Warm autoimmune hemolytic anemia: Advances in pathophysiology and treatment

Mycophenolate Mofetil for the Treatment of Warm Autoimmune Haemolytic Anaemia Post-Rituximab Therapy: A Case Series

Background

Warm autoimmune haemolytic anaemia (wAIHA) is an acquired haemolytic disorder most commonly treated with a combination of corticosteroids, rituximab and/or splenectomy. Third-line therapies for refractory cases include immunosuppressive agents. Mycophenolate mofetil is frequently used in these scenarios, although its use is supported by small studies and anecdotal evidence rather than large-scale data.

Case description

We describe three cases of refractory warm autoimmune haemolytic anaemia successfully treated with mycophenolate mofetil. Case 1: A persistent case of autoimmune haemolytic anaemia in a 56-year-old was ultimately managed with mycophenolate mofetil, leading to successful steroid tapering and stable haemoglobin levels without relapse. Case 2: A woman with a complex oncological history, including lymphoma and breast cancer, achieved remission with mycophenolate therapy, maintaining stability post-steroid treatment. Case 3: Mycophenolate proved effective for a 63-year-old with cirrhosis after recurrent autoimmune anaemia and deep vein thrombosis, enabling cessation of steroids and maintaining remission.

Conclusion

Management of this condition can be challenging and balancing the available treatments is crucial to reduce potential complications from long-term therapies that appear to be ineffective. Our case series demonstrates anecdotal experience on successful use of mycophenolate mofetil for complex refractory cases of wAIHA.

LEARNING POINTS

Warm autoimmune haemolytic anaemia can be a challenging condition to manage. Refractory cases that are steroid-dependent can benefit from trialling steroid-sparing agents such as mycophenolate.Anti-CD20 agents such as rituximab can be very effective in refractory cases, however there is a small percentage of patients that might not be responsive to this monoclonal antibody.Autoimmune haemolytic anaemias can be frequently complicated by thrombotic events, and part of the backbone treatment is establishing good thromboprophylaxis.

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.

Regulatory T-cell dysfunctions are associated with increase in tumor necrosis factor α in autoimmune hemolytic anemia and participate in Th17 polarization

Warm autoimmune hemolytic anemia (wAIHA) is a rare acquired autoimmune disease mediated by antibodies targeting red blood cells. The involvement of CD4 T-helper cells has been scarcely explored, with most findings extrapolated from animal models. Here, we performed quantification of both effector T lymphocytes (Teff) and regulatory T cells (Treg), associated with functional and transcriptomic analyses of Treg in human wAIHA. We observed a shift of Teff toward a Th17 polarization concordant with an increase in serum interleukin-17 concentration that correlates with red blood cell destruction parameters, namely lactate dehydrogenase and bilirubin levels. A decrease in circulating Treg, notably effector Treg, associated with a functional deficiency, as represented by their decrease capability to inhibit Teff proliferation, were also observed. Treg deficiency was associated with a reduced expression of Foxp3, the master transcription factor known to maintain the Treg phenotype stability and suppressive functions. Transcriptomic profiling of Treg revealed activation of the tumor necrosis facto (TNF)-α pathway, which was linked to increased serum TNF-α concentrations that were twice as high as in controls. Treg transcriptomic profiling also suggested that post-translational mechanisms possibly accounted for Foxp3 downregulation and Treg dysfunctions. Since TNF-α participates in the rupture of immune tolerance during wAIHA, its inhibition could be of interest. To this end, the effects of fostamatinib, a SYK inhibitor, were investigated in vitro, and we showed that besides the inhibition of erythrocyte phagocytosis by monocytes, fostamatinib is also able to dampen TNF-α production, thus appearing as a promising multitargeting therapy in wAIHA (clinicaltrials gov. Identifier: NCT02158195).

Pathogenesis, risk factors and therapeutic options for autoimmune haemolytic anaemia in the post-transplant setting

Autoimmune haemolytic anaemia (AIHA) is a rare complication of allogeneic haematopoietic stem cell transplantation (HSCT), observed with an incidence of 1-5%. Paediatric age, diagnosis of non-malignant disease, lympho-depleting agents in the conditioning regimen, use of unrelated donor, graft versus host disease and infections have been associated with a higher risk of AIHA post HSCT. Post-HSCT AIHA is associated with high mortality and morbidity, and it is often very difficult to treat. Steroids and rituximab are used with a response rate around 30-50%. These and other therapeutic strategies are mainly derived from data on primary AIHA, although response rates in post-HSCT AIHA have been generally lower. Here we review the currently available data on risk factors and therapeutic options. There is a need for prospective studies in post-HSCT AIHA to guide clinicians in managing these complex patients.

Alectinib-induced Immune Hemolytic Anemia in a Patient with Lung Adenocarcinoma

Drug-induced immune hemolytic anemia (DIIHA) is a rare condition with an increasing incidence associated with the frequent use of certain drugs. An 85-year-old woman with lung adenocarcinoma prescribed alectinib complained of dyspnea on exertion at our hospital. Based on her laboratory tests results on admission, we focused on the clinical course of anemia and hemolysis progression after alectinib administration. The patient's anemia and hemolysis gradually improved after discontinuation of alectinib, leading to a diagnosis of alectinib-induced IHA, presented here as the first case encountered in a patient with lung adenocarcinoma. Furthermore, we discuss the importance of correlating clinical laboratory findings in DIIHA.

Diagnosis and management of autoimmune hemolytic anemia in children

BACKGROUND AND AIM

The aim of this study is to evaluate the clinical, biological and hematological profiles of autoimmune hemolytic anemia (AIHA) in children and to specify its etiologies, therapeutic modalities, and treatment responses.

METHODS

This is a 14-year retrospective study of AIHA cases collected at the department of pediatric emergency and reanimation of Hedi Chaker University Hospital in Sfax. We included patients under 14 years old with clinical and biological features of hemolysis and a positive direct antiglobulin test (DAT). The selected patients' demographic characteristics, physical signs, laboratory findings, and treatment responses were recorded.

RESULTS

Thirteen cases of AIHA were collected, including 8 girls and 5 boys. The median age at diagnosis was 4 years and 6 months (range: 8 months to 13 years). Consanguinity was reported in 6 cases and 4 patients had a previous infection history. The onset of AIHA was progressive in 9 cases, marked by an anemic syndrome and hemolysis symptoms in 6 and 8 cases, respectively. The clinical triad (pallor, jaundice and splenomegaly) was found in only 4 cases. At the time of diagnosis, the median hemoglobin (Hb) level was 6g/dL (range: 4.2 to 9.2g/dL), anemia was non-regenerative in 2 patients. Thrombocytopenia and neutropenia were noted in 5 and 1 patient, respectively. Peripheral smear examination showed spherocytosis in 2 cases. All the patients had a positive DAT. Of these, 10 were positive with IgG and 3 with both IgG and C3d. AIHA was secondary to other conditions in 9 patients: infection (3 cases), autoimmune disease (4 cases), and immunodeficiency (2 cases). All the patients received first-line corticosteroid therapy but only 8 of them required blood transfusions due to severe anemia. Complete remission was obtained in 7 cases. Corticosteroid resistance and dependence were noted in 1 and 2 cases, respectively. During evolution, additional therapy was indicated in 4 patients and it included cyclosporine A, azathioprine, and mycophenolate mofetil (MMF). After a median follow-up of 4.5 years, the cure rate was 80% and only 1 patient (a boy) died due to his underlying pathology.

CONCLUSION

Our study highlights the rarity, severity, and heterogeneity of etiological contexts of AIHA in children. The therapeutic difficulties justify specific expertise in pediatric hematology.

Efficacy and safety of second-line treatment in Thai patients with primary warm-type autoimmune hemolytic anemia

Objectives:: To investigate the efficacy and safety of second-line treatment in Thai patients with primary warm-type autoimmune hemolytic anemia (AIHA) that failed corticosteroid treatment. Methods:: This descriptive retrospective study included patients aged >14 years who were diagnosed with and treated for primary warm-type AIHA at the Division of Hematology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, during January 2007 to December 2016. All 54 included patients failed first-line corticosteroid treatment after which second-line treatment was prescribed. Baseline clinical characteristics, laboratory results at diagnosis and at start of second-line treatment, type of second-line treatment, treatment outcome, and complications of treatment including death were collected. Results:: Included patients had a mean age at onset of 55.8 years (14.5-87.4) and 83.3% of patients were female. Most patients (63%) were refractory to steroids, and the rest of them relapsed while on steroids. The second-line medications were azathioprine (61.1%), cyclophosphamide (31.5%), chlorambucil (1.9%), danazol (3.7%), and rituximab (1.9%), with respective response rates of 78.8%, 58.8%, 1/1 patient, 2/2 patients, and 0/1 patient. Strong positive direct Coombs' test (3+-4+) was the only predictive factor of treatment response (p = 0.008). Males had better relapse-free survival than females (not reached vs. 20.6 months) (p = 0.023). Approximately 40% of the patients who responded to second-line treatment relapsed at a median of 7.4 months. Conclusion:: Immunosuppressive drugs are the most common second-line treatment for primary warm-type AIHA in Thailand; however, relapse was common. Additional therapies are needed to reduce the relapse rate and prolong remission.

Nutraceutical and Functional Foods in Treatment of Anemia

WHO database mentions that the global anemia-affected population is 24.8%. To name a few conditions in which compromisation of the red blood corpuscles and hemoglobin occurs are iron deficiency anemia, gestational anemia, anemia due to malaria and parasitism, hemolytic anemia, sickle cell anemia. The line of treatment in case of anemia involves administration of iron supplements, plasmapheresis, steroids, blood transfusion at regular intervals, and lifestyle changes. The systematic approach applied for the pharmaceutical molecules should be equally inculcated in the case of nutraceuticals. The traditional system when woven carefully with the novel drug delivery system will give effective nutrient delivery. Functional foods have inherent nutritional value. Nutraceuticals and functional food cannot cure the anemic condition, but help the patient lead life almost like a normal individual.

Intravenous Immunoglobulin in the Treatment of Hematologic Disorders in Pediatrics

Intravenous immunoglobulin (IVIG) is pooled immunoglobulin G derived from human blood donors. It was introduced in the early 1980s to treat immunodeficiency disorders. Since then, its use has expanded to other fields such as neurology, rheumatology, and hematology. IVIG has been used to provide passive immunity in qualitative and quantitative immunoglobulin disorders, to neutralize antibodies in immune-mediated diseases, and as an immune modulatory agent. The difficulty of producing IVIG in high quantities, in addition to a growing list of "off-label" indications, has resulted in a worldwide shortage and increase in cost. From a pediatric hematology perspective, IVIG is considered an appropriate therapeutic option in autoimmune cytopenias, sometimes coadministrated with steroids. Its use in other hematologic disorders is questionable, and there is not sufficient evidence to recommend it. This article provides clear information to the general pediatrician about indications for IVIG therapy in children with hematologic disorders. [Pediatr Ann. 2017;46(1):e13-e18.].

Efficacy and safety of splenectomy in adult autoimmune hemolytic anemia

Autoimmune hemolytic anemia (AIHA) is a rare hematologic disease, primarily affecting adults or children with immunodeficiency disease. First-line therapy consists of long course of steroids administration, with an early complete response rate (CRr) of 75-80%, but up to 20-30% of patients requires a second-line therapy. Rituximab is the first choice in refractory old AIHA patients, because of its safety and efficacy (early CRr at 80-90% and at 68% at 2-3 years). For this reason, splenectomy is even less chosen as second-line therapy in elderly, even though laparoscopic technique decreased complication and mortality rates. However, splenectomy can be still considered a good therapeutic option with a CRr of 81% at 35.6 months in patients older than 60 year-old, when rituximab administration cannot be performed.

The role of rituximab in adults with warm antibody autoimmune hemolytic anemia

Warm antibody hemolytic anemia is the most common form of autoimmune hemolytic anemia. When therapy is needed, corticosteroids remain the cornerstone of initial treatment but are able to cure only a minority of patients (<20%). Splenectomy is usually proposed when a second-line therapy is needed. This classical approach is now challenged by the use of rituximab both as second-line and as first-line therapy. Second-line treatment with rituximab leads to response rates similar to splenectomy (∼70%), but rituximab-induced responses seem less sustained. However, additional courses of rituximab are most often followed by responses, at the price of reasonable toxicity. In some major European centers, rituximab is now the preferred second-line therapy of warm antibody hemolytic anemia in adults, although no prospective study convincingly supports this attitude. A recent randomized study strongly suggests that in first-line treatment, rituximab combined with steroids is superior to monotherapy with steroids. If this finding is confirmed, rituximab will emerge as a major component of the management of warm antibody hemolytic anemia not only after relapse but as soon as treatment is needed.