Treatment Updates in Antineutrophil Cytoplasmic Autoantibodies (ANCA) Vasculitis

Critically Ill Patients with Newly Diagnosed Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis: Case Series and Literature Review

ANCA-associated vasculitides (AAVs) are rare diseases with a prevalence of less than 200 cases per million persons and an incidence of less than 25 cases per million person-years. Their presenting features can vary from prodromal and nonspecific symptoms to dramatic organ-specific symptoms such as respiratory failure due to diffuse alveolar hemorrhage (DAH) and acute kidney injury (AKI). The latter two are hallmark features of pulmonary-renal syndrome, a potentially fatal condition that necessitates early recognition and treatment in intensive care units (ICUs) and rapid induction of immunosuppressive therapy. Background and case summaries: We described three patients with newly diagnosed AAV during the treatment of critical illness. All patients had DAH and two had AKI. The initial disease severity was extremely high in patients with myeloperoxidase (MPO)-AAV, reaching Sequential Organ Failure Assessment (SOFA) scores of 15 and 14 with predicted mortality ≥ 95.2%. Both patients needed mechanical ventilation, one additional venovenous extracorporeal membrane oxygenation (VV-ECMO), and renal replacement therapy. The patient with proteinase 3 (PR3)-AAV had a less severe disease, SOFA 3, requiring only modest oxygen supplementation and exhibiting only hematuria with normal renal function parameters. Immunosuppressive therapy was initiated during the ICU stay. The patient with the most severe clinical presentation died during the ICU stay because of sepsis, and the other two patients were discharged home. Conclusions: Patients with AAV presenting with pulmonary-renal syndrome necessitate various degrees of organ support. Nevertheless, these patients can be successfully treated in the early, critical stages of the disease and achieve remission.

Antineutrophil Cytoplasmic Antibodies Associated Vasculitis Presenting As Neuropathy

Antineutrophil cytoplasmic antibody-related vasculitis (AAV), is a group of diseases marked by systemic symptoms and severe small vessel inflammation. The three subtypes of AAV are eosinophilic GPA (EGPA), Microscopic Polyangiitis (MPA), and Granulomatosis with Polyangiitis (GPA). The organs that get involved in the disease process are the kidneys and the upper and lower respiratory tracts, with a spectrum of neurological manifestations. Here, we present a case report of a 68-year-old man who came with complaints of tingling and numbness over bilateral lower limbs for two months accompanied by difficulty in walking and bilateral foot drop without any respiratory complaints or involvement of sensory or autonomic system who was diagnosed with AAV (c-ANCA +) on further workup. A sural Nerve biopsy was done for confirmation which was suggestive of chronic, asymmetrical axonal neuropathy with perivascular inflammation, suggestive of vasculitic neuropathy. The patient had no other organ involvement. The patient was started on glucocorticoids and cyclophosphamide therapy for 6 cycles after which his symptoms and quality of life improved drastically.

Invasive fungal infection in ANCA-associated vasculitis: Between the Devil and Deep blue sea. Case series and review of the literature

INTRODUCTION

Patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV) are susceptible to opportunistic infections, including invasive fungal infections (IFI). This is due to many factors, including prolonged immunosuppressive therapy. The treatment of AAV with such IFIs is challenging.

METHODS

A descriptive analysis of 5 patients with AAV complicated by concomitant invasive fungal infections was performed. We also have done a comprehensive literature review of IFIs in AAV using PubMed and Google Scholar databases.

RESULTS

All 5 patients initially received immunosuppressive medication but subsequently acquired IFI. One patient had sphenoid sinus involvement, and four had lung parenchymal involvement. Aspergillus infection was diagnosed in three patients, Cryptococcus infection in one patient and mixed infection with Aspergillus and Mucor infection in one patient. All our patients were on low doses of corticosteroids for several months to years or had received high-dose pulse steroids with cyclophosphamide in the last few weeks before being diagnosed with IFI. It was difficult to distinguish disease activity from IFI in all the cases. Two of the five patients died despite antifungal therapy. The literature review revealed a prevalence of IFIs ranging from 1 to 9.6% (excluding pneumocystis pneumonia). Aspergillosis was the predominant type of IFI, affecting 46 of 86 patients. Most of these patients (40/46) had pulmonary involvement. The prognosis for patients with IFI was consistently poor, as evidenced by 19 deaths out of 29 reported outcomes.

CONCLUSION

Overall, IFIs have a poor prognosis in patients with AAV. Differentiating disease activity from IFI is difficult because of similar organ distribution, imaging lesions, and histopathological characteristics. A high suspicion index and good-quality microbiology are needed for early treatment and prevention of mortality.

ANCA detection with solid phase chemiluminescence assay: diagnostic and severity association in vasculitis

ANCA-associated vasculitis (AAV) comprises a group of necrotizing vasculitis that mainly affects small- and medium-sized vessels. Serum anti-neutrophil cytoplasmic antibodies (ANCA), mainly anti-myeloperoxidase (anti-MPO) and anti-proteinase 3 (anti-PR3), levels may correlate to severity, prognosis, and recurrence of the disease. A retrospective analysis of 101 patients with MPO-positive and 54 PR3-positive vasculitis was performed, using laboratory established cut-off value, measured by chemiluminescence. Furthermore, data of renal disease and pulmonary involvement were collected at vasculitis diagnosis, as well as the progress, requiring dialysis, transplant, or mortality. For anti-MPO antibodies with a diagnosis of vasculitis (n = 77), an area under the curve (AUC) was calculated (AUC = 0.8084), and a cut-off point of 41.5 IU/ml was determined. There were significant differences in anti-MPO levels between patients with renal or pulmonary dysfunction (n = 65) versus those without them (n = 36) (p = 0.0003), and a cut-off threshold of 60 IU/ml was established. For anti-PR3 antibodies with a diagnosis of vasculitis (n = 44), an area under the curve (AUC) was calculated (AUC = 0.7318), and a cut-off point of 20.5 IU/ml was determined. Significant differences in anti-PR3 levels were observed between those patients with renal or pulmonary dysfunction (n = 30) and those without them (n = 24) (p = 0.0048), and a cut-off threshold of 41.5 IU/ml was established. No significant differences between those patients who had a worse disease progression and those who did not were found for anti-MPO and anti-PR3. Anti-MPO and anti-PR3 levels at the moment of vasculitis diagnosis are related with disease severity but not with disease outcome or vasculitis recurrence.

The Meteoritics Trial: efficacy of methotrexate after remission-induction with tocilizumab and glucocorticoids in giant cell arteritis-study protocol for a randomized, double-blind, placebo-controlled, parallel-group phase II study

BACKGROUND

Glucocorticoids (GC) are the standard treatment for giant cell arteritis (GCA), even though they are associated with adverse side effects and high relapse rates. Tocilizumab (TCZ), an interleukin-6 receptor antagonist, has shown promise in sustaining remission and reducing the cumulative GC dosage, but it increases the risk of infections and is expensive. After discontinuation of TCZ, only about half of patients remain in remission. Additionally, only few studies have been conducted looking at remission maintenance, highlighting the need for alternative strategies to maintain remission in GCA. Methotrexate (MTX) has been shown to significantly decrease the risk of relapse in new-onset GCA and is already a proven safe drug in many rheumatologic diseases.

METHODS

This study aims to evaluate the efficacy and safety of MTX in maintaining remission in patients with GCA who have previously been treated with GC and at least 6 months with TCZ. We hypothesize that MTX can maintain remission in GCA patients, who have achieved stable remission after treatment with GC and TCZ, and prevent the occurrence of relapses. The study design is a monocentric, randomized, double-blind, placebo-controlled, parallel-group phase II trial randomizing 40 GCA patients 1:1 into a MTX or placebo arm. Patients will receive 17.5 mg MTX/matching placebo weekly by subcutaneous injection for 12 months, with the possibility of dose reduction if clinically needed. A 6-month follow-up will take place. The primary endpoint is the time to first relapse in the MTX group versus placebo during the 12-month treatment period. Secondary outcomes include patient- and investigator-reported outcomes and laboratory findings, as well as the prevalence of aortitis, number of vasculitic vessels, and change in intima-media thickness during the study.

DISCUSSION

This is the first clinical trial evaluating remission maintenance of GCA with MTX after a previous treatment cycle with TCZ. Following the discontinuation of TCZ in GCA, MTX could be a safe and inexpensive drug.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT05623592. Registered on 21 November 2022. EU Clinical Trials Register, 2022-501058-12-00. German Clinical Trials Register DRKS00030571.

Kv1.3 blockade by ShK186 modulates CD4+ effector memory T-cell activity of patients with granulomatosis with polyangiitis

OBJECTIVES

Granulomatosis with polyangiitis (GPA) is a chronic relapsing systemic autoimmune vasculitis. Current treatment of GPA is unsatisfactory, as it relies on strong immunosuppressive regimens, with either CYC or rituximab, which reduce the immunogenicity of several vaccines and are risk factors for a severe form of COVID-19. This emphasizes the need to identify new drug targets and to develop treatment strategies with less harmful side effects. Since CD4+ effector memory T cells (TEM) play a key role in the pathogenesis of GPA, we aimed in this study to modulate CD4+TEM cell activity via Kv1.3 blockade using the specific peptide inhibiter, ShK-186.

METHODS

Peripheral blood samples from 27 patients with GPA in remission and 16 age- and sex-matched healthy controls (HCs) were pre-incubated in vitro in the presence or absence of ShK-186, followed by stimulation with phorbol myristate acetate, calcium ionophore and brefeldin-A. The effect of ShK-186 on the cytokine production (IFNγ, TNFα, IL-4, IL-17, IL-21) within total and subsets of CD4+ T helper (CD4+TH) cells were assessed using flow cytometry.

RESULTS

ShK-186 reduced the expression level of IFNγ, TNFα, IL-4, IL-17 and IL-21 in CD4+TH cells from patients with GPA in vitro. Further analysis performed on sorted CD4+T cell subsets, revealed that ShK-186 predominantly inhibited the cytokine production of CD4+TEM cells. ShK-186 treatment reduced the production of the pro-inflammatory cytokines to the level seen in CD4+ TH cells from HCs.

CONCLUSIONS

Modulation of cellular effector function by ShK-186 may constitute a novel treatment strategy for GPA with high specificity and less harmful side effects.

A case of anti-neutrophil cytoplasmic antibody-associated vasculitis masquerading as Sjögren syndrome

Anti-neutrophil cytoplasmic antibody (ANCA) -positive vasculitis is a small-vessel vasculitis that affects multiple body systems. Salivary gland involvement in ANCA-associated vasculitis is rare. When present, it mimics infection or malignancy, which might lead to misdiagnosis. In this report, we describe a 72-year-old man who presented with parotid and submandibular gland pain and swelling in addition to dry mouth and eyes. He had bilateral non-tender parotid gland lumps and no lymphadenopathies. Laboratory tests were positive for ANCA, hematuria, and proteinuria but negative for Anti-Ro and -La. He was treated with corticosteroids and cyclophosphamide for acute kidney injury. Unfortunately, the patient died a few months later. This case report sheds light on a rare manifestation of salivary gland involvement in ANCA-associated vasculitis that mimics Sjögren syndrome and the challenges associated with its diagnosis and treatment.

Low-Dose Intravenous Methylprednisolone in Remission Induction Therapy for ANCA-Associated Vasculitis

Key Points

The contribution of IV methylprednisolone to glucocorticoid toxicity is often overlooked with limited evidence supporting its use. Markedly reduced cumulative glucocorticoid dosing for remission induction therapy in AAV is safe and effective. Reduced IV methylprednisolone and radical steroid avoidance strategies have not been shown to have any significant adverse effect on outcomes.

Background

Glucocorticoids (GCs) remain integral to the management of ANCA-associated vasculitis (AAV), but are associated with significant adverse effects. Recent studies have shown reduced oral GC dosing to be safe and effective; however, data guiding the use of intravenous (IV) methylprednisolone (MTP) are limited.

Method

A single-center retrospective cohort of patients with AAV were divided into two groups: low-dose GC (patients receiving 250 mg of IV MTP, followed by a tapering course of 30 mg of prednisolone daily) versus high-dose GC (1.5 g of IV MTP, followed by a tapering course of 40–60 mg of prednisolone daily). Primary outcomes included ESKD and mortality, and secondary outcomes included GC-related toxicity, remission, and relapse rates. This study was applied to patients with newly diagnosed AAV, including those with severe or life-threatening disease.

Results

Sixty-five patients were included in the final analysis—34 in the high-dose treatment group and 31 in the low-dose treatment group. At diagnosis, more advanced renal impairment and histological disease were present in the low-dose cohort. The rate of ESKD was similar between the groups at 6 and 12 months (P = 0.22, P = 0.60, respectively). More deaths occurred in the high-dose group (26.5% versus 6.5%, P = 0.05), although this was not significant on multivariable analysis (P = 0.06). Remission rates were comparable, and there was no significant difference in relapses. Adverse events were seen in both groups, but patients in the high-dose group experienced a higher incidence of severe infections, weight gain, and steroid-induced diabetes.

Conclusion

We demonstrate that a markedly reduced dose of IV MTP with a lower overall cumulative dose of GCs is safe and effective in the management of severe AAV disease, with no significant difference in primary outcomes.

Optimal management of ANCA-associated vasculitis before and during pregnancy: current perspectives

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are a group of systemic vasculitis characterized by autoantibodies against neutrophil cytoplasmic antigens (proteinase 3 PR3-ANCA and myeloperoxidase MPO-ANCA) and inflammation of small vessels. AAV include the diagnosis Granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA), which share many clinical and pathological features. Immunomodulatory therapies have significantly improved prognosis during the last decade. Nevertheless, especially in undiagnosed and thus uncontrolled AAV mortality due to renal impairment or pulmonary haemorrhages is still high. AAV are rare in fertile women, as the typical age of manifestation is above 50 years but there are women with AAV who are or want to become pregnant. This review focusses on how to manage patients with AAV planning to become pregnant and during their pregnancy.

Complement therapeutics are coming of age in rheumatology

The complement system was described over 100 years ago, and it is well established that activation of this pathway accompanies the great majority of autoimmune and inflammatory diseases. In addition, over three decades of work in murine models of human disease have nearly universally demonstrated that complement activation is upstream of tissue injury and the engagement of pro-inflammatory mechanisms such as the elaboration of cytokines and chemokines, as well as myeloid cell recruitment and activation. With that background, and taking advantage of advances in the development of biologic and small-molecule therapeutics, the creation and clinical evaluation of complement therapeutics is now rapidly expanding. This article reviews the current state of the complement therapeutics field, with a focus on their use in diseases cared for or consulted upon by rheumatologists. Included is an overview of the activation mechanisms and components of the system, in addition to the mechanisms by which the complement system interacts with other immune system constituents. The various therapeutic approaches to modulating the system in rheumatic and autoimmune diseases are reviewed. To understand how best to clinically assess the complement system, methods of its evaluation are described. Finally, next-generation therapeutic and diagnostic advances that can be envisioned for the future are discussed.

The Diagnostic Conundrum of Glomerular Crescents With IgA Deposits

Introduction

Glomerulonephritis (GN) with crescents and IgA deposits in kidney biopsy poses a frequent diagnostic and therapeutic dilemma because of multiple possibilities.

Methods

Native kidney biopsies showing glomerular IgA deposition and crescents (excluding lupus nephritis) were identified from our biopsy archives between 2010 and 2021. Detailed clinicopathologic features were assessed. One-year clinical follow-up on a subset of cases was obtained.

Results

A total of 285 cases were identified, and these clustered into IgA nephropathy (IgAN, n = 108), Staphylococcus or other infection-associated GN/infection-related GN (SAGN/IRGN, n = 43), and antineutrophil cytoplasmic antibody-associated GN (ANCA-GN, n = 26) based on a constellation of clinicopathologic features, but 101 cases (group X) could not be definitively differentiated. The reasons have been elucidated, most important being atypical combination of clinicopathologic features and lack of definitive evidence of active infection. Follow-up (on 72/101 cases) revealed that clinicians' working diagnosis was IgAN in 43%, SAGN/IRGN in 22%, ANCA-GN in 28%, and others in 7% of the cases, but treatment approach varied from supportive or antibiotics to immunosuppression in each subgroup. Comparing these cases as "received immunosuppression" versus "non-immunosuppression," only 2 features differed, namely C3-dominant staining, and possibility of recent infection (both higher in the no-immunosuppression group) (P < 0.05). Renal loss was higher in the non-immunosuppression subgroup, but not statistically significant (P = 0.11).

Conclusion

Diagnostic overlap may remain unresolved in a substantial number of kidney biopsies with glomerular crescents and IgA deposits. A case-by-case approach, appropriate antibiotics if infection is ongoing, and consideration for cautious immunosuppressive treatment for progressive renal dysfunction may be needed for best chance of renal recovery.

Contributions of animal models to mechanistic understandings of antibody-dependent disease and roles of the amplification loop

The complement system plays an important pathophysiologic role in human diseases associated with immune or ischemic insults. In addition to understanding the effector mechanisms that are important for the biological effects of the system, substantial efforts have gone into understanding which specific complement activation pathways generate these potent effects. These approaches include the use of gene-targeted mice and specific pathway inhibitors, as well as the integration of human disease genetic and biomarker studies. In some disease states, it is quite clear that the alternate pathway plays a unique role in the initiation of the complement system. However, although initially a widely unexpected finding, it has now been shown in many tissue-based disease models and in initial human studies that engagement of the amplification loop is also essential for tissue injury when the classical and/or lectin pathways initiate pathway activation through pathogenic autoantibodies. This review provides evidence for such a conclusion through animal models, focusing on pathogenic antibody passive transfer models but also other relevant experimental systems. These data, along with initial biomarkers and clinical trial outcomes in human diseases that are associated with pathogenic autoantibodies, suggest that targeting the alternative pathway amplification loop may have near-universal therapeutic utility for tissue-based diseases.

The frequency of Treg subsets distinguishes disease activity in ANCA vasculitis

Objectives

T regulatory cells (Tregs) are a heterogeneous group of immunoregulatory cells that dampen self-harming immune responses and prevent the development of autoimmune diseases. In anti-neutrophil cytoplasmic autoantibody (ANCA) vasculitis, Tregs possess diminished suppressive capacity, which has been attributed to the expression of a FOXP3 splice-variant lacking exon 2 in T cells (FOXP3Δ2 CD4+ T cells). However, the suppressive capacity of Tregs varies between subsets. We evaluated the frequency of Treg subsets in ANCA vasculitis as a potential explanation for diminished suppressive capacity.

Methods

We developed a custom mass cytometry panel and performed deep immune profiling of Tregs in healthy controls, patients with active disease and in remission. Using these data, we performed multidimensional reduction and discriminant analysis to identify associations between Treg subsets and disease activity.

Results

Total Tregs were expanded in ANCA vasculitis, which was associated with remission and the administration of rituximab and/or prednisone. The frequency of FOXP3Δ2 CD4+ T cells did not distinguish disease activity and this population had high expression levels of CD127 and lacked both CD25 and Helios, suggesting that they are not conventional Tregs. The frequency of CXCR3+, CD103+ and CCR7+ Tregs distinguished disease activity, and the combination of the frequency of these three Treg subsets segregated active patients from patients in remission and healthy controls. From these three subsets, the frequency of CXCR3+ Tregs distinguished patients with active disease with renal involvement.

Conclusion

Treg heterogeneity can discriminate disease activity and should be explored as a biomarker of disease activity in ANCA vasculitis.

SARS-CoV-2 Infection: A Forerunner or Precursor in Anti-neutrophil Cytoplasmic Antibody-Associated Vasculitis With Kidney Injury

COVID-19 disease and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis are both multi-systemic conditions. It is postulated there is a causal relationship between both conditions and this is supported by some case reports. The symptoms of COVID-19 can mimic those of vasculitis especially when the respiratory system is affected. Early diagnosis and treatment of ANCA-vasculitis cannot be overemphasized as this reduces the risk of severe organ damage. We report a 64-year-old lady with SARS-CoV-2 infection who developed ANCA-vasculitis with acute kidney injury and we reviewed the literature on this plausible association.

We performed an electronic search of the MEDLINE, EMBASE, CINAHL, and EMCARE databases for research studies and case series and reports published in the English language between April 2020 and February 2022. Our review suggests that patients with COVID-19 infection who had proteinase 3-ANCA positive vasculitis with diffuse alveolar haemorrhage had fatal outcomes. We also noticed an increased incidence of active urine sediments. We emphasize the importance of a high index of suspicion for diagnosis and early treatment of vasculitis to ensure an improved outcome.

Recent Advancements in the Management of Anti-neutrophil Cytoplasmic Antibody-Associated Vasculitis: A Systematic Review

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a rare multisystem autoimmune condition that causes inflammation of small and medium-sized blood vessels and is more commonly seen in the geriatric population. ANCA-associated vasculitis (AAV) is typically characterized as necrotizing vasculitis and includes granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). The mortality rate remains high, with especially cardiovascular disease, infections, and malignancies being the leading causes of death. Existing treatment options depend heavily on the use of glucocorticoids (GCs), often in combination with cyclophosphamide (CYC); however, as the multitude of adverse effects associated with these agents has increased, numerous studies are being conducted to reduce not only these harmful effects but also improve remission rates. Rituximab, avacopan, corticosteroids, including intravenous pulse methylprednisolone, plasma exchange, and immunological targeting are among the emerging treatments. The purpose of this review is to emphasize the pathogenesis and traditional treatment modalities and give insights into the recent advances in managing this disorder in an attempt to spare the adverse effects of conventional therapies while achieving better remission rates with combination therapies as well. The authors explored multiple databases, employing appropriate keywords, satisfying the quality appraisal, after which a total of 14 reports were included in this review. Upon overall analysis, it can be concluded that rituximab and CYC, when used in combination, provided a safer alternative to GCs while exhibiting equal, if not superior, effectiveness and results, thus, paving the way for additional in-depth research in a larger population of interest.