Systematic Review and Metaanalysis of Worldwide Incidence and Prevalence of Antineutrophil Cytoplasmic Antibody (ANCA) Associated Vasculitis

Outcomes in Mexican Patients With Antineutrophil Cytoplasmic Antibody-Associated Vasculitis With Kidney Involvement

BACKGROUND/OBJECTIVE

This study assessed the outcomes of patients with antineutrophil cytoplasm antibody-associated vasculitis glomerulonephritis (AAV-GN).

METHODS

This historical cohort study included patients with AAV-GN evaluated from 2000 to 2022. The outcomes included recovery of kidney function from kidney replacement therapy, incidence of kidney relapses, and early or late progression to kidney failure. All outcomes were assessed by time-to-event analyses, and predictors were evaluated through Cox proportional hazards regression.

RESULTS

Among 154 patients, 104 (68%) were female with a median age of 52 years (interquartile range [IQR], 38-61 years). The median creatinine and estimated glomerular filtration rate at presentation were 2.5 mg/dL (IQR, 1.8-4.5 mg/dL) and 23 mL/min per 1.73 m2 (IQR, 12-36 mL/min per 1.73 m2), respectively. Fifty patients (32%) initially required kidney replacement therapy, with 22 (44%) of them subsequently recovering kidney function. Higher serum creatinine and a lower percentage of normal glomeruli were associated with lower rates of kidney function recovery. The kidney relapse rate was 24.9% by 5 years and 31.4% by 7 years. Proteinase 3-antineutrophil cytoplasm antibody positivity, kidney function, and persistent hematuria were associated with relapses. Kidney failure rates were 19.6% by 1 year and 30.5% by 5 years. Higher serum creatinine and proteinuria and a lower percentage of normal glomeruli were associated with higher rates of early kidney failure. Kidney relapses, persistent proteinuria, and kidney function posttreatment were associated with higher rates of late kidney failure.

CONCLUSIONS

The parameters at presentation of an episode of AAV-GN (creatinine, proteinuria, percentage of normal glomeruli) associate with progression to kidney failure within the first year. However, progression to kidney failure after the first year depends on posttreatment parameters and kidney relapses.

Epidemiology of systemic vasculitis

PURPOSE OF REVIEW

Ongoing research contributes to our understanding of the epidemiology of vasculitis and its outcomes across the globe. This review aims to summarize important research studies published on this topic in the last 18 months.

RECENT FINDINGS

The implementation of rapid referral systems and use of large vessel imaging have improved the diagnosis of giant cell arteritis. A population-based study in immunoglobulin G4-related disease provides incidence and prevalence estimates for the United States for the first time. Recently published data supported viral infectious triggers for Kawasaki disease and immunoglobulin A vasculitis. Population studies in antineutrophil cytoplasmic antibody associated vasculitis report an increase in the incidence of eosinophilic granulomatosis with polyangiitis and have provided further insights into the burden of cardiovascular disease in these patients. Data on Behçet's disease continues to show increased all-cause mortality and need for better treatment strategies.

SUMMARY

Recent literature highlights the heterogeneity of the epidemiology of vasculitis in different parts of the world as well as associated outcomes, comorbidities, and potential triggers. Thought new classification criteria are being employed in some forms of vasculitis, standardization of case identification remains an unmet need in multiple other forms of vasculitis.

Strawberry gingivitis as an initial presentation of granulomatosis with polyangiitis in an older adult

OBJECTIVE

To describe a rare case of granulomatosis with polyangiitis (GPA) in an older adult in light of the existing literature.

BACKGROUND

GPA is a potentially life-threatening multisystem necrotising vasculitis, characterised by a spectrum of oral mucosal lesions that present diagnostic challenges.

MATERIALS AND METHODS

A 76-year-old female patient presented with asymptomatic granular and haemorrhage swelling ("strawberry" gingivitis) affecting the upper and lower anterior and posterior gingivae. Cytoplasmic antineutrophil cytoplasmic antibody (ANCA) was positive. Concurrent kidney lesions were diagnosed.

RESULTS

Histopathological examination revealed a pseudoepitheliomatous proliferation with perivascular inflammation and a dense eosinophilic infiltrate. After a 5-year follow-up, the patient showed no signs of recurrence. A literature review performed using PubMed, Web of Science and Scopus identified 22 documented cases of GPA-related oral lesions in older adults, with equal sex distribution and 63.6% occurring in the seventh decade of life.

CONCLUSION

Early recognition and diagnosis of "strawberry" gingivitis in older adults with GPA are crucial, as these oral manifestations may be the initial presentation of the disease.

The association between serum lipids at diagnosis and renal outcome in microscopic polyangiitis patients

Objectives

Microscopic polyangiitis (MPA) is a subgroup of ANCA-associated vasculitis (AAV), which is characterized by vascular endothelial cell damage caused by abnormally activated neutrophils. Dyslipidemia is associated with vascular endothelial cell injury, and the relationship between blood lipid levels and renal prognosis in MPA patients is not clear. We aim to investigate the correlation between blood lipid levels at diagnosis and renal prognosis in MPA patients.

Methods

Firstly, we retrospectively included 110 patients diagnosed with MPA and the primary endpoint was the occurrence of end stage renal disease (ESRD). The association between blood lipids at diagnosis and renal outcome was evaluated with Cox regression analysis and survival analysis. Secondly, we explored the potential underlying mechanism of poor renal prognosis in patients with high triglycerides (TG) levels at diagnosis using data independent acquisition (DIA) quantitative proteomics.

Results

During a median follow-up period of 23 months, 44 out of 110 patients (40%) developed ESRD. High serum TG at diagnosis was associated with ESRD development after adjusting for several confounding factors including age, gender, body mass index (BMI), hypertension, diabetes mellitus, estimated glomerular filtration rate (eGFR) and Birmingham Vasculitis Activity Score (BVAS). Serum very low-density lipoprotein (VLDL) demonstrated a marginal trend towards association with ESRD development. MPA patients with TG >1.45 mmol/L or VLDL > 0.66 mmol/L had significantly higher risk of ESRD development than those with TG ≤ 1.45 mmol/L or VLDL ≤ 0.66 mmol/L. DIA quantitative proteomics analysis suggested that patients with elevated TG levels and severe MPA had an upregulation of profibrotic pathways, inflammatory signaling, and complement and coagulation cascades, in contrast to those with lower TG levels and milder disease severity.

Conclusions

In MPA patients, high TG or VLDL at diagnosis is associated with an increased risk of ESRD development. The potential mechanisms may be associated with the upregulation of profibrotic and inflammatory signaling pathways, and the activation of complement and coagulation cascades.

Red flags for clinical suspicion of eosinophilic granulomatosis with polyangiitis (EGPA)

BACKGROUND

Eosinophilic granulomatosis with polyangiitis (EGPA), is a rare ANCA-associated systemic vasculitis. Its overlapping features with other vasculitic or eosinophilic diseases, and the wide and heterogeneous range of clinical manifestations, often result in a delay to diagnosis.

OBJECTIVE

To identify red flags that raise a suspicion of EGPA to prompt diagnostic testing and to present an evidence-based clinical checklist tool for use in routine clinical practice.

METHODS

Systematic literature review and expert consensus to identify a list of red flags based on clinical judgement. GRADE applied to generate a strength of recommendation for each red flag and to develop a checklist tool.

RESULTS

86 studies were included. 40 red flags were identified as relevant to raise a suspicion of EGPA and assessed by the experts as being clinically significant. Experts agreed that a diagnosis of EGPA should be considered in a patient aged ≥6 years with a blood eosinophil level >1000 cells/µL if untreated and >500 cells/µL if previously treated with any medication likely to have altered the blood eosinophil count. The presence of asthma and/or nasal polyposis should reinforce a suspicion of EGPA. Red flags of asthma, lung infiltrates, pericarditis, cardiomyopathy, polyneuropathy, biopsy with inflammatory eosinophilic infiltrates, palpable purpura, digital ischaemia and ANCA positivity, usually anti-myeloperoxidase, among others, were identified.

CONCLUSION

The identification of a comprehensive set of red flags could be used to raise a suspicion of EGPA in patients with eosinophilia, providing clinicians with an evidence-based checklist tool that can be integrated into their practice.

Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis in China: Epidemiology, Management, Prognosis, and Outlook

Background

Increasing evidence indicates that clinicopathologic phenotypes and ANCA serotypes may differ ethnically and geographically. This review highlights the progress in the prevalence, pathogenesis, management, and outcomes of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in China.

Summary

AAV is not rare in China. Cumulative evidence has demonstrated a significant preponderance of microscopic polyangiitis (MPA) and myeloperoxidase (MPO)-ANCA AAV in China. Even in patients with granulomatosis with polyangiitis (GPA), there is a predominance of MPO-ANCA over proteinase 3 (PR3)-ANCA, presenting a unique subset. The pathogenesis of AAV is multifactorial, with the role of complement activation being highlighted during recent years. Treatment strategies for AAV in China have also been refined recently. A rapid tapering of glucocorticoids to minimize exposure has been recommended by the Chinese guidelines. Along with a better understanding of the disease, B cell-targeted therapy and complement-targeted therapy are developing. A considerable number of patients in China received rituximab treatment and achieved remission. However, infection risk and associated mortality still remain concerns. Therefore, less rituximab exposure should be considered and evaluated in Chinese AAV patients. Prognostic factors have been reviewed. Of note, along with improved outcomes, there is an increase of cardiovascular and malignant-related death, warranting specific care. Recently, a modified renal risk score model has been validated for early risk prediction in Chinese AAV patients. Moreover, emerging biomarkers for AAV, including complement components, have been identified in Chinese patients.

Key Messages

There is a preponderance of MPA and MPO-ANCA in China. Treatment strategies for Chinese AAV patients generally align with those in western countries, and to some extent, less aggressive. Prognostic factors and emerging biomarkers for AAV in China have been identified. Further challenges include optimizing interventions, minimizing treatment-related comorbidities, improving disease monitoring, and enhancing life qualities of AAV patients.

Treatment strategies for ANCA-associated vasculitides: from standard protocols to future horizons

INTRODUCTION

ANCA-associated vasculitides (AAV), classified into granulomatosis with polyangiitis, microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis represent a group of disorders characterized by necrotizing vasculitis of small vessels, endothelial injury and tissue damage. The outcomes and prognosis of AAV have undergone significant changes with the introduction of glucocorticoids (GCs) and other immunosuppressants (cyclophosphamide, azathioprine, methotrexate, and mycophenolate mofetil). The enhanced understanding of pathogenesis has subsequently led to the incorporation into clinical practice of drugs targeting specific therapeutic targets.

AREAS COVERED

After an extensive literature search of Pubmed, Medline, Embase of the most recent evidence, we provide an overview of available treatments, highlighting how newer drugs have integrated into standard protocols. Our review also explores potential new therapeutic targets, including B cell depletion and inhibition, T cell inhibition, complement inhibition, and IL-5 and IgE inhibition.

EXPERT OPINION

There is hope that the new treatment targets currently under study in AAV may enable a faster and more lasting clinical response, ensuring the reduction of possible side effects from therapies. Moreover, numerous aspects necessitate further exploration in the future, such as tailoring of GCs, integration of GCs-sparing agents, efficacy of combination therapy, optimal maintenance therapy, to reduce organ-damage and improve quality of life.

ANCA-Positive Small-Vessel Vasculitis Following SARS-CoV-2 Vaccination-A Systematic Review

As vaccinations against the SARS-CoV-2 virus have become a crucial tool in controlling the spread of the disease, reports of rare health complications have emerged, including new-onset antineutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAV). We systematically reviewed new-onset AAV following COVID-19 vaccination case reports and case series published in three databases before January 2024 following PRISMA guidelines to understand the characteristics of possible causal relationships or coincidences. In total, 404 articles were screened respectively by title, abstracts, and full-texts. Thirty-four papers fulfilled the inclusion criteria and have been analyzed, covering 44 patients with new-onset AAV after COVID-19 vaccination with no prior history of COVID-19 infection. Data regarding patients' metrics, comorbidities, vaccination characteristics, symptoms, diagnostics, treatment, and outcomes were investigated and summarized. The cohort consisted predominantly of females. AAV diagnosis was confirmed via biopsy, with renal dysfunction as a prevailing manifestation. In most cases, the first symptoms of AAV developed after the second dose; moreover, Pfizer-BioNTech was the most frequently administered vaccine among the analyzed cohort. Primary treatment involved glucocorticoid therapy, with a mostly favourable response. This systematic review aims to raise awareness among clinicians in the field regarding this rare but possible complication, to promote the prompt recognition and diagnosis of de novo ANCA-positive small-vessel vasculitis in timely association with SARS-CoV-2 vaccination.

Suitability of reduced dose glucocorticoids therapy regimen for antibody-associated vasculitis patients with TB: a retrospective study

INTENTION

Immunosuppressive therapy is the major treatment approach for patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). Due to impaired cellular immunological function and the use of glucocorticoids and immunosuppressants, AAV patients are predisposed to opportunistic infections, including tuberculosis (TB). This retrospective study aims to analyze the clinical characteristics of patients with AAV and TB and explore suitable glucocorticoid regimens for them. So as to provide a basis for future clinical guidelines and have important value for guiding clinical treatment.

METHODS

This study retrospectively reviewed 58 AAV patients (18-80 years old) with TB admitted to Changsha Central Hospital Affiliated with the University of South China from 2016.1 to 2023.4 Patients were divided into standard-dose and reduced-dose glucocorticoid groups before retrospectively analyzing their medical records.

RESULTS

A total of 58 AAV patients with TB were enrolled, with 15 dying throughout the monitoring period. Through analysis data, compared with the standard-dose group, the reduced group had less proteinuria and hematuria. In survival analysis, the reduced-dose glucocorticoid group had lower mortality than the standard-dose group (P = 0.03); however, no significant difference was noted in the use of immunoglobulin (P = 0.39), tuberculosis activity (P = 0.64), and age stratification (P = 0.40). The BVAS score before treatment and 6 months post-treatment suggest that the two regimens cause the same risk of ESKD (P > 0.05).

CONCLUSION

In conclusion, the reduced glucocorticoid dose group can achieve the same curative effect as the standard dose group and has less damage to the kidney in hematuria and proteinuria. Therefore, the reduced glucocorticoid dose treatment regimen may be more suitable for AAV patients with TB.

The HLA region in ANCA-associated vasculitis: characterisation of genetic associations in a Scandinavian patient population

OBJECTIVE

The antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are inflammatory disorders with ANCA autoantibodies recognising either proteinase 3 (PR3-AAV) or myeloperoxidase (MPO-AAV). PR3-AAV and MPO-AAV have been associated with distinct loci in the human leucocyte antigen (HLA) region. While the association between MPO-AAV and HLA has been well characterised in East Asian populations where MPO-AAV is more common, studies in populations of European descent are limited. The aim of this study was to thoroughly characterise associations to the HLA region in Scandinavian patients with PR3-AAV as well as MPO-AAV.

METHODS

Genotypes of single-nucleotide polymorphisms (SNPs) located in the HLA region were extracted from a targeted exome-sequencing dataset comprising Scandinavian AAV cases and controls. Classical HLA alleles were called using xHLA. After quality control, association analyses were performed of a joint SNP/classical HLA allele dataset for cases with PR3-AAV (n=411) and MPO-AAV (n=162) versus controls (n=1595). Disease-associated genetic variants were analysed for association with organ involvement, age at diagnosis and relapse, respectively.

RESULTS

PR3-AAV was significantly associated with both HLA-DPB1*04:01 and rs1042335 at the HLA-DPB1 locus, also after stepwise conditional analysis. MPO-AAV was significantly associated with HLA-DRB1*04:04. Neither carriage of HLA-DPB1*04:01 alleles in PR3-AAV nor of HLA-DRB1*04:04 alleles in MPO-AAV were associated with organ involvement, age at diagnosis or relapse.

CONCLUSIONS

The association to the HLA region was distinct in Scandinavian cases with MPO-AAV compared with cases of East Asian descent. In PR3-AAV, the two separate signals of association to the HLD-DPB1 region mediate potentially different functional effects.

Developing a disease-specific patient reported outcome measure to enhance understanding of the lived experiences of ANCA associated vasculitis: A protocol paper

Anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) is a chronic, relapsing-remitting condition associated with increased morbidity. Previous research has shown patients with AAV report high levels of fatigue, pain, depression and anxiety. Over recent years successful work has been carried out to improve clinical outcomes, resulting in reduced mortality and end stage kidney disease (ESKD). Despite this, little work has been done to better understand the role of the patient within this condition. The prevalence of AAV is increasing and to date, there is a shortage of specific tools that assess and measure key features relating to patient reported outcomes (PROs). This protocol details how we can better understand the lived experiences of those with AAV through the development of a disease specific, patient reported outcome measure (PROM), to be used in clinic practice. This will allow us to recognise and validate PROs and the impact the disease and its treatment has on patients' health related quality of life (HRQoL). In addition, we aim to identify potential differences in PRO's between demographics, organ involvement and treatment subgroups in AAV as well as outcomes relating to the patient experience. Patients from a single centre in the UK will be recruited to take part in the exploratory qualitative study which will include focus groups and semi-structured interviews. The inclusion criteria comprise anyone with a diagnosis of AAV and willing to participate, including those who have active or relapsing disease, those are economically active, unemployed, retired and patients receiving renal replacement therapy. The aim of the project is to identify key issues patients experience in relation to their disease and its management and how these can be better assessed in a new PROM developed for use in the clinic setting. This will enable better delivery of individualised care and inform shared decision making, while also serving as a platform for future research looking at PROs in other glomerulonephritides.

Trends in health care of patients with vasculitides, including giant cell arteritis, Takayasu arteritis, ANCA-associated vasculitis and Behçet's disease: cross-sectional data of the German National Database 2007-2021

The aim of this study is to present the current care situation of patients with giant cell arteritis (GCA), Takayasu arteritis (TAK), ANCA-associated vasculitis (AAV) and Behçet's disease (BD). Trends over the last 15 years will reflect improvements and remaining deficits in the management of vasculitides. Consecutive cross-sectional data from patients with vasculitides from the German National Database (NDB) of the Collaborative Arthritis Centres between 2007 and 2021 were included. Medication, physician- and patient-reported outcomes on disease activity and disease burden, inpatient stays and occupational participation are compared for different vasculitis entities and over time. Employment rates were compared to German population rates. Between 502 and 854 vasculitis patients were annually documented. GCA and AAV were the most common vasculitides. Median disease duration ranged from 2 to 16 years. Over the years, glucocorticoids decreased in proportion and dose, most markedly in GCA and TAK, while biologic therapies increased up to 27%. Physicians rated disease activity as low for the vast majority of patients, while patients-reported moderate outcomes in many dimensions. PROs remained largely unchanged. The proportion of employed patients (< 65 years) increased from 47 to 57%. In recent years, biologics are increasingly used in patients with vasculitides, while glucocorticoids decreased significantly. PRO's have not improved. Work participation increased but remains lower than that in the German population.

Systematic review to estimate the prevalence of inflammatory rheumatic diseases in Germany

OBJECTIVE

This study aimed to update the prevalence estimates of inflammatory rheumatic diseases (IRD) in Germany.

METHODS

A systematic literature search in PubMed and Web of Science (last search 08 November 2022) identified original articles (regional and nationwide surveys and claims data analyses for arthritides, connective tissue diseases, and vasculitides) on prevalences for the period 2014-2022. Data sources, collection period, case definition, and risk of bias are reported. Prevalences were estimated from available national data, with consideration of international data.

RESULTS

Screening by two authors yielded 263 hits, of which 18 claims data analyses and 2 surveys met the inclusion criteria. Prevalences ranged from 0.42 to 1.85% (rheumatoid arthritis), 0.32-0.5% (ankylosing spondylitis), 0.11-0.32% (psoriatic arthritis), 0.037-0.14% (systemic lupus erythematosus), 0.07-0.77% (Sjögren's disease/sicca syndrome), 0.14-0.15% (polymyalgia rheumatica, ≥ 40 years), 0.04-0.05% (giant cell arteritis, ≥ 50 years), and 0.015-0.026% (ANCA-associated vasculitis). The risk of bias was moderate in 13 and high in 7 studies. Based on the results, we estimate the prevalence of IRD in Germany to be 2.2-3.0%, which corresponds to approximately 1.5-2.1 million affected individuals. The prevalence of juvenile idiopathic arthritis was reported to be around 0.10% (0.07-0.10%) of 0-18-year-olds, corresponding to about 14,000 children and adolescents in Germany.

CONCLUSION

This systematic review shows an increase in the prevalence of IRD in Germany, which is almost exclusively based on claims data analyses. In the absence of multistage population studies, the available data are, overall, uncertain sources for prevalence estimates, with a moderate to high risk of bias.

Disease Activity and Tendency to Relapse in ANCA-Associated Vasculitis Are Reflected in Neutrophil and Intermediate Monocyte Frequencies

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of autoimmune diseases with inflammation affecting small blood vessels and includes granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA). In this study, we investigated granulocyte and monocyte subsets in a large cohort of AAV patients with emphasis on disease activity and tendency to relapse. A cohort of 105 patients with GPA or MPA and 126 healthy controls (HCs) were included. Clinical and laboratory data were collected for all patients, including disease activity, tendency to relapse, and pharmacological treatment. Using flow cytometry, circulating eosinophils, basophils, neutrophils, and monocytes were assessed. The monocytes were subdivided into classical (CD14++CD16-), intermediate (CD14++CD16+), and nonclassical (CD14-CD16+) monocytes. Mature (CD16high) or newly released (CD16dim) neutrophils were defined, as well as the frequency of CD177+ neutrophils. AAV patients displayed increased frequencies of intermediate monocytes, mature and newly released neutrophils, and an expanded population of CD177+ neutrophils compared to HC. MPA patients differed from GPA patients in terms of lower frequency of classical monocytes. No differences in cell frequencies regarding ANCA phenotype were observed. Paired data from 23 patients demonstrated that active disease was associated with an increased frequency of mature neutrophils and a decreased frequency of monocytes, in particular intermediate monocytes. Moreover, GPA patients with a tendency to relapse displayed an increased frequency of mature neutrophils with increased expression of CD177+. Relapsing MPA patients, on the other hand, showed decreased frequency of intermediate monocytes. Finally, rituximab treatment was associated with increased frequencies of classical and intermediate monocytes. In conclusion, AAV patients exhibit a skewing of different neutrophil and monocyte subpopulations that are associated with disease subtypes, disease activity, rituximab treatment, and propensity to relapse. These changes may contribute to the inflammatory process and could potentially be used as biomarkers for relapse prediction.

Epidemiology of systemic vasculitis

PURPOSE OF REVIEW

Epidemiology of vasculitides exhibit geographic variation and data from some parts of the world are still scarce. Increased recognition of these rare diseases and improvement in diagnosis and patient care may lead to changes in their epidemiology. In this review, we aimed to highlight the most recent work on the epidemiology of systemic vasculitis.

RECENT FINDINGS

New data from countries where information on the epidemiology of giant cell arteritis, Takayasu arteritis and Behçet syndrome were limited have revealed that these conditions are not as rare as previously believed. The incidence rates during the coronavirus disease 2019 pandemic highlight the link between Kawasaki disease and respiratory pathogens. The use of different classification criteria hampers the comparison of true incidence and prevalence rates in antineutophil cytoplasmic antibody (ANCA)-associated vasculitis and its subtypes between geographies and over time.

SUMMARY

Recent studies have highlighted the epidemiology of vasculitides in different parts of the world and changing trends. Standardization of study design and disease definitions is needed to improve the reliability and comparability of the results.

A unique case of indolent microscopic polyangiitis in an elderly gentleman: a case report and brief review

Antineutrophil cytoplasmic autoantibody associated vasculitides has 3 different types: Granulomatosis with polyangiitis, eosinophilic granulomatosis and polyangiitis and microscopic polyangiitis. These vasculitides manifest differently based on which area of small and medium size vessels in our bodies that it affects. In this case report, we discuss a unique case of microscopic polyangiitis diagnosed in a 75-year-old male who was relatively asymptomatic i.e. indolent, apart from nodules present in the lung with the use of the diagnostic criteria outlined by 2022 American College of Rheumatology and European Alliance of Associations for Rheumatology. In addition, we reviewed briefly about vasculitis, its epidemiology and the workup of microscopic polyangiitis.

The Role of Neutrophils in ANCA-Associated Vasculitis: The Pathogenic Role and Diagnostic Utility of Autoantibodies

Recent years have brought progress in understanding the role of the neutrophil, dispelling the dogma of homogeneous cells mainly involved in the prime defence against pathogens, shedding light on their pathogenic role in inflammatory diseases and on the importance of antineutrophil-cytoplasmic antibodies' pathogenic role in ANCA-associated vasculitides vasculitis (AAV). Myeloperoxidase (MPO) and proteinase 3 (PR3) expressed in neutrophil granulocytes are the most common targets for ANCAs and contribute to the formation of MPO-ANCAs and PR3-ANCAs which, released to the bloodstream, become an excellent diagnostic tool for AAV. In this study, we focus on increasing the clinical and experimental evidence that supports the pathogenic role of ANCAs in AAV. Additionally, we discuss the diagnostic utility of ANCAs for disease activity and prognosis in AAV. Understanding the central role of ANCAs in AAV is crucial for advancing our knowledge of these complex disorders and developing targeted therapeutic strategies in the era of personalized medicine.

The Association Between Age at Diagnosis and Disease Characteristics and Damage in Patients With ANCA-Associated Vasculitis

OBJECTIVE

This study examined the relationship between age at diagnosis and disease characteristics and damage in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

Analysis of a prospective longitudinal cohort of patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic GPA (EGPA) in the Vasculitis Clinical Research Consortium (2013-2021). Disease cohorts were divided by age at diagnosis (years): children (<18), young adults (18-40), middle-aged adults (41-65), and older adults (>65). Data included demographics, ANCA type, clinical characteristics, Vasculitis Damage Index (VDI) scores, ANCA Vasculitis Index of Damage (AVID) scores, and novel disease-specific and non-disease-specific damage scores built from VDI and AVID items.

RESULTS

Analysis included data from 1020 patients with GPA/MPA and 357 with EGPA. Female predominance in GPA/MPA decreased with age at diagnosis. AAV in childhood was more often GPA and proteinase 3-ANCA positive. Children with GPA/MPA experienced more subglottic stenosis and alveolar hemorrhage; children and young adults with EGPA experienced more alveolar hemorrhage, need for intubation, and gastrointestinal involvement. Older adults (GPA/MPA) had more neurologic manifestations. After adjusting for disease duration, medications, tobacco, and ANCA, all damage scores increased with age at diagnosis for GPA/MPA (P < 0.001) except the disease-specific damage score, which did not differ (P = 0.44). For EGPA, VDI scores increased with age at diagnosis (P < 0.009), whereas all other scores were not significantly different.

CONCLUSION

Age at diagnosis is associated with clinical characteristics in AAV. Although VDI and AVID scores increase with age at diagnosis, this is driven by non-disease-specific damage items.

[Systematic review to estimate the prevalence of inflammatory rheumatic diseases in Germany. German version]

OBJECTIVE

To update the estimated prevalence of inflammatory rheumatic diseases (IRD) in Germany.

METHODS

A systematic literature search in PubMed and Web of Science (last search 8 November 2022) identified original articles (regional and nationwide surveys and routine data analyses for arthritides, connective tissue diseases, and vasculitides) on the prevalence for the period 2014-2022. Data sources, collection period, case definition, and risk of bias are reported. The prevalences were estimated from available national data, with consideration of international data.

RESULTS

Screening by 2 authors yielded 263 hits, of which 18 routine data analyses and 2 surveys met the inclusion criteria. Prevalence data ranged from 0.42% to 1.85% (rheumatoid arthritis), 0.32-0.5% (ankylosing spondylitis), 0.11-0.32% (psoriatic arthritis), 0.037-0.14% (systemic lupus erythematosus), 0.07-0.77% (Sjoegren's disease/sicca syndrome), 0.14-0.15% (polymyalgia rheumatica, ≥ 40 years), 0.04-0.05% (giant cell arteritis, ≥ 50 years), and 0.015-0.026% (ANCA-associated vasculitis). The risk of bias was moderate in 13 and high in 7 studies. Based on the results, we estimate the prevalence of IRD in Germany to be 2.2-3.0%, which corresponds to approximately 1.5-2.1 million affected individuals. Prevalence data of juvenile idiopathic arthritis was reported to be around 0.10% (0.07-0.10%) of patients 0-18 years old, corresponding to about 14,000 children and adolescents in Germany.

CONCLUSION

This systematic review shows an increase in the prevalence of IRD in Germany, which is almost exclusively based on routine data analyses. In the absence of multistage population studies, the available data are overall uncertain sources for prevalence estimates at moderate to high risk of bias.

Significance of early treatment in granulomatosis with polyangiitis vasculitis

Vasculitis is a multisystemic disease that affects vessels of different sizes. Its presentation can vary widely depending on the system involved. It may present with constitutional symptoms or with specific features of end-organ involvement. The diagnosis is built on a compatible pattern of clinical features supported by specific serological or radiological investigations and confirmatory biopsy. Tissue biopsy is vital to confirm the diagnosis of vasculitis; however, this should not delay treatment when presentation strongly suggests vasculitis. We describe a case of a 72-year-old man treated with steroids, plasma exchange, and rituximab for suspected granulomatosis with polyangiitis (GPA) given his clinical presentation including suspected scleritis of the right eye, hearing changes, sinusitis, diffuse alveolar hemorrhage, pulmonary lesions, kidney failure, palpable purpura, and radiological evidence of pansinusitis and pulmonary lesions without waiting for serology or tissue confirmation. This case highlights the importance of recognizing the clinical features of GPA to initiate prompt treatment as it can progress rapidly and be fatal.

Sex Differences in Clinical Manifestations of Hospitalized Patients With Eosinophilic Granulomatosis With Polyangiitis: A Retrospective Cohort Study

OBJECTIVE

To investigate the effect of sex on the clinical characteristics, prognoses, and therapeutic selection of eosinophilic granulomatosis with polyangiitis (EGPA).

METHODS

We retrospectively enrolled 170 hospitalized patients with EGPA who were managed at our hospital between 2007 and 2020. Detailed clinical data were reviewed. Manifestations, prognoses, treatments, and outcomes were compared between female and male patients. Cumulative survival rates were calculated using Kaplan-Meier curves.

RESULTS

In this cohort, the male to female ratio was 1.4:1. Renal involvement was more frequent in male patients, including serum creatinine elevation, and proteinuria > 1 g/24 h. Severe gastrointestinal (GI) involvement occurred more commonly in male patients. Female patients had longer allergy duration and higher ratios of allergic rhinitis and asthma. Sex differences in proteinuria > 1 g/24 h, serum creatinine > 150 mmol/L, severe GI involvement, and weight loss were more significant in patients aged ≤ 55 years than those in patients aged > 55 years. Overall, male patients had a higher Birmingham Vasculitis Activity Score and a worse prognosis assessed at diagnosis, with a lower proportion of 1996 Five Factor Score = 0 than females. Regarding treatment selection, methylprednisolone pulse and cyclophosphamide were administered more frequently to male patients. All-cause mortality and cumulative survival rates were comparable between the sexes.

CONCLUSION

In this Chinese EGPA cohort, male and female patients showed distinct disease phenotypes. Male patients with EGPA had a higher disease activity at diagnosis and required more aggressive treatment for remission induction.

Churg-Strauss syndrome-associated heart failure and left ventricular thrombosis

We present a case of a 47-year-old woman with a history of asthma and mononeuritis who presented with shortness of breath and fatigue. Heart failure was diagnosed and echocardiography revealed large floating thrombi attached to the left ventricular walls. Cardiac magnetic resonance imaging showed evidence of myocarditis and angiitis. Blood count revealed eosinophilia. She was diagnosed with eosinophilic granulomatosis with polyangiitis or Churg-Strauss syndrome (CSS) according to recently updated criteria. Medical management with specific aetiology (anticoagulation or immunosuppression) and heart failure treatment resulted in clinical improvement. We further discuss the diagnostic approach of CSS with cardiovascular complications and therapeutic management.

[Eosinophilia: hypereosinophilic syndrome vs. eosinophilic granulomatosis with polyangiitis]

Hypereosinophilic syndrome (HES) is defined as a peripheral eosinophil count of > 1500/μl (assessed twice at an interval of ≥ 2 weeks) and an eosinophil-induced organ damage. Idiopathic HES is differentiated from primary (clonal or neoplastic) HES and secondary (reactive) HES, depending on the etiology. Eosinophilic granulomatosis with polyangiitis (EGPA) is categorized as a secondary form of HES and is characterized by hypereosinophilia and vasculitis of small to medium-sized vessels and can be associated with an antineutrophil cytoplasmic antibody (ANCA). The treatment of HES is dependent on the etiology. Clonal HES is treated according to the respective genetic aberration, e.g. with tyrosine kinase inhibitors or chemotherapy and allogenic stem cell transplantation. Secondary forms should be treated according to the underlying cause (e.g. parasitic infection). The treatment of EGPA is carried out with immunosuppressants depending on the disease stage and disease activity. Conventional drugs, such as glucocorticoids (GC), cyclophosphamide (CYC) and methotrexate (MTX) or biologics, such as the monoclonal anti-IL5 antibody mepolizumab are commonly used. Mepolizumab is also a good option for the treatment of idiopathic HES.

Kidney diseases

Dysregulation and accelerated activation of the alternative pathway (AP) of complement is known to cause or accentuate several pathologic conditions in which kidney injury leads to the appearance of hematuria and proteinuria and ultimately to the development of chronic renal failure. Multiple genetic and acquired defects involving plasma- and membrane-associated proteins are probably necessary to impair the protection of host tissues and to confer a significant predisposition to AP-mediated kidney diseases. This review aims to explore how our current understanding will make it possible to identify the mechanisms that underlie AP-mediated kidney diseases and to discuss the available clinical evidence that supports complement-directed therapies. Although the value of limiting uncontrolled complement activation has long been recognized, incorporating complement-targeted treatments into clinical use has proved challenging. Availability of anti-complement therapy has dramatically transformed the outcome of atypical hemolytic uremic syndrome, one of the most severe kidney diseases. Innovative drugs that directly counteract AP dysregulation have also opened new perspectives for the management of other kidney diseases in which complement activation is involved. However, gained experience indicates that the choice of drug should be tailored to each patient's characteristics, including clinical, histologic, genetic, and biochemical parameters. Successfully treating patients requires further research in the field and close collaboration between clinicians and researchers who have special expertise in the complement system.

Epidemiology of granulomatosis with polyangiitis and microscopic polyangiitis in adults in France

BACKGROUND

Granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) are rare systemic necrotizing vasculitis. The national incidence and prevalence of GPA/MPA and patient mortality remain unknown in France. A real-life study using retrospective data from the French National Health Data System was set up to describe the epidemiology and demographic characteristics of hospitalized GPA and MPA patients, overall and by disease.

METHODS

All adult patients (≥18 years of age) hospitalized for GPA (ICD-10 M31.3) or MPA (ICD-10 M31.7) between 01 and 01-2010 and 31-12-2017 and affiliated to the General health insurance Scheme (covering 76% of the French population) were included in this national retrospective observational study. Descriptive analyses, univariate and multivariable logistic models, Kaplan-Meier survival analysis, and Cox models were performed.

RESULTS

The study involved 4445 prevalent GPA patients (including 1578 incident patients) and 1833 prevalent MPA patients (878 incident patients). Distinction between GPA and MPA diagnosis could not be made for 303 patients (149 incident patients). In people aged over 20 years, the age-standardized incidence rates of GPA and MPA were 0.5 and 0.3/100,000 person-years, respectively and the age-standardized prevalence rates were 10 and 4/100,000 person-years, respectively. The standardized mortality ratios in GPA and MPA patients aged over 20 years were 2.0 and 2.7, respectively, and remained constant. Renal failure, pulmonary and urinary tract infections, as well as coronary disease were more frequent among MPA than GPA patients. One-year survival rates among GPA and MPA patients were 96% (95%CI 94%-97%) and 94% (92%-95%), respectively. Five-year survival rates among GPA and MPA patients were 81% (95% CI 79%-83%) and 72% (68%-75%), respectively. After adjusting for comorbidities, the risk of death was still higher in MPA (hazard ratio 1.26 [95%CI 1.06-1.50]) than in GPA patients.

CONCLUSIONS

Despite advances in the therapeutic management of patients, mortality rates are still high and stable over time, highlighting the need for improved management.

Systematic evaluation of imaging techniques and baseline characteristics in patients with suspected vasculitis

PURPOSE

To assess the diagnostic value of different imaging modalities in distinguishing systemic vasculitis from other internal and immunological diseases.

METHODS

This retrospective study included 134 patients with suspected vasculitis who underwent ultrasound, magnetic resonance imaging (MRI), or 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) between 01/2010 and 01/2019, finally consisting of 70 individuals with vasculitis. The main study parameter was the confirmation of the diagnosis using one of the three different imaging modalities, with the adjudicated clinical and histopathological diagnosis as the gold standard. A secondary parameter was the morphological appearance of the vessel affected by vasculitis.

RESULTS

Patients with systemic vasculitis had myriad clinical manifestations with joint pain as the most common symptom. We found significant correlations between different imaging findings suggestive of vasculitis and the final adjudicated clinical diagnosis. In this context, on MRI, vessel wall thickening, edema, and diameter differed significantly between vasculitis and non-vasculitis groups (p < 0.05). Ultrasound revealed different findings that may serve as red flags in identifying patients with vasculitis, such as vascular occlusion or halo sign (p = 0.02 vs. non-vasculitis group). Interestingly, comparing maximal standardized uptake values from PET/CT examinations with vessel wall thickening or vessel diameter did not result in significant differences (p > 0.05).

CONCLUSIONS

We observed significant correlations between different imaging findings suggestive of vasculitis on ultrasound or MRI and the final adjudicated diagnosis. While ultrasound and MRI were considered suitable imaging methods for detecting and discriminating typical vascular changes, 18F-FDG PET/CT requires careful timing and patient selection given its moderate diagnostic accuracy.