Rituximab therapy for autoimmune haematological diseases

Systemic loxoscelism induced warm autoimmune hemolytic anemia: clinical series and review

OBJECTIVES

Describe the development of warm autoimmune hemolytic anemia warm (AIHA) secondary to a brown recluse spider (Loxosceles reclusa) bite is known as systemic loxoscelism; and review epidemiology, clinical manifestations, diagnostic work-up, pathophysiology, and treatment options associated with warm AIHA secondary to systemic loxoscelism.

METHODS

Cases series of two cases of warm AIHA due to systemic loxoscelism and a review of the current literature: epidemiology, clinical manifestations, diagnostic work-up, pathophysiology, and treatment options associated with warm AIHA secondary to systemic loxoscelism.

RESULTS

Presented here are two cases of warm AIHA due to systemic loxoscelism. Each patient was generally healthy appearing and presented with symptomatic anemia in the setting of brown recluse spider bites. Both patients were eventually found to have warm AIHA. Upon recognition of the diagnosis, the patients were started on corticosteroids and aggressive intravenous fluid hydration. In addition, they received transfusions of packed red blood cells. Their clinical courses improved, and they recovered to eventually be discharged home.

CONCLUSION

Envenomation by a brown recluse spider, Loxosceles reclusa, can result in systemic loxoscelism which can cause warm AIHA. The diagnosis of warm AIHA is confirmed by the direct antiglobulin/Coomb's test. Warm AIHA can be a life-threatening disease process. Hemodynamic support with intravenous fluids and RBC transfusion is the initial step in the management of these patients. Corticosteroids are the mainstay of current management. Second line treatments include rituximab. Rarely patients require splenectomy for refractory disease. Corticosteroids should be tapered over a three-month period.

ABO subgroup incompatibility with severe hemolysis after consecutive allogeneic stem cell transplantations

Allogeneic hematopoietic stem cell transplantations (HSCTs) represent a curative strategy for treating hematologic malignancies yet bear dangerous and frequently life‐threatening complications including the development of graft‐versus‐host disease. Here, we present a case of a patient that suffered from relapsed/refractory multiple myeloma, a hematologic neoplasm characterized by clonal proliferation of malignant plasma cells in the bone marrow. During the course of his disease, the patient underwent consecutive allogeneic HSCTs, during which he developed a clinical meaningful and hitherto unreported ABO subgroup incompatibility, leading to persistent hemolysis. Testing for ABO subgroups during donor selection, especially after consecutive allogeneic HSCTs, may therefore aid to prevent these complications.

Rituximab Use in Warm and Cold Autoimmune Hemolytic Anemia

Autoimmune hemolytic anemia is a rare condition characterized by destruction of red blood cells with and without involvement of complement. It is associated with significant morbidity and mortality. In warm autoimmune hemolytic anemia, less than 50% of patients remain in long-term remission following initial steroid therapy and subsequent therapies are required. Cold agglutinin disease is a clonal hematologic disorder that requires therapy in the majority of patients and responds poorly to steroids and alkylators. Rituximab has a favorable toxicity profile and has demonstrated efficacy in autoimmune hemolytic anemia in first-line as well as relapsed settings. Rituximab is the preferred therapy for steroid refractory warm autoimmune hemolytic anemia (wAIHA) and as part of the first- and second-line treatment of cold agglutinin disease. This article reviews the mechanism of action of rituximab and the current literature on its role in the management of primary and secondary warm autoimmune hemolytic anemia and cold agglutinin disease.

Nanomedicines: A Potential Treatment for Blood Disorder Diseases

Blood disorder diseases (BDDs), also known as hematologic, is one of the diseases owing to hematopoietic system disorder. Chemotherapy, bone marrow transplantation, and stem cells therapy have been used to treat BDDs. However, the cure rates are still low due to the availability of the right type of bone marrow and the likelihood of recurrence and infection. With the rapid development of nanotechnology in the field of biomedicine, artificial blood or blood substitute has shown promising features for the emergency treatment of BDDs. Herein, we surveyed recent advances in the development of artificial blood components: gas carrier components (erythrocyte substitutes), immune response components (white blood cell substitutes), and hemostasis-responsive components (platelet substitutes). Platelet-inspired nanomedicines for cancer treatment were also discussed. The challenges and prospects of these treatment options in future nanomedicine development are discussed.

Autoimmune hemolytic anemia, autoimmune neutropenia and aplastic anemia in the elderly

The physiology of the immune system involves morphologic and functional changes occurring along ageing, with a decrease in immune response and an increase in autoimmune phenomena, even in the absence of overt disese. Autoimmune cytopenias, namely autoimmune hemolytic anemia (AIHA), chronic idiopathic neutropenia (CIN) and aplastic anemia (AA), show different epidemiologic predilection, but are increasingly diagnosed in the elderly, where complications and comorbidities are more frequent. A systematic review of recent literature, shows that comorbidities as well as underlying deficiencies, medications, neoplasms, and, pathophysiologic chronic organ failures, frequently challenge the differential diagnosis in this setting and should always be evaluated and excluded. Complications, particularly infections and thrombosis for AIHA, and bleeding for AA, should be monitored and promptly treated. Treatment choice should be carefully weighed on the individual general condition and comorbidities, granted that intense primary care and support (including evidence-based transfusion policies) are provided. Finally, bone marrow histology is highly advisable in the elderly, both at diagnosis to detect underlying conditions, and along the follow-up to monitor possible bone marrow failure or neoplastic evolution.

Current and emerging treatment options for autoimmune hemolytic anemia

INTRODUCTION

Autoimmune hemolytic anemia (AIHA) is a heterogeneous disease mainly due to autoantibody-mediated destruction of erythrocytes but also involves complement activation, dysregulation of cellular and innate immunity, and defective bone marrow compensatory response. Several drugs targeting these mechanisms are under development in addition to standard therapies. Areas covered: The following targeted therapies are illustrated: drugs acting on CD20 (rituximab, alone or in association with bendamustine and fludarabine) and CD52 (alemtuzumab), B cell receptor and proteasome inhibitors (ibrutinib, bortezomib), complement inhibitors (eculizumab, BIVV009, APL-2), and other drugs targeting T lymphocytes (subcutaneous IL-2, belimumab, and mTOR inhibitors), IgG driven extravascular hemolysis (fostamatinib), and bone marrow activity (luspatercept). Expert opinion: Although AIHA is considered benign and often easy to treat, chronic/refractory cases represent a challenge even for experts in the field. Bone marrow biopsy is fundamental to assess one of the main mechanisms contributing to AIHA severity, i.e. inadequate compensation, along with lymphoid infiltrate, the presence of fibrosis or dyserythropoiesis. The latter may give hints for targeted therapies (either B or T cell directed) and for new immunomodulatory drugs. Future studies on the genomic landscape in AIHA will further help in designing the best choice, sequence and/or combination of targeted therapies.

Copper-associated hepatitis in a patient with chronic myeloid leukemia following hematopoietic stem cell transplantation: A case report

RATIONALE

We report a complicated case of cholestatic hepatitis with suspected autoimmune hemolytic anemia (AIHA) and copper toxicity syndrome after HSCT and donor lymphocyte infusion (DLI).

PATIENT CONCERNS

A 19-year-1-month-old girl presented with a history of CML. She underwent matched unrelated donor HSCT and donor lymphocyte infusion subsequently. Three months later, yellowish discoloration of the skin was found, which was accompanied by progressive itchy skin, easy fatigability, insomnia, and dark urine output. After admission, liver function disorders were observed.

INTERVENTION

Methylprednisolone was administered for suspected hepatic GVHD. Although abdominal sonography revealed no evidence of biliary tract obstruction and the viral hepatitis survey disclosed unremarkable findings; silymarin and ursodeoxycholic acid were administered to preserve the liver function. In addition, rituximab was prescribed for suspected AIHA. Because hyperbilirubinemia was progressive, mycophenolate and high-dose intravenous immunoglobulin were accordingly administered. As drug-induced liver injury cannot be excluded, all potential unconfirmed causes of drug-related hepatoxicity were discontinued.

DIAGNOSIS

In this case, the patient's history of shrimps and chocolate consumption led us to strongly suspect cholestatic hepatitis associated with copper toxicity syndrome. High 24-hour urine copper excretion and low serum zinc levels were also confirmed. Accordingly, D-penicillamine and zinc gluconate were administered.

OUTCOMES

She succumbed to progressive hepatic failure and eventual multisystem organ failure 14 months after HSCT. No autopsy was performed.

LESSONS

This report described the combined effects of hepatic GVHD, AIHA, drugs, and copper toxicity on liver damage, and demonstrated the potential diagnostic challenges and treatment dilemmas associated with this disease.

Success of anti-CD20 monoclonal antibody treatment for severe autoimmune hemolytic anemia caused by warm-reactive immunoglobulin A, immunoglobulin G, and immunoglobulin M autoantibodies in a child: a case report

Background

Autoimmune hemolytic anemia is rare in children. First-line therapies for this disease consist of corticosteroids and intravenously administered immunoglobulin that are effective in most patients. However, a small proportion of cases (5 to 10%) is refractory to these therapies and may represent a medical emergency, especially when hemolysis is due to warm immunoglobulin M. Recently, reports of the use of rituximab in adult autoimmune diseases have shown promising results. In children, there are few studies on the use of rituximab in the treatment for autoimmune hemolytic anemia, especially on its long-term efficacy and adverse effects.

Case presentation

Here, we report the case of a 10-year-old Tunisian girl with refractory acute autoimmune hemolytic anemia caused by warm-reactive immunoglobulin A, immunoglobulin G, immunoglobulin M, and C3d autoantibodies. First-line treatments using corticosteroids and intravenously administered immunoglobulin were ineffective in controlling her severe disease. On the other hand, she was successfully treated with rituximab. In fact, her hemolytic anemia improved rapidly and no adverse effects were observed.

Conclusions

The case that we report in this paper shows that rituximab could be an alternative therapeutic option in severe acute autoimmune hemolytic anemia with profound hemolysis refractory to conventional treatment. Moreover, it may preclude the use of plasmapheresis in such an urgent situation with a sustained remission.

Natural History, Pathogenesis, and Treatment of Evans Syndrome in Children

Primary Evans syndrome (ES) is defined by the concurrent or sequential occurrence of immune thrombocytopenia and autoimmune hemolytic anemia in the absence of an underlying etiology. The syndrome is characterized by a chronic, relapsing, and potentially fatal course requiring long-term immunosuppressive therapy. Treatment of ES is hardly evidence-based. Corticosteroids are the mainstay of therapy. Rituximab has emerged as the most widely used second-line treatment, as it can safely achieve high response rates and postpone splenectomy. An increasing number of new genetic defects involving critical pathways of immune regulation identify specific disorders, which explain cases of ES previously reported as "idiopathic".

Rituximab prophylaxis to prevent thrombotic thrombocytopenic purpura relapse: outcome and evaluation of dosing regimens

Acute antibody-mediated thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy with high morbidity and mortality. Rituximab is highly effective as prophylaxis in patients at risk of acute TTP relapse, but the ideal dosing regimen is unknown. A multicenter retrospective cohort study evaluated outcomes of patients given rituximab prophylaxis to prevent TTP relapse. Rituximab was given in 76 episodes to 45 patients (34 women and 11 men). Four once-per-week infusions of standard- (375 mg/m² [24 episodes]), reduced- (200 mg [19 episodes]), and intermediate- (500 mg [17 episodes]) dose rituximab were given; in the remaining 16 episodes, patients received 100 to 1000 mg rituximab in 1 to 5 doses. Patients were deemed at high risk of TTP relapse on the basis of ADAMTS13 activity dropping to ≤15% from the normal range. Preprophylaxis median ADAMTS13 level was 5% (range, <5% to 17%). Normalization of ADAMTS13 occurred in 78.9% of patients, with 92.1% having at least a partial response (ADAMTS13 ≥30%); 3 patients had no response. Over a median of 15 months (range, 1-141 months), there were only 3 TTP relapses (2 of these subacute) in the reduced dose group. Re-treatment with rituximab occurred in 50% of patient episodes at a median of 17.5 months (range, 9-112 months) after initial prophylaxis. There was a statistically higher rate of re-treatment in the reduced- vs standard-dose group: 0.38 vs 0.17 episodes per year, respectively. Treatment was generally well tolerated, infusional effects being the most commonly reported. Rituximab therapy is effective as prophylaxis for normalizing ADAMTS13 and is an additional measure for preventing acute TTP relapses in patients with immune TTP.

Broad Concepts in Management of Systemic Lupus Erythematosus

Systemic lupus erythematosus is a multisystem autoimmune disease with protean manifestation. Although commonly seen in young women, it can affect men as well as elderly patients. Approach to treatment is multidisciplinary, involves defining the extent of organ involvement, and distinguishing between active manifestations and damage. The mainstay of therapy is judicious use of immunosuppressive medications. Long-term follow-up to address morbidity arising from treatment complications, disease damage, and increased cardiovascular risk is essential.

Rituximab in the treatment of autoimmune haemolytic anaemia

Rituximab is a B-cell depleting monoclonal antibody that is gaining popularity as an effective therapy for many autoimmune cytopenias. This article systematically evaluates its therapeutic efficacy in the treatment of different types of autoimmune haemolytic anaemia. We conclude that there is sufficient evidence to recommend it as a second line therapy for warm autoimmune haemolytic anaemia (wAIHA) either as monotherapy or combined therapy. Evidence from a single randomized controlled trial suggests that it may also be more efficacious as first line therapy in combination with steroids than steroids alone. A fewer number of studies have assessed its role in cold autoimmune haemolytic anaemia (cAIHA) and cold agglutinin disease (CAD) with success rates varying from 45-66%. In the absence of alternative definitive therapy, rituximab should be considered for patients with symptomatic CAD and significant haemolysis. Case reports of its efficacy in mixed autoimmune haemolytic anaemias are available but evidence from case series or larger cohorts are nonexistent.

Clinical Applications of Hemolytic Markers in the Differential Diagnosis and Management of Hemolytic Anemia

Several hemolytic markers are available to guide the differential diagnosis and to monitor treatment of hemolytic conditions. They include increased reticulocytes, an indicator of marrow compensatory response, elevated lactate dehydrogenase, a marker of intravascular hemolysis, reduced haptoglobin, and unconjugated hyperbilirubinemia. The direct antiglobulin test is the cornerstone of autoimmune forms, and blood smear examination is fundamental in the diagnosis of congenital membrane defects and thrombotic microangiopathies. Marked increase of lactate dehydrogenase and hemosiderinuria are typical of intravascular hemolysis, as observed in paroxysmal nocturnal hemoglobinuria, and hyperferritinemia is associated with chronic hemolysis. Prosthetic valve replacement and stenting are also associated with intravascular and chronic hemolysis. Compensatory reticulocytosis may be inadequate/absent in case of marrow involvement, iron/vitamin deficiency, infections, or autoimmune reaction against bone marrow-precursors. Reticulocytopenia occurs in 20–40% of autoimmune hemolytic anemia cases and is a poor prognostic factor. Increased reticulocytes, lactate dehydrogenase, and bilirubin, as well as reduced haptoglobin, are observed in conditions other than hemolysis that may confound the clinical picture. Hemoglobin defines the clinical severity of hemolysis, and thrombocytopenia suggests a possible thrombotic microangiopathy or Evans' syndrome. A comprehensive clinical and laboratory evaluation is advisable for a correct diagnostic and therapeutic workup of the different hemolytic conditions.

The anti-CD20 monoclonal antibody rituximab to treat acquired haemophilia A

BACKGROUND

Acquired haemophilia A (AHA) is a rare bleeding disorder caused by the development of specific autoantibodies against naturally occurring factor VIII (FVIII). Although about half of cases are idiopathic, AHA may be associated with several non-neoplastic conditions, autoimmune disorders, as well as haematological malignancies, such as chronic lymphocytic leukaemia and lymphoma. The long-term suppression of inhibitors is one of the mainstays of the treatment of AHA. Apart from standard immunosuppressive treatments, rituximab has been proven to be effective in AHA.

MATERIALS AND METHODS

The aim of this review is to provide a systematic description of data available in the literature on this topic. To do so, we performed a search using the indexed online database Medline/PubMed, without temporal limits, matching the words "rituximab" and "acquired h(a)emophilia". Furthermore, additional published studies were identified in the reference list of the publications found in PubMed.

RESULTS

The review of the literature confirms that rituximab may be a safe and useful treatment for AHA.

DISCUSSION

Although rituximab is not a standard therapy for AHA, it may be useful in resistant cases. However, the definitive place of this monoclonal antibody in the therapeutic strategy for AHA (first or second-line, alone or in combination with other drugs) remains to be determined more precisely and warrants further investigation.

Treatment of autoimmune hemolytic anemias

Autoimmune hemolytic anemia (AIHA) is a relatively uncommon disorder caused by autoantibodies directed against self red blood cells. It can be idiopathic or secondary, and classified as warm, cold (cold hemagglutinin disease (CAD) and paroxysmal cold hemoglobinuria) or mixed, according to the thermal range of the autoantibody. AIHA may develop gradually, or have a fulminant onset with life-threatening anemia. The treatment of AIHA is still not evidence-based. The first-line therapy for warm AIHA are corticosteroids, which are effective in 70-85% of patients and should be slowly tapered over a time period of 6-12 months. For refractory/relapsed cases, the current sequence of second-line therapy is splenectomy (effective approx. in 2 out of 3 cases but with a presumed cure rate of up to 20%), rituximab (effective in approx. 80-90% of cases), and thereafter any of the immunosuppressive drugs (azathioprine, cyclophosphamide, cyclosporin, mycophenolate mofetil). Additional therapies are intravenous immunoglobulins, danazol, plasma-exchange, and alemtuzumab and high-dose cyclophosphamide as last resort option. As the experience with rituximab evolves, it is likely that this drug will be located at an earlier point in therapy of warm AIHA, before more toxic immunosuppressants, and in place of splenectomy in some cases. In CAD, rituximab is now recommended as first-line treatment.

Systematic review of the presentation of coagulation factor VIII inhibitors in rheumatic diseases: A potential cause of life-threatening hemorrhage

OBJECTIVES

To provide a comprehensive review regarding the clinical presentation of acquired factor VIII (FVIII) inhibitors, also known as "acquired hemophilia," in patients with rheumatic diseases.

METHODS

A systematic MEDLINE search was conducted to identify English-language articles published from 1993 through January 10, 2012, providing details regarding the clinical presentation, laboratory evaluation, and management of a patient(s) with newly or previously diagnosed autoimmune disease coexistent with an acquired FVIII inhibitor.

RESULTS

In total, 49 patients fulfilled the criteria for inclusion in the review; the greatest percentage (24.5%) had systemic lupus erythematosus, followed by rheumatoid arthritis (16%). The majority (78%) presented with spontaneous mucocutaneous or muscular bleeding. Prolonged activated partial thromboplastin time (aPTT) was identified in all of the 45 patients for whom results were provided. Five patients presented with an asymptomatic prolonged aPTT, which was attributed to a lupus anticoagulant in two patients, only one of whom actually had a coexisting lupus anticoagulant. Invasive procedures led to serious bleeding in both of these patients, one of whom died as a result. The majority (59%) of patients experienced complete or partial remission of their inhibitors, most (96%) after systemic eradicative therapy. A total of three (6%) patients died as a direct result of FVIII inhibitors.

CONCLUSIONS

Although acquired FVIII inhibitors are rare in patients with autoimmune diseases, prompt diagnosis is essential to avoid extensive bleeding, which could be life threatening. Treatment requires eradication of the factor inhibitors. Rheumatologists must be able to distinguish acquired FVIII inhibitors from lupus anticoagulants.

Acquired Von Willebrand's Syndrome in Systemic Lupus Erythematosus

Acquired von Willebrand syndrome (AVWS) is an uncommon, underdiagnosed, and heterogeneous disease which is increasingly recognized as a cause of bleeding diatheses. Systemic lupus erythematosus (SLE) is an infrequent cause of AVWS. Herein, we report a case of AVWS diagnosed during the initial presentation of SLE in a previously healthy young man with no family history of bleeding diathesis who presented with worsening epistaxis, gastrointestinal bleeding, and anasarca. He was found to have severe anemia and prolonged activated partial thromboplastin time (aPTT) with severely decreased levels of von Willebrand factor (VWF) measurements in addition to markedly decreased factor VIII levels. Further evaluation revealed nephrotic syndrome and interstitial lung disease due to SLE. He initially received combination therapy with intravenous immunoglobulin (IVIG) and von Willebrand factor/factor VIII concentrates without significant improvement. Treatment with steroids, cyclophosphamide, and rituximab was followed by clinical improvement evidenced by cessation of bleeding. The short follow-up did not allow us to definitely prove the therapeutic effect of immunosuppressive treatment on AVWS in SLE patients. This case adds to the literature supporting the relationship between AVWS and SLE and highlights the importance of combination therapy in the treatment of severe AVWS as well as the role of IVIG, cyclophosphamide, and rituximab in AVWS associated with SLE.

Targeted therapy in antiphospholipid syndrome

PURPOSE OF REVIEW

To review novel therapeutic targets that are currently under investigation to develop safer, targeted therapies for antiphsopholipid antibody (aPL)-mediated clinical manifestations.

RECENT FINDINGS

Novel therapeutic options potentially available include anti-CD20 monoclonal antibodies and new-generation anticoagulants (such as direct thrombin and anti-Xa inhibitors). Research focusing on interfering with aPL-mediated cell activation, targeting complement components and the innovative concept of blocking the pathogenic subpopulation of aPL with tailored peptides are currently being explored.

SUMMARY

Antiphospholipid syndrome is an autoimmune disease characterized by thrombosis and pregnancy morbidity occurring in patients persistently positive for aPL. Current therapeutic options remain confined to long-term anticoagulation with vitamin K antagonists. The future holds much promise with the identification of novel potential targets, many of which are currently under investigation. The challenge will be to design prospective randomized controlled clinical trials to provide the evidence necessary to support integration of these therapies into clinical practice.

Clinical heterogeneity and predictors of outcome in primary autoimmune hemolytic anemia: a GIMEMA study of 308 patients

The clinical outcome, response to treatment, and occurrence of acute complications were retrospectively investigated in 308 primary autoimmune hemolytic anemia (AIHA) cases and correlated with serological characteristics and severity of anemia at onset. Patients had been followed up for a median of 33 months (range 12-372); 60% were warm AIHA, 27% cold hemagglutinin disease, 8% mixed, and 5% atypical (mostly direct antiglobulin test negative). The latter 2 categories more frequently showed a severe onset (hemoglobin [Hb] levels ≤6 g/dL) along with reticulocytopenia. The majority of warm AIHA patients received first-line steroid therapy only, whereas patients with mixed and atypical forms were more frequently treated with 2 or more therapy lines, including splenectomy, immunosuppressants, and rituximab. The cumulative incidence of relapse was increased in more severe cases (hazard ratio 3.08; 95% confidence interval, 1.44-6.57 for Hb ≤6 g/dL; P < .001). Thrombotic events were associated with Hb levels ≤6 g/dL at onset, intravascular hemolysis, and previous splenectomy. Predictors of a fatal outcome were severe infections, particularly in splenectomized cases, acute renal failure, Evans syndrome, and multitreatment (4 or more lines). The identification of severe and potentially fatal AIHA in a largely heterogeneous disease requires particular experienced attention by clinicians.

Acquired hemophilia in the patient suffering from rheumatoid arthritis: case report

Acquired hemophilia is a severe bleeding diathesis caused by autoantibodies against a coagulation factor VIII (FVIII inhibitor). Massive bleeding diathesis, often life threatening are observed in almost 90% of patients. In 50-60% of cases, inhibitor emerges spontaneously. However, there are some conditions like pregnancy, puerperium, autoimmune disorders or cancers that seem to induce acquired hemophilia. We report a case of a 49-year-old woman suffering from rheumatoid arthritis (RA) for several years, who was diagnosed with acquired hemophilia in September 2011. The patient had been treated by steroids and leflunomide during the last few months. At the time of diagnosis, diffuse bruising of the forearms and the trunk was observed. The patient was treated with recombinant activated factor VII, and the first-line immunosuppressive therapy was introduced (cyclophosphamide and prednisone). We observed the elimination of symptoms and the disappearance of diathesis. Significant reduction of the titer of inhibitor was achieved, but only partial remission was obtained. It lasted until the beginning of December 2011, when the titer of the inhibitor increased again and massive bleeding to the left lower limb occurred. It was necessary to administer recombinant factor VIIa together with the second-line immunosuppressive therapy based on the Budapest protocol. The rapid reduction of the diathesis and improvement of the patient's general condition was achieved as previously. However, still there was no complete remission. After 2 weeks of treatment, the titer of inhibitor diminished, and factor VIII activity increased slightly. Because of RA, the patient was treated with methylprednisolone in maintenance doses during the next few weeks. Unfortunately, after over a month, the increase of inhibitor titer and the decrease of FVIII level were observed again. Some bruises appeared. It was necessary to increase doses of corticosteroids to therapeutic levels and add cyclophosphamide in low doses to prevent the appearance of more hemorrhagic diathesis. Partial remission was achieved a second time at the end of April 2012. The patient was given methylprednisolone with chloroquine as a maintenance treatment and the control of RA. The titer of the inhibitor increased again in June 2012, but there were no signs of diathesis. In August 2012, some bruises were detected, and we decided to add cyclophosphamide again instead of escalating the doses of methylprednisolone to prevent the occurrence of side-effects of corticosteroids. Cyclophosphamide was given with intervals only depending on activated partial thromboplastin time. No further diathesis was observed in spite of the lack of remission. We were forced to withdrawn cyclophosphamide completely in October 2012 because of signs of hematuria. Fortunately, right nephrolithiasis and urinary tract infection were the cause of that condition. These symptoms vanished after standard supportive treatment. Maintenance doses of corticosteroids and chloroquine were continued as the main treatment. The patient's condition was good, but the titer of inhibitor increased over the value that had been detected at the time of diagnosis, and some bruises appeared again at the end of January 2013. The decision to use rituximab as the next-line therapy was made. This anti-CD20 monoclonal antibody is primarily used in the management of lymphomas. However, it has been successfully applied in the management of various autoimmune conditions. The usual treatment regime involves four separate intravenous infusions of 375 mg/m each, administered at weekly intervals. At the time of admission to the hospital in the second half of February 2013, the titer of inhibitor was dangerously high, almost three times more than the initial level. Fortunately, only a few bruises were observed, and no bypassing agents were needed. The patient was given the whole-planned therapy. Concomitant continuation of maintenance doses of corticosteroids was necessary to enforce the effect of eradication of inhibitor because of high levels of its titer during rituximab administration. It prevented the patient from massive diathesis that might occur. The laboratory tests were improving during the next subsequent weeks after the last dose of rituximab. Over a month later, a significant decrease of the titer of inhibitor and an increase of factor VIII activity was observed. Probably, the laboratory tests will be improving during the next few weeks. The patient is in outpatient care now. She is treated with maintenance doses of corticosteroids and chloroquine as the main treatment of RA. We will try to withdraw corticosteroids unless it is not feasible to achieve complete remission. We will have to introduce another kind of immunosuppressive agent in case of recurrence.

Anti-CD20 monoclonal antibodies and associated viral hepatitis in hematological diseases

Over the past decade, the administration of anti-CD20 monoclonal antibodies such as rituximab has demonstrated various degrees of effectiveness and has improved patients’ outcomes during the treatment of autoimmune hematological disorders and hematological malignancies. However, the depletion of B-cells, the distribution of T-cell populations, and the reconstruction of host immunity resulting from the use of anti-CD20 monoclonal antibodies potentially lead to severe viral infections, such as hepatitis B virus (HBV), hepatitis C virus (HCV), parvovirus B19, and herpes viruses, in patients who are undergoing immune therapy or immunochemotherapy. Of these infections, HBV- and HCV-related hepatitis are a great concern in endemic areas because of the high morbidity and mortality rates in untreated patients. As a result, prophylaxis against HBV infection is becoming a standard of care in these areas. Parvovirus B19, a widespread pathogen that causes red blood cell aplasia in immunocompromised hosts, also causes hepatitis in healthy individuals. Recently, its association with hepatitis was recognized in a patient treated with rituximab. In addition, adenovirus, varicella-zoster virus, hepatitis E virus, and rituximab itself have been linked to the occurrence of hepatitis during or after rituximab treatments. The epidemiologies and pathogeneses of these etiologies remain unknown. Because of the increasing use of anti-CD20 monoclonal antibodies for the treatment of hematological malignancies or autoimmune hematological disorders, it is imperative that physicians understand and balance the risks of hepatotropic virus-associated hepatitis against the benefits of using anti-CD20 monoclonal antibodies.

Inhibitor eradication with rituximab in haemophilia: where do we stand?

Rituximab is a humanized chimeric anti-CD20 monoclonal antibody initially developed for the treatment of some haematological malignancies. Thanks to its ability to rapidly and specifically deplete B cells, it has also been used in a variety of autoimmune disorders, haematological or not. In this context, during the last decade several small case series have documented successful inhibitor eradication with rituximab, alone or in combination with other immunosuppressive agents, in patients with acquired haemophilia A refractory to standard therapy. In addition, a number of investigators have recently used this agent in patients with congenital haemophilia A or B and alloantibodies refractory to first-line treatment. This article critically reviews the current knowledge on the use of rituximab in acquired haemophilia or congenital haemophilia complicated by alloantibodies, also providing treatment algorithms for the management of these conditions.

B-Cell Targeted Therapies in Autoimmune Cytopenias and Thrombosis

Ever since the advent of Rituximab and subsequently the emergence of other compounds targeting B cells, a cornucopia of medical applications have been found for this family of compounds. After their establishment as standard of care in many conditions such as rituximab in lymphoma and rheumatoid arthritis, they have been progressively found to aid in the treatment of many other conditions. This area constituted a fertile area of research in the past 12 years. Physicians have investigated the B-cell depleting agents use in cases of autoimmune hematologic cytopenias such as immune thrombocytopenia, Evans syndrome, cold and warm autoimmune hemolytic anemia, and other thrombophilic disorders such as the antiphospholipid syndrome and thrombocytopenic purpura. This chapter presents a historical perspective reviewing the various studies that have been published in this field. In addition, it offers a current assessment of the evidence regarding the use of B-cell depleting agents in the aforementioned conditions.

Rituximab effectiveness in a patient with juvenile systemic lupus erythematosus complicated with acquired Von Willebrand syndrome

The acquired von Willebrand Syndrome (AvWS) is a bleeding disorder with laboratory findings similar to those of the congenital form. Its presentation is more common in adults than in children and is mainly associated with lymphoproliferative and myeloproliferative diseases and rarely with autoimmune diseases including systemic lupus erythematosus (SLE). Here, we report the case of a girl with SLE and AvWS with mucosal bleeding and low plasma levels of von Willebrand factor and factor VIII (FVIII) with failure to respond to treatment with first- and second-line therapies. The patient finally responded to rituximab. To our knowledge this is the first reported case of SLE associated with AvWS, that responded to rituximab.

Anti-CD20 monoclonal antibodies: beyond B-cells

Anti-CD20 monoclonal antibodies (MoAbs), employed in treating CD20⁺ lymphomas and autoimmune diseases, appear to have broader functions than just eradicating malignant B-cells and decreasing autoantibody production. Rituximab-induced T-cell inactivation, reported both in-vitro and in-vivo, may contribute to the increased risk of T-cell-dependent infections, observed in patients receiving this therapy. T-cell polarization into a suppressive phenotype, often observed in patients receiving rituximab for autoimmune disorders, was reported to be associated with prolonged remissions. Elimination of B-cells serving as antigen-presenting cells, thereby causing impaired T-cell activation, could play a significant role in induction of these changes. Direct binding of rituximab to a CD20dim T-cell population, inducing its depletion, may contribute to the decreased T-cell activation following rituximab therapy. Further investigation of the complex network through which rituximab and new anti-CD20 MoAbs act, would advance the employment of these agents in different clinical settings.

Rituximab for thrombotic thrombocytopenic purpura: benefit of early administration during acute episodes and use of prophylaxis to prevent relapse

BACKGROUND

Rituximab has been documented in the treatment of acute (≤ 3 days from admission), relapsed/refractory thrombotic thrombocytopenic purpura (TTP) and given as prophylaxis in selected cases to prevent acute relapse. The precise timing of rituximab in acute TTP has not been determined.

OBJECTIVE

To perform a retrospective analysis of rituximab use in a large TTP referral center over an 8-year period.

PATIENTS/METHODS

We assessed response to treatment and outcome for all patients treated with rituximab, including 91 patients presenting with 104 episodes of acute TTP and 15 patients given rituximab as prophylaxis to prevent relapse. In the acute TTP group we assessed the benefit of giving early (≤ 3 days from admission) vs. later (> 3 days) rituximab.

RESULTS

In acute de novo TTP, previously untreated with rituximab, rituximab was given ≤ 3 days from admission to 54 patients and > 3 days from admission to 32 patients. Earlier administration (≤ 3 days) was associated with faster attainment of remission (12 vs. 20 days, P < 0.001), fewer plasma exchanges (16 vs. 24, P = 0.03) and shorter hospital stay (16 vs. 23 days, P = 0.01). Eighty-two patients (95%) achieved complete remission within 14 days (4-52 days); four patients died acutely. Eleven out of 82 (13.4%) relapsed at a median of 24 months (4-49 months). Rituximab prophylaxis was associated with normalization of ADAMTS13 levels within 3 months in all but one case, with only one acute relapse at follow-up.

CONCLUSIONS

Although limited by being retrospective and non-randomized, this study demonstrates the potential benefit of early administration of rituximab in acute TTP, and prophylactic use to prevent acute relapse.

Emerging roles for protein S-palmitoylation in immunity from chemical proteomics

The activation of innate and adaptive immune signaling pathways and effector functions often occur at cellular membranes and are regulated by complex mechanisms. Here we review the growing number of proteins which are known to be regulated by S-palmitoylation in immune cells emerging from recent advances in chemical proteomics. These chemical proteomic studies have highlighted the roles of this dynamic lipid modification in regulating the specificity and strength of immune responses in different lymphocyte populations.

Rituximab for the treatment of patients with autoimmune hepatitis who are refractory or intolerant to standard therapy

BACKGROUND

Although most patients with autoimmune hepatitis (AIH) respond to treatment with prednisone and⁄or azathioprine, some patients are intolerant or refractory to standard therapy. Rituximab is an anti-CD20 monoclonal antibody that depletes B cells and has demonstrated efficacy in other autoimmune conditions.

AIMS

To evaluate the safety and efficacy of rituximab in patients with refractory AIH in an open-label, single-centre pilot study.

METHODS

Six patients with definite, biopsy-proven AIH who failed prednisone and azathioprine treatment received two infusions of rituximab 1000 mg two weeks apart and were followed for 72 weeks.

RESULTS

Rituximab was well tolerated with no serious adverse events. By week 24, mean (± SD) aspartate aminotransferase (AST) levels had significantly improved (90.0±23.3 U⁄L versus 31.3±4.2 U⁄L; P=0.03) and mean immunoglobulin G levels had fallen (16.4±2.0 g⁄L versus 11.5±1.1 g⁄L; P=0.056). The prednisone dose was weaned in three of four subjects, with one subject flaring after steroid withdrawal. Inflammation grade improved in all four subjects who underwent repeat liver biopsy at week 48. Regulatory T cell levels examined by FoxP3 immunohistochemistry paralleled inflammatory activity and did not increase on follow-up biopsies. There was no significant change in serum chemokine or cytokine levels from baseline to week 24 (n=5), although interferon-gamma-induced protein 10 levels improved in three of five subjects.

CONCLUSIONS

Rituximab was safe, well tolerated and resulted in biochemical improvement in subjects with refractory AIH. These results support further investigation of rituximab as a treatment for AIH.

Hepatitis C virus infection and mixed cryoglobulinemia

Hepatitis C virus (HCV) chronic infection is recognized as the major cause of mixed cryoglobulinemia (MC). Its persistence represents a continuous stimulus for host immune system with production of circulating immune complexes (ICs), one-third of them with cryoprecipitate property. Several factors contribute to the biological activities of ICs, many of which are not completely known. Among them, complement factors play a crucial role in the cold-insoluble ICs-mediated vasculitis, involving primarily small blood vessels in different tissues including skin, kidney, peripheral, and central nervous system. Liver represents the major target of HCV infection with inflammatory infiltrates, resembling secondary lymphoid follicles. Cytokine like CXCL13 contribute to B-cell homing in intraportal lymphoid aggregates, in which B-cell clonal selection may arise. B-cell clonal expansion starts as an antigen-driven event and expands towards indolent and malignant B-cell proliferation. Occurrence of intrahepatic B-cell clonalities correlates with extrahepatic clinical manifestations of HCV infection. In this context, cryoglobulinemic patients should be considered a peculiar HCV-infected population that needs a clinical multidisciplinary approach and more articulated therapeutic measures.

Proteomic analysis of S-acylated proteins in human B cells reveals palmitoylation of the immune regulators CD20 and CD23

S-palmitoylation is a reversible post-translational modification important for controlling the membrane targeting and function of numerous membrane proteins with diverse roles in signalling, scaffolding, and trafficking. We sought to identify novel palmitoylated proteins in B lymphocytes using acyl-biotin exchange chemistry, coupled with differential analysis by liquid-chromatography tandem mass spectrometry. In total, we identified 57 novel palmitoylated protein candidates from human EBV-transformed lymphoid cells. Two of them, namely CD20 and CD23 (low affinity immunoglobulin epsilon Fc receptor), are immune regulators that are effective/potential therapeutic targets for haematological malignancies, autoimmune diseases and allergic disorders. Palmitoylation of CD20 and CD23 was confirmed by heterologous expression of alanine mutants coupled with bioorthogonal metabolic labeling. This study demonstrates a new subset of palmitoylated proteins in B cells, illustrating the ubiquitous role of protein palmitoylation in immune regulation.

The use of monoclonal antibodies in immune-mediated hematologic disorders

In this article, the evidence on the clinical use of monoclonal antibodies in the treatment of immune-mediated hematologic disorders is described. Insights into pathogenic mechanisms have revealed a major role of both B and T cells. Controlled trials have shown conflicting results, necessitating further research regarding pathogenesis, mechanism of action, and resistance. Although the use of more potent and specific monoclonal antibody therapy, mainly targeting costimulation signals, may improve response rates and long-term outcome, its use should be carefully balanced against potential side effects.

Low-dose rituximab in adult patients with idiopathic autoimmune hemolytic anemia: clinical efficacy and biologic studies

This prospective study investigated the efficacy, safety, and response duration of low-dose rituximab (100 mg fixed dose for 4 weekly infusions) together with a short course of steroids as first- or second-line therapy in 23 patients with primary autoimmune hemolytic anemia (AIHA). The overall response was 82.6% at month +2, and subsequently stabilized to ∼ 90% at months +6 and +12; the response was better in warm autoimmune hemolytic anemia (WAIHA; overall response, 100% at all time points) than in cold hemagglutinin disease (CHD; average, 60%); the relapse-free survival was 100% for WAIHA at +6 and +12 months versus 89% and 59% in CHD, respectively, and the estimated relapse-free survival at 2 years was 81% and 40% for the warm and cold forms, respectively. The risk of relapse was higher in CHD and in patients with a longer interval between diagnosis and enrollment. Steroid administration was reduced both as cumulative dose (∼ 50%) and duration compared with the patient's past history. Treatment was well tolerated and no adverse events or infections were recorded; retreatment was also effective. The clinical response was correlated with amelioration biologic markers such as cytokine production (IFN-γ, IL-12, TNF-α, and IL-17), suggesting that low-dose rituximab exerts an immunomodulating activity. This study is registered at www.clinicaltrials.gov as NCT01345708.

B-cell depleting agents for ANCA vasculitides: a new therapeutic approach

Vasculitides associated with anti-neutrophil cytoplasmic antibody (ANCA) serum positivity affecting small and medium-sized vessels are defined as ANCA-associated vasculitis (AAV). Glomerulonephritis in AAV is characterized by focal necrosis, crescent formation, and few or no immunoglobulin deposits. In vitro and animal evidence suggests that ANCA play a pathogenic role in AAV. Specific gene expression signatures are reported to predict long-term prognosis in AAV, suggesting the possibility of individualizing therapy and identifying new therapeutic targets. Although immunosuppressants and glucocorticoids are the cornerstone of AAV therapy, results from two recent randomized controlled trials have shown the non-inferiority of rituximab, compared with cyclophosphamide, for the induction of remission in patients with severe AAV. In fact, in April 2011, the US Food and Drug Administration (FDA) approved rituximab, combined with glucocorticoids, as a front-line therapy for adult patients with granulomatosis with polyangiitis (GPA; Wegener's granulomatosis) or microscopic polyangiitis. This new indication for rituximab provided the first ever FDA-approved therapy for these two diseases and the first alternative to cyclophosphamide for the treatment of severe disease in almost 40years. However, issues regarding the use of maintenance therapy after rituximab, the concurrent use of cyclophosphamide and the toxicity of rituximab remain unanswered and should be clarified in ongoing and future randomized controlled trials.