Recommendations for the management of secondary hypogammaglobulinaemia due to B cell targeted therapies in autoimmune rheumatic diseases

The evolving role of B cells in malignancies

B cells play diverse roles in different pathological circumstances, such as neoplastic diseases, autoimmune disorders, and neurological maladies. B cells, which are essential elements of the adaptive immune system, demonstrate exceptional functional variety, including the generation of antibodies, the presentation of antigens, and the secretion of cytokines. Within the field of oncology, B cells display a multifaceted nature in the tumor microenvironment, simultaneously manifesting both tumor-promoting and tumor-suppressing characteristics. Studies have found that the existence of tertiary lymphoid structures, which consist of B cells, is linked to better survival rates in different types of cancers. This article examines the involvement of B cells in different types of malignancies, emphasizing their importance in the development of the diseases and their potential as biomarkers. Additionally, the review also examines the crucial role of B cells in autoimmune illnesses and their potential as targets for therapy. The article also analyses the role of B cells in immunization and exploring their potential uses in cancer immunotherapy. This analysis highlights the intricate and occasionally contradictory roles of B cells, underlining the necessity for additional research to clarify their varied actions in various illness scenarios.

Impact of High-Efficacy Therapies for Multiple Sclerosis on B Cells

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative autoimmune disorder of the central nervous system characterized by demyelination and neurodegeneration. Traditionally considered a T-cell-mediated disease, the crucial role of B lymphocytes in its pathogenesis, through different mechanisms contributing to inflammation and autoreactivity, is increasingly recognized. The risk of long-term disability in MS patients can be reduced by an early treatment initiation, in particular with high-efficacy therapies. The aim of this review is to provide an overview of the mechanisms of action of high-efficacy therapies for MS, with a focus on their impact on B cells and how this contributes to the drugs' efficacy and safety profiles. Anti-CD20 monoclonal antibodies, Alemtuzumab, Cladribine and sequestering therapies encompassing Natalizumab and S1P receptors modulators will be discussed and emerging therapies, including Bruton's Tyrosine Kinase inhibitors, will be presented.

Hyperacute reactivation of cytomegalovirus-induced gastroduodenitis during remission induction in a young male patient with granulomatosis with polyangiitis: a case report and review of literature

BACKGROUND

Cytomegalovirus is a pathogen known to aggravate the inflammatory response in autoimmune diseases via molecular mimicry. Although it is recognized that cytomegalovirus activation can happen during extended but variable periods of immunosuppression (14-90 days), it is rarely reported in conjunction with an acute flare-up of an autoimmune disease. Currently, there is no consensus on cytomegalovirus prophylaxis for patients initiating remission induction.

CASE PRESENTATION

Here, we present the case of a 31-year-old male patient of South Indian ethnicity, presenting with a 2-month history of fever, conductive hearing loss, and ear discharge. This was associated with symmetrical inflammatory polyarthritis for 1 month, unilateral painful conjunctivitis, and skin erythema for 5 days. Blood analyses showed elevated inflammatory markers; strongly positive anti-proteinase 3 and cytoplasmic antineutrophil cytoplasmic antibody levels; normal procalcitonin and complement levels; and negative anti-myeloperoxidase and perinuclear antineutrophil cytoplasmic antibody levels. A nasal endoscopy revealed a midline granuloma with vasculitis features on biopsy. Imaging revealed pulmonary nodules and otomastoiditis. Now diagnosed with granulomatosis with polyangiitis, the patient developed signs of gastroduodenitis within a day of initiation of immunosuppression with high-dose "pulse" intravenous methylprednisolone. We evaluated him for mesenteric ischemia/gastrointestinal vasculitis. However, the duodenal biopsies from the bleeding ulcers revealed a probable cytomegalovirus infection, confirmed with high serum viral loads. We treated him with a ganciclovir regimen and transitioned him to steroid-sparing immunosuppressant therapy with mycophenolate mofetil, which was selected over cyclophosphamide for its noninferior effectiveness and better safety profile in non-life-threatening granulomatosis with polyangiitis disease. The patient recovered uneventfully and is currently in remission.

CONCLUSION

Cytomegalovirus reactivation is possible during short-term steroid pulse therapy. Further research is needed to evaluate whether routine cytomegalovirus screening is warranted before starting immunosuppressive treatment with high-dose steroids in autoimmune conditions.

Top ten tips in managing ANCA vasculitis

Diagnosing and managing antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) remain a challenge for many clinicians, due to the complexity of the disease manifestations and its treatment. There has been a paradigm shift in ANCA vasculitis management, where treatment incorporates both emergency life- and organ-saving procedures and longer-term care to manage relapse and co-morbidity risk and the complications of organ damage. Here, we highlight 10 key tips for the management of ANCA-associated vasculitis based on current evidence and clinical experience. First, we advise making the diagnosis as early as possible, emphasizing the importance of using high-quality ANCA assays. Second, we recommend the use of glucocorticoids in combination with rituximab and/or cyclophosphamide as induction therapy. Third, plasma exchange should be considered in patients with severe renal impairment and diffuse alveolar haemorrhage. We advise the use of rapidly reducing glucocorticoid regimens and advocate consideration of avacopan early in the disease course. We recommend the use of rituximab as maintenance therapy and routine monitoring of kidney function, proteinuria, ANCA and immunoglobulin levels at baseline and during follow-up. The use of prophylactic antibiotics in susceptible patients and timely vaccination schedules is discussed. Rituximab is the preferred immune suppressive for treatment of relapse. Finally, we recommend switching treatment modalities in patients whose vasculitis is refractory to induction therapy and to consider plasma exchange in selected patients. These key tips aim to provide the necessary guidance to improve patient outcomes and reduce adverse events.

Recommendations for the diagnosis and treatment of anti-neutrophil cytoplasmic autoantibody associated vasculitis

Anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis is characterised by small vessel necrotising inflammatory vasculitis. Prior to immunosupressant therapy availability it usually led to a fatal outcome. Current treatment has changed ANCA-associated vasculitis into a condition with a significant response rate, although with a not negligible relapse occurrence and cumulative organ lesions, mostly due to drug-related toxicities. The use of glucocorticoids, cyclophosphamide and other immunosupressants (such as azathioprine, mychophenolate and methotrexate) was optimised in a series of clinical trials that established the treatment of reference. In recent years, a better knowledge of B lymphocyte function and the role of complement inhibition has transformed the course of this disease while minimising treatment-related adverse effects. This multidisciplinary document of recommendations is based on the consensus of three scientific societies (Internal Medicine, Nephrology and Rheumatology) and on the best available evidence on diagnosis, treatment and follow-up of patients with ANCA-associated vasculitis, including some special situations. The aim of this document is to provide updated information and well-grounded clinical recommendations to practising physicians as to how to improve the diagnosis and treatment outcome of our patients.

Disseminated septic arthritis caused by Ureaplasma urealyticum in an immunocompromised patient with hypogammaglobulinemia after rituximab therapy

PURPOSE

Ureaplasma urealyticum is a rare pathogen associated with septic arthritis that predominantly affects patients with hypogammaglobulinemia. Bacterial identification of fastidious organisms is challenging because they are undetectable by routine culture testing. To the best of our knowledge, this is the first report of septic arthritis induced by U. urealyticum infection in Japan.

CASE DESCRIPTION

We describe the case of a 23-year-old Japanese female with secondary hypogammaglobulinemia (serum immunoglobulin level < 500 mg/dL), identified 8 years after treatment with rituximab. The patient presented with persistent fever and polyarthritis that were unresponsive to ceftriaxone and prednisolone. Contrast-enhanced computed tomography and gallium-67 scintigraphy revealed effusion and inflammation in the left sternoclavicular, hip, wrist, knee, and ankle joints. Although Gram staining and bacterial culture of the drainage fluid from the left hip joint were negative, the condition exhibited characteristics of purulent bacterial infection. The patient underwent empirical treatment with doxycycline, and her symptoms promptly resolved. Subsequent 16S ribosomal RNA (rRNA) gene sequencing of the joint fluid confirmed the presence of U. urealyticum, leading to the diagnosis of septic arthritis. Combination therapy with doxycycline and azithromycin yielded a favorable recovery from the inflammatory status and severe arthritic pain.

CONCLUSION

This case highlights U. urealyticum as a potential causative agent of disseminated septic arthritis, particularly in patients with hypogammaglobulinaemia. The 16S rRNA gene analysis proved beneficial for identifying pathogens in culture-negative specimens, such as synovial fluid, in suspected bacterial infections.

Current perspective on infections and mitigation strategies in primary systemic vasculitis

PURPOSE OF REVIEW

The purpose of this review is to summarize and evaluate most recent evidence on the epidemiology of infections and associated risk factors in patients with primary systemic vasculitides (PSV), as well as discuss mitigation strategies including the risk of antibiotic prophylaxis.

RECENT FINDINGS

Infections remain one of the leading causes of mortality in patients with PSV, with rates of severe infection ranging from 16 to 40% in different cohorts. Older age, frailty, renal and pulmonary involvement, and higher burden of comorbidities have been recognized as important patient-associated risk factors. Treatments including higher cumulative doses of glucocorticoids are associated with an increased risk of infections, and recent studies show the potential benefit of interventions such as reduced-dose glucocorticoid regimens. Existing mitigation strategies include screening, vaccination, and infection prophylaxis. The latter remains particularly important for Pneumocystis jirovecii pneumonia; however, the benefit-risk ratio seems to be less clear outside of induction phase (i.e., high dose of glucocorticoids) and optimal treatment duration remains less clear. Patients with PSV are at increased risk of infections, due to disease itself, comorbidities, and treatment side effects. Awareness of the timing and types of infection, as well as mitigation strategies are imperative to ensure treatment success and survival for patients.

Bronchiectasis, lymphadenopathies related to BAFF overexpression and lymphoplasmacytic cystitis as adverse events associated with prolonged use of rituximab in systemic autoimmune rheumatic diseases

BACKGROUND

The long-term use of rituximab (RTX) has been gaining ground in the treatment of systemic autoimmune diseases. The adverse events (AEs) associated with its use different to infections are being reported.

METHODS

A cohort of patients with SAIDs treated at a high-complexity center in Cali (southwestern Colombia) with follow-up from January 2008 to December 2022 were examined to search for potential AEs associated with prolonged use of RTX.

RESULTS

From 178 patients with long-term use of RTX 3 (1.68%) had lymphadenopathies with lymphoid follicular hyperplasia related to BAFF overexpression, 4 (2.24%) with bronchiectasis, and 4 (2.24%) with lymphoplasmacytic cystitis.

CONCLUSION

Bronchiectasis, lymphoid follicular hyperplasia related to BAFF overexpression, and lymphoplasmacytic cystitis may be life-threatening long-term AEs in patients with prolonged use of RTX.

[Influence of underlying disease and immunosuppression on the immunocompetence in inflammatory rheumatic diseases]

Patients with inflammatory rheumatic diseases have a higher risk of infections in comparison to the general population. For this patient group, in addition to cardiovascular diseases, infections play an important role with respect to morbidity and mortality. Even if it is difficult to make concrete statements with respect to individual diseases, it can be assumed that there is a lower risk of infections in inflammatory joint diseases in comparison to connective tissue diseases and vasculitides. The increased risk of infections is determined by multiple factors, whereby the underlying factors are classified into three main categories: patient-related factors (age, comorbidities, lifestyle), disease-related factors (immunological dysfunction as part of the disease pathophysiology) and drug-related factors (type and dosage of the immunosuppression and/or immunomodulation). An improved understanding of the complexity of these associations enables the optimization of treatment and disease control taking the individual risk factors into account, with the aim of a significant reduction in the risk of infections.

Diagnosis and management of ANCA-associated vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis consists of two main diseases, granulomatosis with polyangiitis and microscopic polyangiitis, and remains among the most devastating and potentially lethal forms of autoimmune inflammatory disease. Granulomatosis with polyangiitis and microscopic polyangiitis are characterised by a necrotising vasculitis that can involve almost any organ, and have generally been studied together. The diseases commonly affect the kidneys, lungs, upper respiratory tract, skin, eyes, and peripheral nerves. Granulomatous inflammation and multinucleated giant cells are key pathological hallmarks of granulomatosis with polyangiitis, but are absent in microscopic polyangiitis. Many immune system events are essential to disease aetiopathogenesis, such as activation of the alternative complement pathway, neutrophil activation via complement receptors, and the influx of inflammatory cells, including monocytes and macrophages. These cells perpetuate inflammation and lead to organ damage. During the 21st century, the management of ANCA-associated vasculitis has moved away from reliance on cytotoxic medications and towards targeted biological medications for both the induction and maintenance of disease remission. Earlier diagnosis, partly the result of more reliable ANCA testing, has led to improved patient outcomes and better survival. Reductions in acute disease-related mortality have now shifted focus to long-term morbidities related to ANCA-associated vasculitis and their treatments, such as chronic kidney disease and cardiovascular disease. Therapeutic approaches in both clinical trials and clinical practice still remain too reliant on glucocorticoids, and continued efforts to reduce toxicity from glucocorticoids remain a priority in the development of new treatment strategies.

EULAR recommendations for the management of ANCA-associated vasculitis: 2022 update

BACKGROUND

Since the publication of the EULAR recommendations for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in 2016, several randomised clinical trials have been published that have the potential to change clinical care and support the need for an update.

METHODS

Using EULAR standardised operating procedures, the EULAR task force undertook a systematic literature review and sought opinion from 20 experts from 16 countries. We modified existing recommendations and created new recommendations.

RESULTS

Four overarching principles and 17 recommendations were formulated. We recommend biopsies and ANCA testing to assist in establishing a diagnosis of AAV. For remission induction in life-threatening or organ-threatening AAV, we recommend a combination of high-dose glucocorticoids (GCs) in combination with either rituximab or cyclophosphamide. We recommend tapering of the GC dose to a target of 5 mg prednisolone equivalent/day within 4-5 months. Avacopan may be considered as part of a strategy to reduce exposure to GC in granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA). Plasma exchange may be considered in patients with rapidly progressive glomerulonephritis. For remission maintenance of GPA/MPA, we recommend rituximab. In patients with relapsing or refractory eosinophilic GPA, we recommend the use of mepolizumab. Azathioprine and methotrexate are alternatives to biologics for remission maintenance in AAV.

CONCLUSIONS

In the light of recent advancements, these recommendations provide updated guidance on AAV management. As substantial data gaps still exist, informed decision-making between physicians and patients remains of key relevance.

Daratumumab for autoimmune diseases: a systematic review

OBJECTIVE

Refractory autoimmune diseases remain a significant challenge in clinical practice and new therapeutic options are needed. This systematic review evaluates the existing reported data on the CD38-targeting antibody daratumumab as a new therapeutic approach in autoantibody-mediated autoimmune diseases.

METHODS

A protocolised systematic literature review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed. Two databases (Medline and Embase) were searched for suitable studies. Usage of daratumumab in non-oncological or non-transplantation associated diseases with autoimmune pathophysiology was analysed including patient characteristics, therapeutic regimen, adverse events and patient outcome.

RESULTS

38 publications reporting the clinical course of 83 patients met the inclusion criteria. Daratumumab usage was reported in therapy-refractory cases (median of 5 different previous therapies) in 24 different autoimmune diseases. The median number of applications of daratumumab was 4, mainly via intravenous applications (87%). Concomitant treatment included glucocorticoids in 64% of patients, intravenous immunoglobulins (33%) and rituximab (17%). Remission or improvement of disease was reported in 81% of patients. Autoantibody depletion or reduction was stated in 52% of patients. Death occurred in three patients (3%). Adverse events were reported in 45% of patients including application-associated reaction (20%), infection (19%) and hypogammaglobulinaemia (33%).

CONCLUSION

Targeting CD38 via daratumumab is a new promising therapeutic option in therapy refractory autoimmune diseases. Efficacy as well as optimal therapeutic regimen and management or prevention of adverse events require further investigation. Therefore, systematic clinical trials of this therapeutic approach are needed.

Long-term outcomes with rituximab as add-on therapy in severe childhood-onset lupus nephritis

BACKGROUND

Long-term data pertaining to rituximab as add-on therapy in childhood-onset lupus nephritis (cLN) is scarce.

METHODS

A retrospective cohort study was conducted on all patients with proliferative cLN, diagnosed ≤ 18 years and between 2005 and 2021, who received rituximab for LN episodes that were life/organ threatening and/or treatment resistant to standard immunosuppression.

RESULTS

Fourteen patients with cLN (female, n = 10) were included, with median follow-up period of 6.9 years. LN episodes (class III, n = 1; class IV, n = 11; class IV + V, n = 2) requiring rituximab occurred at 15.6 years (IQR 12.8-17.3), urine protein:creatinine ratio was 8.2 mg/mg (IQR 3.4-10.1) and eGFR was 28 mL/min/1.73 m2 (IQR 24-69) prior to rituximab treatment. Ten and four patients received rituximab at 1500 mg/m2 and 750 mg/m2, which were given at 46.5 days (IQR 19-69) after commencement of standard therapies. Treatment with rituximab resulted in improvements in proteinuria (ps < 0.001), eGFR (ps < 0.01) and serological parameters, including haemoglobin levels, complement 3 levels and anti-dsDNA antibodies, compared with baseline. Rates of complete/partial remission at 6-, 12- and 24-month post-rituximab were 28.6/42.8%, 64.2/21.4% and 69.2/15.3%. All three patients who required acute kidney replacement therapy became dialysis-free after rituximab. Relapse rate following rituximab was 0.11 episodes/patient-year. There was no lethal complication or severe infusion reaction. Hypogammaglobulinaemia was the most frequent complication (45%) but was mostly asymptomatic. Neutropenia and infections were observed in 20% and 25% of treatments. Upon last follow-up, three (21%) and two (14%) patients developed chronic kidney disease (stage 2, n = 2; stage 4; n = 1) and kidney failure, respectively.

CONCLUSION

Add-on rituximab is an effective and safe rescue therapy for cLN patients with life-/organ-threatening manifestations or treatment-resistance. A higher resolution version of the Graphical abstract is available as Supplementary information.

Preventing infections in immunocompromised patients with kidney diseases: vaccines and antimicrobial prophylaxis

The coronavirus disease 2019 (COVID-19) pandemic revealed that our understanding of infectious complications and strategies to mitigate severe infections in patients with glomerular diseases is limited. Beyond COVID-19, there are several infections that specifically impact care of patients receiving immunosuppressive measures. This review will provide an overview of six different infectious complications frequently encountered in patients with glomerular diseases, and will focus on recent achievements in terms of vaccine developments and understanding of the use of specific antimicrobial prophylaxis. These include influenza virus, Streptococcus pneumoniae, reactivation of a chronic or past infection with hepatitis B virus in cases receiving B-cell depletion, reactivation of cytomegalovirus, and cases of Pneumocystis jirovecii pneumonia in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis. Varicella zoster virus infections are particularly frequent in patients with systemic lupus erythematosus and an inactivated vaccine is available to use as an alternative to the attenuated vaccine in patients receiving immunosuppressants. As with COVID-19 vaccines, vaccine responses are generally impaired in older patients, and after recent administration of B-cell depleting agents, and high doses of mycophenolate mofetil and other immunosuppressants. Strategies to curb infectious complications are manifold and will be outlined in this review.

Secondary hypogammaglobulinemia in patients with multiple sclerosis on anti-CD20 therapy: Pathogenesis, risk of infection, and disease management

Hypogammaglobulinemia is characterized by reduced serum immunoglobulin levels. Secondary hypogammaglobulinemia is of considerable interest to the practicing physician because it is a potential complication of some medications and may predispose patients to serious infections. Patients with multiple sclerosis (MS) treated with B-cell-depleting anti-CD20 therapies are particularly at risk of developing hypogammaglobulinemia. Among these patients, hypogammaglobulinemia has been associated with an increased risk of infections. The mechanism by which hypogammaglobulinemia arises with anti-CD20 therapies (ocrelizumab, ofatumumab, ublituximab, rituximab) remains unclear and does not appear to be simply due to the reduction in circulating B-cell levels. Further, despite the association between anti-CD20 therapies, hypogammaglobulinemia, and infections, there is currently no generally accepted monitoring and treatment approach among clinicians treating patients with MS. Here, we review the literature and discuss possible mechanisms of secondary hypogammaglobulinemia in patients with MS, hypogammaglobulinemia results in MS anti-CD20 therapy clinical trials, the risk of infection for patients with hypogammaglobulinemia, and possible strategies for disease management. We also include a suggested best-practice approach to specifically address secondary hypogammaglobulinemia in patients with MS treated with anti-CD20 therapies.

Rituximab-associated hypogammaglobulinemia in children with idiopathic nephrotic syndrome: results of an ESPN survey

BACKGROUND

There is paucity of information on rituximab-associated hypogammaglobulinemia (HGG) and its potential infectious consequences in children treated for idiopathic nephrotic syndrome (INS).

METHODS

A survey was distributed by the European Society Pediatric Nephrology to its members. It addressed the screening and management practices of pediatric nephrology units for recognizing and treating RTX-associated HGG and its morbidity and mortality. Eighty-four centers which had treated an overall 1328 INS children with RTX responded.

RESULTS

The majority of centers administered several courses of RTX and continued concomitant immunosuppressive therapy. Sixty-five percent of centers routinely screened children for HGG prior to RTX infusion, 59% during, and 52% following RTX treatment. Forty-seven percent had observed HGG prior to RTX administration, 61% during and 47% >9 months following treatment in 121, 210, and 128 subjects respectively. Thirty-three severe infections were reported among the cohort of 1328 RTX-treated subjects, of whom 3 children died. HGG had been recognized in 30/33 (80%) of them.

CONCLUSIONS

HGG in steroid-dependent/frequently relapsing nephrotic syndrome (SDNS/FRNS) children is probably multifactorial and can be observed prior to RTX administration in children with SDNS/FRNS. Persistent HGG lasting >9 months from RTX infusion is not uncommon and may increase the risk of severe infections in this cohort. We advocate for the obligatory screening for HGG in children with SDNS/FRNS prior to, during, and following RTX treatment. Further research is necessary to identify risk factors for developing both HGG and severe infections before recommendations are made for its optimal management. A higher resolution version of the Graphical abstract is available as Supplementary information.

[Diagnosis and therapy of granulomatosis with polyangiitis and microscopic polyangiitis-2023: consensus of the Austrian society of nephrology (ÖGN) and Austrian society of rheumatology (ÖGR)]

ANCA-associated vasculitides (AAV) are rare, complex systemic diseases that are often difficult to diagnose, because of unspecific clinical symptoms at presentation. However, the clinical course may be very dramatic and even life-threatening, necessitating prompt diagnosis and treatment.Therefore, it is important to increase disease awareness among physicians and support colleagues who are not confronted with these rare diseases on a regular basis. Here, the Austrian Society of Nephrology (ÖGN) and the Austrian Society of Rheumatology (ÖGR) provide a joint consensus on how to best diagnose and manage patients with granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA).

Infectious risk when prescribing rituximab in patients with hypogammaglobulinemia acquired in the setting of autoimmune diseases

We conducted a single-centre retrospective cohort study in a French University Hospital between 2010 and 2018 to describe the risk of severe infectious event (SIE) within 2 years after the date of first rituximab infusion (T0) prescribed after the evidence of acquired hypogammaglobulinemia (gamma globulins [GG] ≤ 6 g/L) in the setting of autoimmune diseases (AID) other than rheumatoid arthritis. SIE occurred in 26 out of 121 included patients. Two years cumulative incidence rates were 12.7 % (95 % CI 5.1-23.9) in the multiple sclerosis/neuromyelitis optica spectrum disorder group (n = 48), 27.6 % (95 % CI 15.7-40.9) in the ANCA-associated vasculitis group (n = 48) and 30.6 % (95 % CI 13.1-50.3) in the 'other AID' group (n = 25). Median GG level at T0 was 5.3 g/l (IQR 4.1-5.6) in the 'SIE' group and 5.6 g/l (IQR 4.7-5.8) in the 'no SIE' group (p = 0.04). In regression analysis, risk of SIE increased with Charlson comorbidity index ≥ 3 (OR 2.77; 95 % CI 1.01-7.57), lung disease (OR 3.20; 95 % CI 1.27-7.99), GG < 4 g/L (OR 3.39; 95 % CI 1.02-11.19), concomitant corticosteroid therapy (OR 4.13; 95 % CI 1.63-10.44), previous cyclophosphamide exposure (OR 2.69; 95 % CI 1.10-6.61), a lymphocyte count < 1000 cells/µL (OR 2.86; 95 % CI 1.12-7.21) and absence of pneumococcal vaccination (OR 3.50; 95 % CI 1.41-8.70). These results may help to inform clinical decision when considering a treatment by rituximab in immunosuppressed AID patients with hypogammaglobulinemia.

Use of Rituximab in Childhood Idiopathic Nephrotic Syndrome

Rituximab is an established therapy in children with idiopathic nephrotic syndrome to sustain short- to medium-term disease remission and avoid steroid toxicities. Recent trials focus on its use as a first-line agent among those with milder disease severity. Rituximab is used in multidrug refractory nephrotic syndrome and post-transplant disease recurrence, although the evidence is much less substantial. Available data suggest that the treatment response to rituximab depends on various patient factors, dosing regimen, and the concomitant use of maintenance immunosuppression. After repeated treatments, patients are found to have an improving response overall with a longer relapse-free period. The drug effect, however, is not permanent, and 80% of patients eventually relapse and many will require an additional course of rituximab. This underpins the importance of understanding the long-term safety profile on repeated treatments. Although rituximab appears to be generally safe, there are concerns about long-term hypogammaglobulinemia, especially in young children. Reliable immunophenotyping and biomarkers are yet to be discovered to predict treatment success, risk of both rare and severe side effects, e.g. , persistent hypogammaglobulinemia, and guiding of redosing strategy. In this review, we highlight recent advances in the use of rituximab for childhood nephrotic syndrome and how the therapeutic landscape is evolving.

SARS-CoV-2 vaccination willingness and predictors in patients with chronic inflammatory rheumatic diseases (CIRD) and without CIRD

Background

Recent surveys in chronic inflammatory rheumatic diseases (CIRD) showed a high degree of vaccine hesitancy. Current knowledge about patients' attitudes toward vaccination against SARS-CoV-2 is limited.

Objectives

To assess the willingness of CIRD patients to be vaccinated against SARS-CoV-2 and to identify the influencing factors compared with non-CIRD patients.

Methods

In this cross-sectional study, two cohorts of consecutive patients with and without CIRD were recruited in parallel when presenting to our tertiary hospital and asked to answer questions of a structured interview to assess vaccination willingness to SARS-CoV-2 their experience with SARS-CoV-2 and their personal history of infections and vaccinations. Vaccination willingness was assessed using a numerical rating scale (0: fully disagree; 10: fully agree). Arbitrarily defined cut-offs were used to define definite (score ⩾7) and probable willingness (score of 5 or 6) to be vaccinated. Factors associated with willingness were assessed using Kendall's tau-b correlation measure and linear regression analysis.

Results

A total of 514 CIRD and 100 non-CIRD patients, mean age of 54.7 ± 12.8 and 55.6 ± 9.8 years, respectively, were included. Definite and probable willingness to be vaccinated against SARS-CoV-2 was declared by 79.6% and 90.7% versus 76.0% and 85.0% of CIRD and non-CIRD patients, respectively. Only 60% of CIRD patients believed that the vaccines against SARS-CoV-2 were safe, and 42% indicated to be afraid of side effects. Vaccination willingness was significantly correlated with being in a risk group for COVID-19 (tau-b = -0.149), hypertension (tau-b = 0.14), and information about disease prevention (tau-b = 0.19), while a history of infections or immunosuppressive therapy was not. Vaccination willingness was significantly associated with higher education (b = 0.65) and age (b = 0.06).

Conclusion

This survey highlights several predictors of relevance for the vaccination willingness of patients with CIRD and controls including appropriate information about its relevance. The good news, however, is that the vast majority of CIRD patients indicated their willingness to be vaccinated. However, there was some uncertainty regarding the safety and efficacy of the vaccines. Since the major influencing factors were education and information about SARS-CoV-2 Vaccine and COVID-19 Disease, patient education should be improved soon.

Long-Term Efficacy and Safety of Repeated Rituximab to Maintain Remission in Idiopathic Childhood Nephrotic Syndrome: An International Study

BACKGROUND

Long-term outcomes after multiple courses of rituximab among children with frequently relapsing, steroid-dependent nephrotic syndrome (FRSDNS) are unknown.

METHODS

A retrospective cohort study at 16 pediatric nephrology centers from ten countries in Asia, Europe, and North America included children with FRSDNS who received two or more courses of rituximab. Primary outcomes were relapse-free survival and adverse events.

RESULTS

A total of 346 children (age, 9.8 years; IQR, 6.6-13.5 years; 73% boys) received 1149 courses of rituximab. A total of 145, 83, 50, 28, 22, and 18 children received two, three, four, five, six, and seven or more courses, respectively. Median (IQR) follow-up was 5.9 (4.3-7.7) years. Relapse-free survival differed by treatment courses (clustered log-rank test P<0.001). Compared with the first course (10.0 months; 95% CI, 9.0 to 10.7 months), relapse-free period and relapse risk progressively improved after subsequent courses (12.0-16.0 months; HRadj, 0.03-0.13; 95% CI, 0.01 to 0.18; P<0.001). The duration of B-cell depletion remained similar with repeated treatments (6.1 months; 95% CI, 6.0 to 6.3 months). Adverse events were mostly mild; the most common adverse events were hypogammaglobulinemia (50.9%), infection (4.5%), and neutropenia (3.7%). Side effects did not increase with more treatment courses nor a higher cumulative dose. Only 78 of the 353 episodes of hypogammaglobulinemia were clinically significant. Younger age at presentation (2.8 versus 3.3 years; P=0.05), age at first rituximab treatment (8.0 versus 10.0 years; P=0.01), and history of steroid resistance (28% versus 18%; P=0.01) were associated with significant hypogammaglobulinemia. All 53 infective episodes resolved, except for one patient with hepatitis B infection and another with EBV infection. There were 42 episodes of neutropenia, associated with history of steroid resistance (30% versus 20%; P=0.04). Upon last follow-up, 332 children (96%) had normal kidney function.

CONCLUSIONS

Children receiving repeated courses of rituximab for FRSDNS experience an improving clinical response. Side effects appear acceptable, but significant complications can occur. These findings support repeated rituximab use in FRSDNS.

Update on the treatment of steroid-sensitive nephrotic syndrome

Steroid-sensitive nephrotic syndrome (SSNS) is a rare condition that develops primarily in preadolescent children after the age of 1 year. Since the 1950s, oral corticosteroids have been the mainstay of treatment of all children presenting with nephrotic syndrome, with most patients responding within 4 weeks to an oral course of prednisone (PDN). However, corticosteroids have important side effects and 60-80 % of patients relapse, developing frequently relapsing or steroid-dependent forms. For these reasons, many patients require second-line steroid-sparing immunosuppressive medications that have considerably improved relapse-free survival, while avoiding many PDN-related toxicities. Since most patients will eventually heal from their disease with a normal kidney function, the morbidity of SSNS is primarily related to side effects of drugs that are used to maintain prolonged remission. Therefore, treatment is essentially based on balancing the use of different drugs to achieve permanent remission with the lowest cumulative number of side effects. Treatment choice is based on the severity of SSNS, on patient age, and on drug tolerability. This review provides an update of currently available therapeutic strategies for SSNS.

Rituximab Induction and Maintenance in ANCA-Associated Vasculitis: State of the Art and Future Perspectives

Antineutrophil cytoplasmatic antibody (ANCA)-associated vasculitis (AAV) is a group of rare autoimmune diseases characterized by inflammation of the vascular wall. The pathogenesis of AAV is strongly associated with B cell-derived ANCAs; thus, Rituximab (RTX) has become a promising drug in the induction and maintenance treatment of AAV. The purpose of this review is to describe the efficacy and safety of RTX in the induction of remission and maintenance therapy of AAV. Herein, we summarize the randomized controlled trials that have contributed to the refinement of the use of RTX in AAV in the past decades. RTX has been proven to be effective both in new-onset disease and in relapsing disease. Although the optimal duration of AAV maintenance therapy remains unknown, the ANCAs and the B-cell repopulation may offer support for the administration of further RTX cycles (or not). The safety of RTX is comparable with cyclophosphamide, with the advantage of a low risk of malignancy and no concern for fertility. In conclusion, RTX now plays an important role in the induction and maintenance therapy of AAV. Optimizing RTX-based treatment strategies in AAV is one of the main goals of the current research in AAV.

Rituximab-associated hypogammaglobulinemia in autoimmune rheumatic diseases: a single-center retrospective cohort study

B-cell targeted therapies, such as rituximab (RTX), are used widely in autoimmune rheumatic diseases (AIRD). RTX can cause hypogammaglobulinemia and predispose patients to infections. Herein, we asked whether the underlying diagnosis influences the risk for hypogammaglobulinemia in patients treated with RTX. All patients who received RTX infusions and carried a diagnosis of rheumatoid arthritis (RA), ANCA-associated vasculitis (AAV), or connective tissue disease (CTD) were included in this single-center retrospective cohort study. We used STATA® for analysis: Chi-square test was used for comparing categorical variables. Based on distribution, continuous variables were compared using the t test/ANOVA or the Wilcoxon/Kruskal-Wallis tests. Of the 163 patients who received RTX for an AIRD, 60 with pre- and post- RTX immunoglobulins were analyzed. A higher incidence of post-treatment hypogammaglobulinemia was seen in AAV (45%) compared to RA (22%) and CTD (9.1%) groups (p = 0.03). Glucocorticoid exposure of 10 mg or more was identified as a significant risk factor for hypogammaglobulinemia. Finally, we observed a higher number of clinically significant infections per person in the AAV group than in the RA and CTD groups. We observed an increased incidence of hypogammaglobulinemia in the RTX-treated AAV group, with almost half of patients developing post-RTX hypogammaglobulinemia. The rate of infections per person was highest in the AAV group. Screening immunoglobulins were not consistently measured pre- and post-RTX. Results highlight a need for increased awareness of the role of immunoglobulin measurement before maintenance doses of RTX, especially in patients with AAV and steroid exposure.

Rituximab in children with steroid sensitive nephrotic syndrome: in quest of the optimal regimen

Rituximab has emerged as an effective and important therapy in children with complicated frequently relapsing and steroid-dependent nephrotic syndrome to induce long-term disease remission and avoid steroid toxicities. The optimal rituximab regimen is not totally well defined, and there are many varying practices worldwide. We will in this review describe how patient factors, rituximab dose, and use of maintenance immunosuppression affect treatment outcomes. Specifically, low-dose rituximab without concomitant immunosuppression is associated with shorter relapse-free duration while other regimens have comparable outcomes. Patients with more severe disease generally have worse response to rituximab. Although rituximab appears to be generally safe, there are growing concerns of chronic hypogammaglobulinemia and impaired immunity especially in young children. Reliable prognostications and biomarkers for guiding subsequent treatments to avoid excessive treatments are yet to be identified. In this review, we will outline the, as we see it, best approach of rituximab in childhood steroid sensitive nephrotic syndrome at the present state of knowledge.

Serious Infectious Events and Immunoglobulin Replacement Therapy in Patients With Autoimmune Disease Receiving Rituximab: A Retrospective Cohort Study

BACKGROUND

Rituximab (RTX) is widely administered to patients with autoimmune disease (AID). This study aimed to estimate the incidence of serious infectious events (SIEs) after RTX initiation in patients with AID. We also described the characteristics and risk factors of SIEs, and immunoglobulin replacement therapy (IgRT) strategies.

METHODS

Patients treated between 2005 and 2016 were included in this retrospective monocentric cohort study. An RTX course was defined as the complete RTX treatment regimen received by a given patient for AID. SIEs and IgRT were right-censored at 24 months after RTX initiation.

RESULTS

Two hundred twenty-one patients were included (corresponding to 276 RTX courses). Reasons for RTX initiation included connective tissue disease (38%), systemic vasculitis (36%), and autoimmune cytopenia (22%). The 1- and 2-year incidences of SIEs were 17.3 (95% confidence interval [CI], 12.0-22.5) and 11.3 (95% CI, 8.1-14.5) per 100 person-years, respectively. Forty-seven SIEs were observed, mostly comprising pneumonias (45%) and bacteremias (21%). When documented, the microorganisms were bacterial (55%) and fungal (12%). Identified risk factors of SIEs were age, history of diabetes, history of cancer, concomitant steroid treatment, and low CD4 lymphocyte count at RTX initiation. IgRT was started in 22 RTX courses (8%).

CONCLUSIONS

In patients with AID treated with RTX, the 1- and 2-year incidence of SIE was 17.3 and 11.3 per 100 person-years, respectively. Reports of SIE characteristics, risk factors, and IgRT strategies highlight the need for an appropriate and individualized assessment prior to and following RTX to prevent SIEs, particularly in patients with comorbidities.

B Cell Dysregulation in Common Variable Immunodeficiency Interstitial Lung Disease

Common variable immunodeficiency (CVID) is the most frequently diagnosed primary antibody deficiency. About half of CVID patients develop chronic non-infectious complications thought to be due to intrinsic immune dysregulation, including autoimmunity, gastrointestinal disease, and interstitial lung disease (ILD). Multiple studies have found ILD to be a significant cause of morbidity and mortality in CVID. Yet, the precise mechanisms underlying this complication in CVID are poorly understood. CVID ILD is marked by profound pulmonary infiltration of both T and B cells as well as granulomatous inflammation in many cases. B cell depletive therapy, whether done as a monotherapy or in combination with another immunosuppressive agent, has become a standard of therapy for CVID ILD. However, CVID is a heterogeneous disorder, as is its lung pathology, and the precise patients that would benefit from B cell depletive therapy, when it should administered, and how long it should be repeated all remain gaps in our knowledge. Moreover, some have ILD recurrence after B cell depletive therapy and the relative importance of B cell biology remains incompletely defined. Developmental and functional abnormalities of B cell compartments observed in CVID ILD and related conditions suggest that imbalance of B cell signaling networks may promote lung disease. Included within these potential mechanisms of disease is B cell activating factor (BAFF), a cytokine that is upregulated by the interferon gamma (IFN-γ):STAT1 signaling axis to potently influence B cell activation and survival. B cell responses to BAFF are shaped by the divergent effects and expression patterns of its three receptors: BAFF receptor (BAFF-R), transmembrane activator and CAML interactor (TACI), and B cell maturation antigen (BCMA). Moreover, soluble forms of BAFF-R, TACI, and BCMA exist and may further influence the pathogenesis of ILD. Continued efforts to understand how dysregulated B cell biology promotes ILD development and progression will help close the gap in our understanding of how to best diagnose, define, and manage ILD in CVID.

[Biologicals and small molecules for rheumatoid arthritis]

In recent years tremendous progress has been made in the therapeutic management of rheumatoid arthritis. Rheumatologists now have a large armamentarium of highly efficient drugs with different mechanisms of action at their disposal. These new drugs consist of biologicals (biological disease-modifying antirheumatic drugs, bDMARDs) as well as targeted synthetic DMARDs (tsDMARD). A common feature of these new drugs for treatment of rheumatoid arthritis is that the molecular target of the drug is known, which is not the case for conventional DMARDs. With the help of the new drugs, the therapeutic goal of inducing remission in patients with rheumatoid arthritis has become reality for many patients. Nevertheless, there is still a significant proportion of patients who do not adequately respond to all available drugs, leaving room for still further improvement. This review gives a short overview on the currently available and effective substances for the treatment of rheumatoid arthritis.

Prevention Strategies to Minimize the Infection Risk Associated with Biologic and Targeted Immunomodulators

The introduction of biologic and targeted immunomodulators is a significant breakthrough in the therapeutic area of various fields of medicine. The occurrence of serious infections, a complication of secondary immunosuppression associated with these agents, leads to increased morbidity and mortality. Implementing preventive strategies could minimize infection-related complications and improve therapeutic outcomes. The purpose of this review is to focus on current evident approaches regarding screening, monitoring, preventing (immunization and chemoprophylaxis), and management of infections in patients who are candidates for about 70 biologic and targeted immunomodulators. Recommendations are based on relevant guidelines, especially the ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document series published in 2018.

Serum B-Cell Maturation Antigen (BCMA) Levels Differentiate Primary Antibody Deficiencies

BACKGROUND

Primary antibody deficiencies (PADs) are the most prevalent primary immunodeficiencies. More severe forms of PADs-common variable immunodeficiency (CVID) and X-linked agammaglobulinemia (XLA)-require immunoglobulin replacement therapy (IRT) and may have serious complications. Differentiating severe PAD from milder hypogammaglobulinemia not requiring IRT can involve prolonged evaluations and treatment discontinuation. Severe PAD is defined by plasma cell deficiency, but this requires a biopsy to establish. Serum B-cell maturation antigen (sBCMA) is elevated in multiple myeloma, but levels are reduced among patients with myeloma in remission who have hypogammaglobulinemia.

OBJECTIVE

To measure the sBCMA level in 165 subjects to determine whether it differentiates severe PAD-CVID and XLA-from less severe forms not requiring IRT and those without PAD.

METHODS

sBCMA, B cells, and tissue plasma cells were measured among subjects with and without PAD, and correlated to clinical and laboratory data.

RESULTS

Subjects with an IgG level of less than 600 mg/dL had reduced sBCMA levels compared with subjects with PAD with IgG levels of greater than or equal to 600 mg/dL and controls without PAD. sBCMA level was lower in patients with CVID and XLA compared with patients with IgA or IgG deficiency and controls. sBCMA level correlated with gastrointestinal plasma cells. sBCMA level of less than 15 ng/mL had 97% positive predictive value for CVID or XLA, whereas 25 ng/mL or more had an 88% negative predictive value.

CONCLUSIONS

sBCMA level is profoundly reduced in patients with severe PAD, including those with CVID and XLA and those with IgG levels of less than 600 mg/dL. sBCMA level measurement has potential to augment clinical evaluation of PAD. Prospective studies are needed to evaluate sBCMA for new PAD diagnosis and determine the necessity of IRT.

Predicting Severe Infection and Effects of Hypogammaglobulinemia During Therapy With Rituximab in Rheumatic and Musculoskeletal Diseases

OBJECTIVE

To evaluate predictors of serious infection events (SIEs) during rituximab (RTX) therapy and effects of hypogammaglobulinemia on SIE rates, and humoral response and its persistence after discontinuation of RTX in the treatment of rheumatic and musculoskeletal diseases (RMDs).

METHODS

A retrospective longitudinal study of 700 RMD patients treated with RTX in a single center was conducted. Immunoglobulin levels were measured at baseline and at 4-6 months after each treatment cycle. Baseline predictors of SIEs were assessed using multivariable logistic regression; for RTX cycles 2-4, a mixed-effects logistic regression model was used.

RESULTS

A total of 507 patients (72%) had rheumatoid arthritis, 94 (13%) had systemic lupus erythematosus, 49 (7%) had antineutrophil cytoplasmic antibody-associated vasculitis, and 50 (7%) had other RMDs. The number of SIEs recorded was 281 in 176 patients (9.8 per 100 person-years). Predictors of SIEs included non-RTX-specific comorbidities (previous history of SIE, cancer, chronic lung disease, diabetes mellitus, and heart failure), higher corticosteroid dose, and RTX-specific factors, including low IgG (<6 gm/liter) both at baseline and during treatment, RTX-associated neutropenia, higher IgM, and longer time to RTX re-treatment, but not B cell count or depletion status. Of 110 patients with low IgG, SIE rates were higher in those with low IgG at baseline (16.4 per 100 person-years) and in those who acquired low IgG during or after RTX treatment (21.3 per 100 person-years) versus those with normal IgG (9.7 per 100 person-years). Five of 8 patients (63%) had impaired humoral response to pneumococcus and hemophilus following vaccination challenge, and only 4 of 11 patients (36%) had IgG normalized after switching biologic disease-modifying antirheumatic drugs.

CONCLUSION

Immunoglobulin levels should be monitored at baseline and before each RTX cycle to identify patients at risk of SIEs. Individualized risk-benefit assessment should be undertaken in those with lower IgG as this is a consistent SIE predictor and may increase infection profiles when RTX is switched to different therapies.

Immunoglobulin abnormalities are frequent in patients with lupus nephritis

Background

Hypogammaglobulinemia is a complication of B-cell targeting therapies (BCTT), used in vasculitis, rheumatoid arthritis and systemic lupus erythematosus (SLE). Since autoimmune diseases are associated with underlying and induced immune abnormalities, several societies recommend assessing immune function before and during rituximab treatment. In SLE, polyclonal hypergammaglobulinemia is the typical alteration of gammaglobulins, though hypogammaglobulinemia has also been reported.

Methods

This is a cross-sectional study describing immunoglobulin levels measured as part of routine care in patients with lupus nephritis, a group with multiple factors contributing to immunoglobulin abnormalities, including immune dysregulation, immunosuppression and nephrotic syndrome.

Results

Polyclonal hypergammaglobulinemia occurred in 15/83 (18.1%) patients. In contrast, low levels of immunoglobulins were found as follows: selective IgA deficiency 2/83 (2.4%), reduced IgG levels 7/83 (8.4%), reduced IgM 14/83 (16.9%). Only 1 patient required immunoglobulin replacement.

Conclusions

Immunoglobulin abnormalities are frequently found in lupus nephritis, ranging from polyclonal hypergammaglobulinemia to hypogammglobulinemia. Consequently, immunoglobulin levels should be assessed prior to commencing BCTT.