The role of splenectomy in autoimmune hematological disorders: Outdated or still worth considering?

The Role of the Spleen and the Place of Splenectomy in Autoimmune Hemolytic Anemia-A Review of Current Knowledge

Autoimmune hemolytic anemia (AIHA) is a rare, very heterogeneous, and sometimes life-threatening acquired hematologic disease characterized by increased red blood cell (RBC) destruction by autoantibodies (autoAbs), either with or without complement involvement. Recent studies have shown that the involvement of T- and B-cell dysregulation and an imbalance of T-helper 2 (Th2) and Th17 phenotypes play major roles in the pathogenesis of AIHA. AIHA can be primary (idiopathic) but is more often secondary, triggered by infections or drug use or as a part of other diseases. As the location of origin of autoAbs and the location of autoAb-mediated RBC clearance, as well as the location of extramedullary hematopoiesis, the spleen is crucially involved in all the steps of AIHA pathobiology. Splenectomy, which was the established second-line therapeutic option in corticosteroid-resistant AIHA patients for decades, has become less common due to increasing knowledge of immunopathogenesis and the introduction of targeted therapy. This article provides a comprehensive overview of current knowledge regarding the place of the spleen in the immunological background of AIHA and the rapidly growing spectrum of novel therapeutic approaches. Furthermore, this review emphasizes the still-existing expediency of laparoscopic splenectomy with appropriate perioperative thromboprophylaxis and the prevention of infection as a safe and reliable therapeutic option in the context of the limited availability of rituximab and other novel therapies.

NMR-Based Metabolomics Identify Metabolic Change in Spleen of Idiopathic Thrombocytopenic Purpura Patients

Idiopathic thrombocytopenic purpura (ITP) is a common hematological disease and the abnormal platelet destruction in the spleen is a critical pathological mechanism for ITP. However, the metabolomic change in the spleen caused by ITP is still unclear. In the present study, the metabolomic information of 18 ITP and 20 normal spleen samples were detected by using ¹H high-resolution magic angle spinning NMR spectroscopy (¹H MAS NMR). Compared with normal spleen, the concentrations of acetate, alanine, glutamine, glycerol, isoleucine, lysine, valine, phenylalanine, leucine, and methanol in ITP spleen tissue were elevated and 3-hydroxybutyric acid, ascorbate, asparagine, ethanol, glycogen, low-density lipoprotein, malonate, myo-inositol, glycerophosphocholine, pyroglutamate, and taurine were decreased. Amino acids metabolic pathways, such as branched-chain amino acids pathway, were identified as the main involved pathways based on enrichment analysis. The decrease in taurine level in the spleen was the most obvious metabolic signature involving ITP with high sensitivity and specificity to distinguish the spleen of ITP from the normal (CI: 0.825–0.982). Notably, the level of taurine in the spleen was negatively correlated with the efficacy of splenectomy (r = 0.622, p = 0.006). Collectively, the data from our study revealed previously unknown ITP-related metabolomic changes in the spleen and found a potential diagnostic and efficacy-predictive biomarker for ITP treatment.

Evaluating fostamatinib disodium as a treatment option for immune thrombocytopenia in adult patients

INTRODUCTION

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder characterized by increased platelet destruction and decreased platelet production, leading to thrombocytopenia with or without bleeding manifestations. The majority of patients experiencing treatment need will eventually need secondary treatment following first line therapy with steroids. In 2018, the oral spleen tyrosine kinase inhibitor fostamatinib received US Food and Drug Administration approval for ITP patients with an insufficient response to a previous treatment.

AREAS COVERED

This review outlines pharmacological characteristics of fostamatinib and provides an overview of its efficacy and safety results in phase II and III trials, followed by the expert opinion of the authors.

EXPERT OPINION

Increasing knowledge on the role of different players and mechanisms in the pathophysiology of autoimmune disorders in general and of ITP in particular, has led to the development of several new treatment options, as illustrated by the introduction of fostamatinib in the treatment of ITP. However, lacking direct comparison with other recent treatment options (in particular thrombopoietin receptor agonists), its use should be evaluated critically taking into account the unique toxicity and potential drug-drug interaction profile.

Clinical and surgical outcomes of splenectomy for autoimmune hemolytic anemia

INTRODUCTION

We investigated short and long-term remission rates after splenectomy in patients with primary and secondary autoimmune hemolytic anemia (AIHA).

METHODS

All adults who underwent splenectomy for primary or secondary AIHA at a single center (2004-2018) were retrospectively reviewed. Short-term response was determined at 30-day postoperatively and long-term at one year. Complete response was defined as hemoglobin > 10 g/dL without hemolysis, transfusions, or need for additional medical therapy for > 6 months.

RESULTS

Short-term complete response was attained in 22 of 36 patients (61%), partial response in 3 (8%), no response in 11 (31%). The response rate at 1 year was complete in 14/36 (39%), partial in 14 (39%), and 8 non-response (22%). At last available follow-up (median 33.1 months (IQR 19-59), 16/37 patients had experienced a complete response (43%), 14 partial response (38%), 7 non-response (19%). 80% of partial responders with primary AIHA required maintenance therapy compared to 100% with secondary AIHA.

CONCLUSION

Splenectomy is associated with short- and long-term improvement in anemia and hemolysis in the majority of patients with AIHA. Immunosuppressants remain important supplemental therapy.

Update on diagnosis and treatment of immune thrombocytopenia

BACKGROUND

Immune thrombocytopenia (ITP) is a heterogeneous acquired disorder characterized by isolated thrombocytopenia whose exact pathogenesis is not yet clear. Depending upon the presence or absence of an underlying treatable cause, ITP can be categorized as primary or secondary. Primary ITP is a diagnosis of exclusion and there is no gold standard test for its confirmation. Recent drug intake, infections, lymphoproliferative disorders, and connective tissue disorders should be ruled out before labeling a patient as primary ITP.

AREA COVERED

This review summarizes a comprehensive update on the diagnostic and therapeutic modalities for ITP. We reviewed the literature using GOOGLE SCHOLAR, PUBMED and ClinicalTrial.gov databases as needed to support the evidence. We searched the literature using the following keywords: 'immune thrombocytopenia,' 'idiopathic thrombocytopenic purpura,' 'thrombocytopenia,' 'immune thrombocytopenic purpura,' and 'isolated thrombocytopenia'.

EXPERT OPINION

We believe that more detailed studies are required to understand the exact pathophysiology behind ITP. The first-line drugs like corticosteroids have both short-term and long-term adverse effects. This brings the need to explore effective alternative medications and to reconsider their role in ITP treatment algorithm if guidelines can be modified based on new studies.

Treating thrombotic thrombocytopenic purpura without plasma exchange during the COVID-19 pandemic. A case report and a brief literature review

We report the case of a patient diagnosed with a clinical relapse of acquired immune-mediated thrombotic thrombocytopenic purpura (TTP) who was successfully treated with low-dose rituximab plus corticosteroids without the use of plasma exchange (PEx), which was unavailable at the time due to the COVID-19 pandemic. Rituximab 100 mg weekly for 4 weeks was administered, combined with 1 mg/kg of prednisone, obtaining a complete hematological response in 6 weeks. This case suggests that PEx may be unnecessary for a subset of patients with relapsed TTP who are clinically stable without significant end-organ damage. A brief literature review regarding TTP patients treated without plasma exchange is also included.

Autoimmune hemolytic anemia: current knowledge and perspectives

Autoimmune hemolytic anemia (AIHA) is an acquired, heterogeneous group of diseases which includes warm AIHA, cold agglutinin disease (CAD), mixed AIHA, paroxysmal cold hemoglobinuria and atypical AIHA. Currently CAD is defined as a chronic, clonal lymphoproliferative disorder, while the presence of cold agglutinins underlying other diseases is known as cold agglutinin syndrome. AIHA is mediated by autoantibodies directed against red blood cells (RBCs) causing premature erythrocyte destruction. The pathogenesis of AIHA is complex and still not fully understood. Recent studies indicate the involvement of T and B cell dysregulation, reduced CD4+ and CD25+ Tregs, increased clonal expansions of CD8 + T cells, imbalance of Th17/Tregs and Tfh/Tfr, and impaired lymphocyte apoptosis. Changes in some RBC membrane structures, under the influence of mechanical stimuli or oxidative stress, may promote autohemolysis. The clinical presentation and treatment of AIHA are influenced by many factors, including the type of AIHA, degree of hemolysis, underlying diseases, presence of concomitant comorbidities, bone marrow compensatory abilities and the presence of fibrosis and dyserthropoiesis. The main treatment for AIHA is based on the inhibition of autoantibody production by mono- or combination therapy using GKS and/or rituximab and, rarely, immunosuppressive drugs or immunomodulators. Reduction of erythrocyte destruction via splenectomy is currently the third line of treatment for warm AIHA. Supportive treatment including vitamin supplementation, recombinant erythropoietin, thrombosis prophylaxis and the prevention and treatment of infections is essential. New groups of drugs that inhibit immune responses at various levels are being developed intensively, including inhibition of antibody-mediated RBCs phagocytosis, inhibition of B cell and plasma cell frequency and activity, inhibition of IgG recycling, immunomodulation of T lymphocytes function, and complement cascade inhibition. Recent studies have brought about changes in classification and progress in understanding the pathogenesis and treatment of AIHA, although there are still many issues to be resolved, particularly concerning the impact of age-associated changes to immunity.

[Ibrutinib treatment for 2 cases of relapsed/refractory autoimmune hemolytic anemia: a pilot study]

Objective: To explore the efficacy and safety of ibrutinib treatment for relapsed/refractory (R/R) primary autoimmune hemolytic anemia (AIHA) . Methods: Two cases of primary AIHA with relapse events were refractory to glucocorticoid, anti-CD20 monoclonal antibody, immunosuppressive drugs, and splenectomy (case 1 only) . Ibrutinib treatment was administered at an initial dose of 280 mg/d (420 mg/d for case 1 from the 3rd to 8th week) . Results: Both patients achieved transfusion independence and HGB>20 g/L above baseline after 2 weeks (partial response) . For case 1, HGB concentration restored to 113 g/L but with incomplete hemolysis recovery after 10 weeks; HGB reached the level of 118 g/L, also with incomplete hemolysis recovery, after 6 weeks in case 2. They all acquired complete response with incomplete hemolysis recovery (CRi) . The responses sustained 14 weeks and 10 weeks after follow-up at 16 weeks and 12 weeks, respectively. During the treatment, hematologic and nonhematologic toxicity is mild and acceptable. Conclusion: Ibrutinib alone is effective for the 2 R/R primary AIHA cases. We need further clinical trial to identify its efficacy and safety.

Second-line treatment trends and long-term outcomes of 392 children with chronic immune thrombocytopenic purpura: the French experience over the past 25 years

Childhood chronic immune thrombocytopenic purpura (cITP) is a rare disease. In severe cases, there is no evidence for the optimal therapeutic strategy. Our aim was to describe the real-life management of non-selected children with cITP at diagnosis. Since 2004, patients less than 18 years old with cITP have been enrolled in the national prospective cohort, OBS'CEREVANCE. From 1990 to 2014, in 29 centres, 392 children were diagnosed with cITP. With a median follow-up of six years (2·0-25), 45% did not need second-line therapy, and 55% (n = 217) received one or more second lines, mainly splenectomy (n = 108), hydroxychloroquine (n = 61), rituximab (n = 61) or azathioprine (n = 40). The overall five-year further second-line treatment-free survival was 56% [95% CI 49·5-64.1]. The use of splenectomy significantly decreased over time. Hydroxychloroquine was administered to children with positive antinuclear antibodies, more frequently older and girls, and reached 55% efficacy. None of the patients died. Ten years after the initial diagnosis, 55% of the 56 followed children had achieved complete remission. Children with cITP do not need second-line treatments in 45% of cases. Basing the treatment decision on the pathophysiological pathways is challenging, as illustrated by ITP patients with positive antinuclear antibodies treated with hydroxychloroquine.

Splenectomy and the incidence of venous thromboembolism and sepsis in patients with autoimmune hemolytic anemia

INTRODUCTION

The impact of splenectomy on venous thrombosis (VTE), abdominal thrombosis (abVTE) and sepsis in autoimmune hemolytic anemia (AIHA) is unclear.

METHODS

Using the California Discharge Dataset 1991-2014, 4756 AIHA patients were identified. Cumulative incidences (CI) of VTE, abVTE, and sepsis were determined in patients with and without splenectomy. Using propensity score matching adjusted for competing risk of death, the association between VTE, abVTE and sepsis with splenectomy was determined.

RESULTS

In those without splenectomy, the CIs of VTE, abVTE, and sepsis were 1.4%, 0.2%, and 4.3% respectively, compared to 4.4%, 3.0% and 6.7% with splenectomy. Splenectomy was associated with increased risk for VTE in immediate (HR 2.66, CI 1.36-5.23) and late (HR 3.29, CI 2.10-5.16) post-operative periods. AbVTE was increased in immediate post-operative period (HR 34.11, CI 4.93-236.11). Sepsis was only increased in late post-operative period (HR 2.20, CI 1.75-2.77). In multivariate models, older age, having >1 comorbidity and having VTE, abVTE, and sepsis were associated with increased mortality. Splenectomy was not associated with increased mortality.

DISCUSSION

Splenectomy in AIHA was associated with significant early thrombotic risk and long-term morbidity. Future research should evaluate the role of splenectomy in AIHA patients, and potential long-term thrombotic and antibiotic prophylaxis.

Long-term remission rates after splenectomy in adults with Evans syndrome compared to immune thrombocytopenia: A single-center retrospective study

OBJECTIVE

Evans syndrome, the combination of immune thrombocytopenia (ITP) and autoimmune hemolytic anemia (AIHA) or autoimmune neutropenia, is associated with a high rate of relapsed/refractory disease. There are limited data on the efficacy of splenectomy for this condition. We reviewed patient outcomes after splenectomy for Evans syndrome compared to ITP at our institution.

METHODS

We performed a retrospective analysis of patients who underwent splenectomy for autoimmune cytopenias over a 23-year period with the intention of comparing disease relapse rates after splenectomy in patients with Evans syndrome and in those with ITP.

RESULTS

During the study period, 77 patients underwent splenectomy for ITP and seven underwent splenectomy for Evans syndrome. In the Evans cohort, splenectomy led to an 85.7% initial response rate with a 42.8% rate of relapse within one year and a long-term (one-year) response rate of 42.8%. In the ITP cohort, the initial response rate was 90.9% with a long-term response rate of 70.1%.

CONCLUSION

Our data suggest that long-term remission rates after splenectomy are lower in adults with Evans syndrome compared to those with ITP, although splenectomy may still be an acceptable treatment for certain patients with Evans syndrome. Our findings underscore the need for further research and development of additional therapeutic strategies for this patient population.

Treatment of autoimmune hemolytic anemia: real world data from a reference center in Mexico

Background

Warm autoimmune hemolytic anemia (w-AIHA) is an uncommon disease with heterogeneous response to treatment. Steroids are the standard treatment at diagnosis, whereas rituximab has recently been recommended as the second-line therapy of choice. Our main objective was to document the response to treatment in patients with newly diagnosed w-AIHA, including the effectiveness of low-dose rituximab as frontline treatment and for refractory disease.

Methods

Patients with w-AIHA from 2002 to 2017 were included. Relapse-free survival (RFS), probability of maintained response (MR), and time-to-response were analyzed using the Kaplan–Meier method. Response was classified as complete, partial, and no response.

Results

We included 64 adults with w-AIHA (39 women and 25 men). The median age was 37 (16–77) years. Response rates to steroids alone were 76.7%, rituximab plus steroids, 100%; and cyclophosphamide, 80%. RFS with steroids at 6, 36, and 72 months was 86.3%, 65.1%, and 59.7%, respectively. Eighteen patients received rituximab at 100 mg/wk for 4 weeks plus high-dose dexamethasone as first-line therapy, with RFS at 6, 36, and 72 months of 92.3%, 58.7% and 44.1%, respectively. Eight patients refractory to several lines of therapy were treated with low-dose rituximab, and all achieved a response (three complete response and five partial response) at a median 16 days (95% confidence interval, 14.1–17.8), with a 75% probability of MR at 103 months; the mean MR was 81.93±18 months.

Conclusion

Outcomes of w-AIHA treatment were considerably heterogeneous. Low rituximab doses plus high dexamethasone doses were effective for refractory disease.

Proposal of treatment algorithm for immune thromocytopenia in adult patients of a hematology service at a referral center in Northeastern Brazil

Introduction

The management of adult (≥18 years) immune thrombocytopenia patients relies on platelet count, the risk of bleeding and presence of bleeding.

Objective

Confirming the diagnosis of immune thrombocytopenia and the start of therapy, our hematology service, a referral center, favors the establishment of this algorithm to treat those patients.

Results

Presentation, recently diagnosed or recurrence – group 1: life-threatening bleeding: high-dose intravenous immunoglobulins with methylprednisolone or dexamethasone. Hospitalization and platelet transfusion are considered. Group 2: Platelets <30 × 10⁹/L with bleeding or risk factor for bleeding, or platelets <20 × 10⁹/L: prednisone or dexamethasone. No response, platelets <20 × 10⁹/L: replace corticoid or increase doses. If platelets continue <20 × 10⁹/L: immunization and splenectomy. Investigation of Helicobacter pylori, if positive: treatment for H. pylori. Chronic immune thrombocytopenia with platelets <20 × 10⁹/L we propose two new groups (A and B): Group A: <65 years, no or low surgical risk, patient declines maintenance therapy or patient intends to get pregnant: immunization and splenectomy. Group B: failure of splenectomy (refractory) or no splenectomy indication or history of exposure to malaria or babesiosis and no response to corticoids or corticoid dependence: choose thrombopoietin receptor agonists: eltrombopag or romiplostim. Patient at high risk for arterial or venous thrombosis: recommend rituximab. After rituximab or thrombopoietin receptor agonists, if platelets continue <20 × 10⁹/L: indicate immunosuppressants (azathioprine or cyclophosphamide), dapsone or mycophenolate mofetil or vinca alkaloids. The goals of treatment for chronic or refractory immune thrombocytopenia are to keep platelets >20 × 10⁹/L and stop bleeding.