NBAS mutations: Case report.

RATIONALE: Neuroblastoma amplified sequence (NBAS)-associated disease is an autosomal recessive disorder and a broad spectrum of clinical symptoms has been reported. However, autoimmune mediated hemolytic anemia (AIHA) is rarely reported in NBAS disease. PATIENT CONCERNS: A now 21-year-old male harbors heterozygous variants of c.6840G>A and c.335 + 1G>A and was found had retarded growth, hypogammaglobulinemia, B lymphopenia, optic atrophy, horizontal nystagmus, slight splenomegaly and hepatomegaly since childhood. This case had normal hemoglobin level and platelet count in his childhood. He developed AIHA first in his adulthood and then thrombocytopenia during the treatment of AIHA. The mechanism underlying a case with pronounced hypogammaglobulinemia and B lymphopenia is elusive. In addition to biallelic NBAS mutations, a germline mutation in the ANKRD26 (c.2356C>T) gene was also detected. So either autoimmune or ANKRD26 mutation-mediated thrombocytopenia is possible in this case. INTERVENTION AND OUTCOME: He was initially managed with steroid and intermittent intravenous immunoglobulin supplement. After treatment, he responded well with a normalization of hemoglobin and serum bilirubin. But the patient subsequently experienced severe thrombocytopenia in addition to AIHA. He was then given daily avatrombopag in addition to steroid escalation. He responded again to new treatment, with the hemoglobin levels and platelet counts went back to the normal ranges. Now he was on de-escalated weekly avatrombopag and low-dose steroids maintenance. CONCLUSION: The phenotype of this case indicates that c.335 + 1G>A NBAS variant is probably a pathogenic one and c.2356C>T ANKRD26 variant is improbably a pathogenic one. AIHA may respond well to steroid even when happened in patients with NBAS disease.

Healthcare resource utilization of patients with warm autoimmune hemolytic anemia initiating first line therapy of oral corticosteroids with or without rituximab.

This retrospective cohort study described real-world treatment patterns and healthcare resource utilization (HCRU) of patients with warm autoimmune hemolytic anemia (wAIHA) initiating treatment with first-line (1L) oral corticosteroids (OCS) + rituximab (R) compared to 1L OCS. Patients with a wAIHA diagnosis code (D59.11) between 8/2020-3/2022 were identified using US pharmacy and medical claims databases. Patients initiating 1L OCS ± R were identified (date of initiation = 'index date') with a 1-year pre-index period and a variable (minimum 1-year) follow-up period. The final sample comprised 77 1L OCS + R patients and 400 1L OCS patients (~ 60% female, mean age > 64 years). Over the 1-year follow-up, HCRU was higher in the OCS + R cohort with higher mean number of physician office visits (22.9 and 14.4; p < 0.01), including hematology/oncology office visits, and higher utilization of rescue therapy (59.7% and 33.3%; p < 0.01), driven by higher use of injectable corticosteroids. Patients in OCS + R and OCS groups completed 1L therapy after a similar mean duration of 103.5 and 134.6 days, respectively (p = 0.24). In the majority of patients, second-line (2L) therapy was initiated at a similar timepoint: 66.2% OCS + R and 72.0% OCS cohorts (p = 0.31) initiated 2L in a mean of 218.3 and 203.2 days (p = 0.76) after the end of 1L treatment, respectively. The addition of rituximab in 1L did not extend the remission period, with most patients in both cohorts initiating 2L therapy within less than 1 year of completing 1L treatment. 1L OCS + R patients also had substantial HCRU burden. More effective novel therapies are needed to address the high unmet need in wAIHA.

Safety, tolerability, and activity of the active C1s antibody riliprubart in cold agglutinin disease: a phase 1b study.

ABSTRACT: Cold agglutinin disease is a rare autoimmune hemolytic anemia characterized by complement pathway-mediated hemolysis. Riliprubart (SAR445088, BIVV020), a second-generation classical complement inhibitor, is a humanized monoclonal antibody that selectively inhibits only the activated form of C1s. This Phase 1b study evaluated the safety, tolerability, and effect on hemolysis of riliprubart in adult patients with cold agglutinin disease. On day 1, 12 patients received a single IV dose of either 30 mg/kg (n = 6) or 15 mg/kg (n = 6) of riliprubart and were subsequently followed for 15 weeks. Riliprubart was generally well tolerated; there were no treatment-emergent serious adverse events, or treatment-emergent adverse events leading to death or permanent study discontinuation. There were no reports of serious infections, encapsulated bacterial infections including meningococcal infections, hypersensitivity, or thromboembolic events. Rapid improvements in hemoglobin (day 5) and bilirubin (day 1) were observed in both treatment cohorts. Mean hemoglobin levels were maintained at >11.0 g/dL from day 29 and mean levels of bilirubin were normalized by day 29; both responses were maintained throughout the study. Improvements in clinical markers closely correlated with a sustained reduction in the 50% hemolytic complement (CH50) throughout the study. Mean C4 levels, an in vivo marker of treatment activity, increased 1 week after treatment with either dose of riliprubart and were sustained throughout the study. In conclusion, a single IV dose of riliprubart was well tolerated, and led to rapid classical complement inhibition, control of hemolysis, and improvement in anemia, all of which were sustained over 15 weeks. This trial was registered at www.ClinicalTrials.gov as #NCT04269551.

Fostamatinib for warm antibody autoimmune hemolytic anemia: Phase 3, randomized, double-blind, placebo-controlled, global study (FORWARD).

Warm antibody autoimmune hemolytic anemia (wAIHA) is characterized by hemolysis and symptomatic anemia with no approved treatment options. Fostamatinib is an oral spleen tyrosine kinase inhibitor approved in the US and Europe for treatment of adults with chronic immune thrombocytopenia. In this phase 3 study, patients with an insufficient response to ≥1 prior wAIHA treatment were randomized to fostamatinib or placebo. The primary endpoint was the proportion of patients to achieve a durable hemoglobin (Hgb) response (Hgb ≥10 g/dL and increase from baseline of ≥2 g/dL on 3 consecutive visits) during the 24-week treatment period. Ninety patients were randomized, 45 to each arm. Of the fostamatinib-treated patients, 35.6% achieved a durable Hgb response versus 26.7% on placebo (p = .398). A post hoc analysis revealed a large placebo response in Eastern European patients. Significantly more patients on fostamatinib from North America, Australia and Western Europe exhibited a durable Hgb response compared to placebo (36% vs. 10.7%, p = .030). After censoring for Hgb values impacted by steroid rescue received during screening and excluding 2 placebo patients found to likely not have wAIHA, a reanalysis demonstrated a difference in durable Hgb response between fostamatinib and placebo (15/45 [33.3%] vs. 6/43 [14.0%], p = .0395). At least 1 AE was reported in 42 (93.3%) and 40 (88.9%) patients receiving fostamatinib and placebo, respectively. The most common AEs in the fostamatinib group were diarrhea (26.7%), hypertension (24.4%), and fatigue (15.6%). In this study, fostamatinib demonstrated a clinically meaningful benefit for patients in Western regions, and no new safety signals were identified.

Prevention of Rhesus-D Alloimmunization in the First Trimester of Pregnancy: Economic Analysis of Three Management Strategies.

Anti-D alloimmunization in the first trimester of pregnancy has long been the subject of prevention with anti-D immunoglobulins during events at risk of fetomaternal hemorrhage. Although the efficacy of preventing anti-D alloimmunization by an injection of immunoglobulin at 28 weeks of gestation (WG) is obvious, the literature provides little evidence of the effectiveness before 12+6 WG and several countries have modified their recommendations. In the presumed absence of a difference in alloimmunization risk between early and late prevention, our objective was to evaluate and compare the cost of treatment for 3 alloimmunization prevention strategies in France, the United Kingdom, and the Netherlands. This was a single-center retrospective study. Our target population included all women who received anti-D immunoglobulins (Rhophylac) in the first trimester of pregnancy before 12+6 WG at Nantes University Hospital in 2018 (N = 356). Within the target population, 2 other populations were constituted based on British (N = 145) and Dutch (N = 142) clinical practice guidelines (CPG). These 3 populations were analyzed for the comparative cost of treatment for prevention from a health system perspective. The average cost of Rhophylac alloimmunization prevention for 1 episode was €117.8 from a health system perspective. The total cost attributed to prevention in 2018 at Nantes University Hospital (N = 356) was €41,931.4 according to this perspective. If the UK CPG or Dutch CPG had been applied to the Nantes target population, a saving of around 60% would have been achieved. At the national level, the cost according to the health system perspective specifically attributable to induced abortion (N estimated = 26,916) could represent a total cost of €3,170,704. This study highlighted the high cost of the French prevention strategy in the first trimester of pregnancy compared with British or Dutch strategies. The modification of our practices would allow substantial financial savings to the French health system but would also avoid the nonrecommended exposure to a blood product at this term, would allow a faster medical management and a relief of the care system.

Recombinant erythropoietin in autoimmune hemolytic anemia with inadequate bone marrow response: a prospective analysis.

ABSTRACT: Up to 30% of patients with autoimmune hemolytic anemia (AIHA) show inadequate bone marrow (BM) compensatory response with inappropriately low levels of reticulocytes and endogenous erythropoietin. Ineffective BM compensation is associated with more severe anemia, transfusion need, and hospital admission, and treatment with recombinant erythropoietin (rEPO) may be beneficial. Here, we prospectively analyzed the efficacy and safety of rEPO in a single-center cohort of 47 patients with AIHA with inadequate reticulocytosis and endogenous erythropoietin at baseline. Epoetin alpha 40 000 international units per week were administered subcutaneously until hemoglobin (Hb) >11 g/dL and then tapered off. Overall response was 55% at 15 days, 74% at 1 month, 74% at 3 months, 80% at 6 months, and 91% at 12 months. Consistently, Hb values significantly increased from baseline to each subsequent time point (P<.001) with a median increase of +1.4, +2.4, +3.4, +3.8, and +4.4 g/dL, respectively. Transfusion needs reduced from 30% to <10% at 15 days and thereafter (P < .001). Concomitant medications included prednisone or methylprednisolone (N = 40, stable since >2 weeks from enrollment), mycophenolate mofetil (N = 1, ongoing since >3 months from enrollment), and rituximab (N = 7 patients with cold agglutinin disease from day 8). No association between concomitant medications and response to rEPO was found. Treatment was generally safe without rEPO-related severe adverse events. The comparison with an AIHA population not treated with rEPO showed a significant benefit of rEPO at 15 days and 1 month on response and Hb increase. These data support the use of rEPO as an add on to standard immunosuppression in AIHA with inadequate BM compensation. This trial was registered at www.clinicaltrials.gov as #NCT05931718.

Autoimmune Hemolytic Anemia in Children: Clinical Profile and Outcome.

OBJECTIVE: To discover the common triggers for AIHA in children, their clinical profile, treatment response, and outcome. METHODS: This was an ambispective descriptive study conducted between 2013 and 2020. Children aged 1 mo to 14 y with hemolytic anemia and a positive direct antiglobulin test (DAT) were included. Children with a positive DAT but without any clinicolaboratory evidence of hemolysis were excluded. Data were collected from a structured pro forma with particulars comprising clinicolaboratory profile, treatment administered, and disease outcome. RESULTS: A total of 46 children (aged between 1 mo and 14 y) were enrolled in the study. The mean age of onset was 8.7 (± 4.34) y, and 24 (52.8%) were males. Secondary causes were observed in 29 (63%) cases, while the primary cause was found in 17 (37%). Systemic lupus erythematosus (SLE) was the common trigger in 13 (45%) cases, followed by malignancy in 4 (14%) cases. Pallor (98%), hepatomegaly (72%), and splenomegaly (48%) were the most commonly observed clinical signs. The mixed immunophenotype was observed in 27 (59%) cases, followed by warm type in 12 (26%) and cold agglutinin type in 7 (15%) cases. All children received glucocorticoid therapy, and mycophenolate mofetil was commonly used as second-line therapy in 15 (33%) cases. 13 cases (71%) of primary AIHA and only 4 (14%) cases of secondary anemia achieved complete remission. Overall, 7 children (15%) died, all belonging to secondary AIHA. CONCLUSION: Secondary AIHA was more common than primary in the present study, and SLE was the standard trigger. Primary AIHA carries a better prognosis than secondary.