Warm Autoimmune Hemolytic Anemia: Clinical Profile and Management

Overall Survival and Treatment Patterns Among Patients With Warm Autoimmune Hemolytic Anemia in Sweden: A Nationwide Population-based Study

OBJECTIVES

Warm autoimmune hemolytic anemia (wAIHA) is a rare autoantibody-mediated disorder, and first-line treatment primarily relies on corticosteroids. This study assessed overall survival (OS) and treatment patterns of wAIHA in Sweden.

METHODS

Adults with ≥ 1 primary diagnosis code for wAIHA (or AIHA plus oral corticosteroids (OCS)/immunosuppressants as sensitivity analyses) between 2011 and 2022 were identified from five Swedish national registers and linked through each patient's unique identity number. Kaplan-Meier curves with log-rank tests and Cox regressions were performed to assess OS for patients with primary versus secondary wAIHA and patients with wAIHA and long-term versus short-term (≥ 3 vs. < 3 months) OCS users.

RESULTS

The main analysis included 292 patients; 1791 patients were included in the sensitivity analysis. At a median 3.7-year follow-up, a median OS in primary wAIHA was not reached versus 6.0 years for secondary wAIHA (log-rank test: p = 0.003). Subgroup analyses showed no significant difference in risk of death between long-term and short-term OCS users; however, in the sensitivity analysis, long-term OCS users showed significantly higher risk of death (adjusted hazard ratio: 1.45; 95% confidence interval: 1.180, 1.781; p < 0.001) versus short-term OCS users.

CONCLUSION

Secondary wAIHA or long-term OCS use was associated with lower OS, underscoring the disease burden and unmet need for efficacious wAIHA treatments.

Severe autoimmune hemolytic anemia; epidemiology, clinical management, outcomes and knowledge gaps

Autoimmune hemolytic anemia (AIHA) is an acquired hemolytic disorder, mediated by auto-antibodies, and has a variable clinical course ranging from fully compensated low grade hemolysis to severe life-threatening cases. The rarity, heterogeneity and incomplete understanding of severe AIHA complicate the recognition and management of severe cases. In this review, we describe how severe AIHA can be defined and what is currently known of the severity and outcome of AIHA. There are no validated predictors for severe clinical course, but certain risk factors for poor outcomes (hospitalisation, transfusion need and mortality) can aid in recognizing severe cases. Some serological subtypes of AIHA (warm AIHA with complement positive DAT, mixed, atypical) are associated with lower hemoglobin levels, higher transfusion need and mortality. Currently, there is no evidence-based therapeutic approach for severe AIHA. We provide a general approach for the management of severe AIHA patients, incorporating monitoring, supportive measures and therapeutic options based on expert opinion. In cases where steroids fail, there is a lack of rapidly effective therapeutic options. In this era, numerous novel therapies are emerging for AIHA, including novel complement inhibitors, such as sutimlimab. Their potential in severe AIHA is discussed. Future research efforts are needed to gain a clearer picture of severe AIHA and develop prediction models for severe disease course. It is crucial to incorporate not only clinical characteristics but also biomarkers that are associated with pathophysiological differences and severity, to enhance the accuracy of prediction models and facilitate the selection of the optimal therapeutic approach. Future clinical trials should prioritize the inclusion of severe AIHA patients, particularly in the quest for rapidly acting novel agents.

Autoimmune Hemolytic Anemia Following Uncomplicated Spinal Surgery: A Report and Brief Review

This report and literature review describes a case of a Coombs test-positive warm antibody autoimmune hemolytic anemia (AIHA) in a patient following routine spinal surgery without complications. This is the first reported case of symptomatic direct Coombs test-positive warm antibody AIHA developing in a neurosurgical patient. The patient is a 73-year-old female with left radicular leg pain who developed warm antibody AIHA following standard uncomplicated spinal surgery. A positive direct Coombs test confirmed the diagnosis in combination with characteristic laboratory values. The patient did not have any significant predisposing risk factors. On postoperative day (POD) 23, she presented with fatigue and characteristic laboratory values of decreased hemoglobin, elevated bilirubin, lactate dehydrogenase, and decreased haptoglobin. Hematology initiated and monitored appropriate treatment and proposed that the working hematologic diagnosis is stress-induced AIHA secondary to recent spinal surgery. The patient recovered well from a neurosurgical perspective and reported no neurosurgical complaints during the last follow-up. A female presenting with left radicular leg pain developed symptomatic anemia following uncomplicated spinal surgery. A positive direct Coombs test in combination with characteristic laboratory values confirmed the diagnosis of warm antibody AIHA.

Epidemiology of Secondary Warm Autoimmune Haemolytic Anaemia-A Systematic Review and Meta-Analysis

Background: Warm autoimmune haemolytic anaemia (wAIHA) is a haemolytic disorder, most commonly seen among adults and is classified as either primary or secondary to an underlying disease. We describe the age and sex distribution and the proportion of secondary wAIHA. Method: We retrieved 2635 published articles, screened abstracts and titles, and identified 27 articles eligible for full-text review. From these studies, we extracted data regarding number of patients, sex distribution, age at diagnosis, number of patients with secondary wAIHA, and whether the patients were diagnosed through local or referral centres. All data were weighted according to the number of included patients in each study. Results: 27 studies including a total of 4311 patients with wAIHA, of which 66% were females, were included. The median age at diagnosis was 68.7 years, however, wAIHA affected all ages. The mean proportion of secondary wAIHA was 49%, most frequently secondary to systemic lupus erythematosus. The proportions of secondary wAIHA reported from primary vs. referral centres were 35% vs. 59%, respectively. Conclusion: This review consolidates previously reported gender distribution. The higher proportion of secondary wAIHA in referral centres suggests that the most severely affected patients are disproportionally more frequent in such facilities.

A 34-year-old Japanese patient exhibiting NBAS deficiency with a novel mutation and extended phenotypic variation

Biallelic neuroblastoma amplified sequence (NBAS) gene mutations have recently been identified to cause a reduction in its protein expression and a broad phenotypic spectrum, from isolated short stature, optic nerve atrophy, and Pelger-Huët anomaly (SOPH) syndrome or infantile liver failure syndrome 2 to a combined, multi-systemic disease including skeletal dysplasia and immunological and neurological abnormalities. Herein, we report a 34-year-old patient with a range of phenotypes for NBAS deficiency due to compound heterozygous variants; one is a SOPH-specific variant, p.Arg1914His, and the other is a novel splice site variant, c.6433-2A>G. The patient experienced recurrent acute liver failure until early childhood. Hypogammaglobulinemia, a decrease in natural killer cells, and optic nerve atrophy were evident from infancy to childhood. In adulthood, the patient exhibited novel phenotypic features such as hepatic cirrhosis complicated by portal hypertension and autoimmune hemolytic anemia. The patient also suffered from childhood-onset insulin-requiring diabetes with progressive beta cell dysfunction. The patient had severe short stature and exhibited dysmorphic features compatible with SOPH, intellectual disability, and epilepsy. NBAS protein expression in the patient's fibroblasts was severely low. RNA expression analysis for the c.6433-2A>G variant showed that this variant activated two cryptic splice sites in intron 49 and exon 50, for which the predicted consequences at the protein level were an in-frame deletion/insertion, p.(Ile2199_Asn2202delins16), and a premature termination codon, p.(Ile2199Tyrfs*17), respectively. These findings indicate that NBAS deficiency is a multi-systemic progressive disease. The results of this study extend the spectrum of clinical and genetic findings related to NBAS deficiency.

Clinical Profile and Severity of Hemolysis in Adult Patients of Primary Autoimmune Hemolytic Anemia and Their Response to Steroid: A Prospective Cohort Study from Single Institution

Autoimmune hemolytic anaemia (AIHA) has traditionally been classified based on the temperature sensitivity of the autoagglutinins as warm (WAIHA), cold (CAIHA) and mixed type. Autoagglutinin may be of IgG or IgM type. The present prospective study was conducted to evaluate the profile of clinical picture, severity of haemolysis, treatment response of steroid. This study on patients of adult primary AIHA was conducted by taking complete history followed by detail physical examination. Laboratory investigations were performed to establish haemolytic anaemia and to assess severity of haemolysis. Immunehematological work up including blood grouping, direct antiglobulin test (DAT), IAT, antibody screening, adsorption elution was performed to diagnose type of AIHA. All cases were followed up to assess the response to prednisolone. All the data were collected and analysed by SPSS 19. Out of 62 primary AIHA cases, female were affected more than male (41:21). WAIHA is most common type (42, 67.8%) followed by mixed (20.9%) and cold AIHA (11.3%). Severity of haemolysis showed significant correlation with the DAT strength and not with type of AIHA. (P < 0.05) On oral prednisolone, 22 cases attended complete remission, while relapse, drug dependency and partial remission was achieved in 13, 9, 3 cases respectively. Severity of haemolysis in AIHA is directly related with DAT strength. WAIHA is most common type and can be managed with oral prednisolone (cr 45.2%), without red cell transfusion in most of cases. Mixed type AIHA cases were presented mostly with severe haemolysis, with minimum therapeutic response to prednisolone and maximum relapse/drug dependency.