ANCA Associated Vasculitis Subtypes: Recent Insights and Future Perspectives

C5a/C5aR regulates Th1/Th2 imbalance in sepsis-associated lung injury by promoting neutrophil activation to increase PAD4 expression

OBJECTIVE

Multi-organ failure frequently complicates sepsis, with lungs being the primary target. T helper (Th) cell activation and phenotypic imbalance among them contribute significantly to sepsis-associated lung injury. Additionally, the complement system could regulate the polarized phenotype of T lymphocytes. Therefore, this study investigated the effect of C5a/C5a receptor (C5aR)/Peptidylarginine deiminase 4 (PAD4) on the Th1/Th2 ratio in sepsis-induced lung injury.

METHODS

ELISA was used to detect the expression of PAD4, HBP, MPO, IL-1β, IL-10, IL-6, IL-4, syndecan-1, endocan and H3Cit. An LPS-induced septic lung injury mouse model was constructed, with HE and PAS stains evaluating lung damage. BCA kit quantified BALF total protein, Western blot examined C5aR, syndecan-1, endocan, PAD4 levels, while TUNEL and flow cytometry assessed tissue cellular apoptosis. Furthermore, flow cytometry was used to detect the +Th1 and Th2 cells proportion in peripheral blood, and CCK-8 was used to detect BEAS-2B activity.

RESULTS

The results indicated that PAD4 and inflammatory factors were increased in lesion samples compared with controls. In sepsis-induced lung injury mice, addition of GSK484, a PAD4 inhibitor, effectively alleviated sepsis-induced lung edema and inflammatory responses. GSK484 was found to inhibit C5a/C5aR expression and suppress apoptosis and lung injury. Furthermore, GSK484 markedly inhibited Th1 cell phenotypes in vitro. Additionally, GSK484 intervention on Th1 cell phenotype further affected lung epithelial cell injury.

CONCLUSION

In summary, we revealed the mechanism of C5a/C5aR-induced PAD4 upregulation via neutrophil activation in sepsis-associated lung injury, causing a Th1/Th2 imbalance and lung injury, providing a novel approach for sepsis-associated lung injuries treatment.

Inflammatory disorders that affect the cerebral small vessels

ABSTRACT

This comprehensive review synthesizes the latest advancements in understanding inflammatory disorders affecting cerebral small vessels, a distinct yet understudied category within cerebral small vessel diseases (SVD). Unlike classical SVD, these inflammatory conditions exhibit unique clinical presentations, imaging patterns, and pathophysiological mechanisms, posing significant diagnostic and therapeutic challenges. Highlighting their heterogeneity, this review spans primary angiitis of the central nervous system, cerebral amyloid angiopathy-related inflammation, systemic vasculitis, secondary vasculitis, and vasculitis in autoinflammatory diseases. Key discussions focus on emerging insights into immune-mediated processes, neuroimaging characteristics, and histopathological distinctions. Furthermore, this review underscores the importance of standardized diagnostic frameworks, individualized immunomodulation approaches, and novel targeted therapies to address unmet clinical demands.

Association of C4d with disease activity in anti-neutrophil cytoplasmic antibody-associated vasculitis: evidence for classical/lectin complement pathway activation

BACKGROUND

We aimed to investigate the involvement of the classical/lectin complement pathway in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) by exploring the complement activation fragment C4d in association to AAV activity.

METHODS

Forty patients with active AAV and twenty population-based controls were included. The study included 27 (67.5%) patients with a diagnosis of GPA and 13 (32.5%) with MPA. Twenty-four patients (60%) were anti-proteinase 3 (PR3)-ANCA positive and 16 (40%) anti-myeloperoxidase (MPO)-ANCA positive. Thirty-three (82.5%) patients had kidney involvement. A follow-up sample obtained after induction therapy (median 6 months) was available for 24 of the patients, of whom 20 were in remission. Plasma C4d was analysed by ELISA detecting an epitope that arises upon complement-mediated cleavage. Plasma complement factor 4 (C4) and the soluble terminal complement complex (sTCC) were analysed by ELISA. The C4d/C4 ratio was calculated. HLA-DRB1-typing and immunohistochemistry for C4d in kidney biopsies were performed.

RESULTS

Patients with active AAV had higher C4d, sTCC levels and C4d/C4 ratio than controls (p < 0.001, p = 0.004, p < 0.001). C4d, sTCC levels and C4d/C4 ratio all decreased from active disease to remission (p = 0.010, p = 0.009, p = 0.011). C4d levels in AAV patients in remission remained higher than population-based controls (p = 0.026). Active anti-PR3-ANCA patients had higher C4d levels and C4d/C4 ratio than anti-MPO-ANCA patients (p = 0.001, p = 0.007). Patients with active AAV and kidney involvement had lower C4d levels than patients without (p = 0.04). C4d levels and C4d/C4 ratio correlated positively with the percentage of normal glomeruli in kidney biopsies. The immunohistochemistry was negative for C4d in kidney biopsies.

CONCLUSIONS

The specific C4d assay revealed activity in the classical/lectin complement pathway in AAV, which reflected general disease activity, but was not associated specifically with kidney involvement. C4d levels differed depending on anti-PR3/MPO-ANCA subtypes suggesting differences in complement activation and underlying pathogenetic mechanisms. The findings imply that the classical/lectin complement pathway may play a more significant role in AAV pathogenesis than previously reported and that plasma C4d levels and C4d/C4 ratio may be biomarker candidates for disease activity and treatment outcome monitoring.

Minimally Invasive Surgical Approach in Granulomatosis with Polyangiitis Complicated with Intramural Descending Aorta Hematoma Followed by Aortic Wall Rupture

Background and Clinical Significance: Granulomatosis with polyangiitis (GPA) represents a rare autoimmune disease with granulomatous inflammation, tissue necrosis, and systemic vasculitis of the small and medium blood vessels. Although the clinical elements vary, aortic involvement is exceptional and it represents a challenge that requires a rapid intervention with the potential of displaying a fulminant evolution. Case Presentation: We report a 64-year-old male with an 18-year history of GPA who presented atypical low back pain. Following ultrasound and computed tomography exams, the initial suspicion was an intramural descending aorta hematoma, surrounded by a peri-aortic sleeve suggesting a chronic inflammation. Serial non-invasive assessments revealed a progressive lesion within the next 10 to 12 days to an aortic wall rupture, despite the absence of previous aneurysmal changes. The peri-aortic fibrous inflammatory sleeve was life-saving, and emergency minimally invasive surgery was successful, including the massive improvement in back pain. Conclusions: To our knowledge, this is a very rare scenario in GPA; we found only 18 other cases (the oldest report being from 1994). An interventional approach was mentioned in a few cases as seen in this instance. Glucocorticoid medication for GPA might act as a potential contributor to symptomatic osteoporotic fractures which require a prompt differential diagnosis. Unusual aortic manifestations (such as intramural aortic hematoma or aortic wall rupture) are difficult to recognize since the index of clinical suspicion is rather low. A prompt intervention may be life-saving and a multidisciplinary team is mandatory. Minimally invasive surgical correction of the aortic event represents an optimum management in the modern era. Such cases add to the limited data we have so far with respect to unusual outcomes in long-standing GPAs.

Relationships between patient and physician global assessments in anti-neutrophil cytoplasmic antibody-associated vasculitis

INTRODUCTION/OBJECTIVES

Patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) experience reduced health-related quality of life (HRQoL). Global assessment tools use visual analogue scales to provide patients' and physicians' views on disease activity or the patient's overall health and well-being. The aim of this study was to examine the relationships between patient and physician global assessments (PtGA and PhGa) as they relate to overall health in people with AAV.

METHODS

Patients with AAV attending a tertiary vasculitis clinic participated in this prospective observational study. The primary outcome measured was PtGA and PhGA scores, with higher scores representing better health. SF-36 assessed HRQoL. Discordant scores were defined as an absolute difference of ≥ 20 between PhGA and PtGA.

RESULTS

Ninety-seven patients (mean age 58 years, 46% male) participated. Most were taking immunosuppressive therapy (88%) and had kidney involvement (79%). The mean PhGa and PtGA were similar (mean difference - 2.6, [CI] 0.5, 4.7). Physicians' global assessments were lower in the 43 (44%) patients with active disease, with a trend towards a lower PtGA in this group. Patients' global assessments were ≥ 20 points higher than PhGAs in 16 patients and ≥ 20 points lower in 10 patients. Negatively discordant patients (PtGA < PhGA) were older and less likely to have active disease than positively discordant patients.

CONCLUSIONS

Physicians did not systematically overestimate patients' global health when using the global assessment tool. Discordance rates were 26%, within which, physicians were more likely to assess the patient's health lower than patients themselves. Key Points • There remains an unmet need for patient-reported outcomes assessing quality of life in AAV and other diseases. • The global assessment tool correlates with SF-36 which is commonly used as a tool for assessing quality of life. • Physicians do not tend to overestimate patient's global health both overall and within the discordant sub-group. • Assessing PtGA/PhGA discordance could identify unmet priorities for patients and improve shared physician-patient decision-making.

Occurrence and role of Tph cells in various renal diseases

A new population of peripheral helper T (Tph) cells has been identified and contributed to various autoimmune diseases. Tph cells can secrete interleukin-21 (IL-21), interferon (IFN) and C-X-C motif chemokine ligand 13 (CXCL13) to moderate renal disease. Moreover, Tph cells can congregate in huge numbers and immerse within inflamed tissue. Compared to Tfh cells, Tph cells express high programmed cell death protein 1 (PD-1), major histocompatibility complex II (MHC-II), C-C chemokine receptor 2 (CCR2) and C-C chemokine receptor 5 (CCR5) but often lack expression of the chemokine receptor C-X-C chemokine receptor 5 (CXCR5). They display features distinct from other T cells, which are uniquely poised to promote responses and antibody production of B cells within pathologically inflamed non-lymphoid tissues and a key feature of Tph cells. In this review, we summarize recent findings on the role of Tph cells in chronic kidney disease, acute kidney injury, kidney transplantation and various renal diseases.

Diagnostic and prognostic role of serum interleukin-6 and carotid ultrasonography to detect subclinical atherosclerosis in patients with RA and ANCA-associated vasculitis

ANCA-associated vasculitis (AAV) can affect multiple organs with severe life-threatening manifestations. Disease monitoring is difficult due to a lack of defined biomarkers. We aimed to assess the diagnostic role of serum interleukin-6 and vascular ultrasonography in AAV and subclinical atherosclerosis. The study included 20 AAV patients and two control groups of 34 patients with rheumatoid arthritis (RA) and 35 healthy controls. The levels of Il-6, carotid intima-media thickness test (CIMT), atherosclerotic plaque, and degree of stenosis were investigated. A GRACE-risk score was calculated for AAV and RA patients. The AAV patients had elevated levels of IL-6 (115 ± 23.96) compared to the RA patients (91.25 ± 42.63) and the healthy controls (15.65 ± 3.30), p < 0.001. IL-6 showed a diagnostic accuracy of 73% in distinguishing AAV from RA patients (AUC = 0.730; 95% CI 0.591 to 0834). In the AAV group, CIMT was 1.09, above the upper reference value of 0.90, p < 0.001. The AAV patients had a higher median GRACE risk score, and 60% of them had a high risk of cardiovascular events as compared to 35% of the RA patients. Sonography of extracranial vessels and serum levels of IL-6 can be used in daily clinical practice to diagnose and monitor patients with AAV.

Performance of the 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology Classification Criteria for antineutrophil cytoplasmic antibody-associated vasculitis in previously diagnosed adult patients from Türkiye

Objectives: This study aimed to evaluate the applicability of the new 2022 American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) criteria in Turkish adult patients previously diagnosed with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). Patients and methods: One hundred sixty-four patients (96 males, 68 females; mean age: 49.6±14.4 years; range, 18 to 87 years) diagnosed with AAV by experienced rheumatologists between July 2016 and May 2022 were included in this retrospective cross-sectional study and reclassified based on the 1990 ACR criteria, the European Medicines Agency (EMEA) algorithm, and the 2022 ACR/EULAR criteria. For external validation, 83 patients (48 males, 35 females; mean age: 47.3±17.5 years; range, 19 to 81 years) diagnosed with immunoglobulin (Ig)A vasculitis were included. Results: One hundred twenty-six (76.8%) patients had granulomatosis with polyangiitis (GPA), 13 (7.9%) patients had eosinophilic granulomatosis with polyangiitis (EGPA), and 25 (15.2%) patients had microscopic polyangiitis (MPA). According to the criteria, the number of unclassified patients was nine (5.5%) for both the 2022 ACR/EULAR AAV classification criteria and the EMEA algorithm. The new criteria had an almost perfect agreement with the clinician's diagnosis (Cohen's kappa coefficient [κ]=0.858 for GPA, κ=0.820 for EGPA, and κ=0.847 for MPA). The kappa statistics for agreement of 2022 ACR/EULAR classification criteria with the EMEA algorithm were found 0.794 for GPA, 0.820 for EGPA, and 0.700 for MPA. None of the 83 patients diagnosed with IgA vasculitis could be classified as GPA, EGPA, or MPA using the new ACR/EULAR AAV classification criteria. Conclusion: The 2022 ACR/EULAR classification criteria for AAV showed substantial or perfect agreement with the clinical diagnosis and the EMEA algorithm.

Peripheral helper T cells in human diseases

Peripheral helper T cells (Tph) are a specialized subset of CD4+ T cells with the ability to help B cells and induce antibody production. Although usually located in ectopic lymphoid-like structures (ELS), inside the peripheral blood, Tph cells can also be identified. The aberrant proliferation and functions of Tph cells are commonly found in the patients with disease. In this review, first we will summarize the biological characteristics of Tph cells, such as the expression of surface molecules, transcription factors and cytokines, and discuss its B cell help functions. Tph cells also have roles in a wide range of human diseases, including autoimmune diseases, infectious diseases, malignancies etc. Therefore, there is a strong interest in targeting Tph cells to improve treat strategies of human diseases.

New Biomarkers for Systemic Necrotizing Vasculitides

Systemic necrotising vasculitides (SNVs) pose significant challenges due to their diverse clinical manifestations and variable outcomes. Therefore, identifying reliable biomarkers holds promise for improving precision medicine in SNVs. This review explores emerging biomarkers aiming to enhance diagnostic accuracy, prognostic assessment, and disease monitoring. We discuss recent advances in immunological biomarkers, inflammatory indicators, and other parameters that exhibit potential diagnostic and prognostic utility. A comprehensive understanding of these biomarkers may facilitate earlier and more accurate SNV detection, aiding in timely intervention and personalized treatment strategies. Furthermore, we highlight the evolving landscape of disease monitoring through innovative biomarkers, shedding light on their dynamic roles in reflecting disease activity and treatment response. Integrating these novel biomarkers into clinical practice can revolutionize the management of SNVs, ultimately improving patient outcomes and quality of life.

Kidney Biopsy and Immuno-Rheumatological Diseases: A Retrospective and Observational Study

Renal involvement is a common occurrence in patients with immuno-rheumatological diseases (IRDs). Several instances of glomerulonephritis (GN) occur in the setting of IRD and complicate the clinical course of an underlying condition. The aim of this study was to observe the spectrum of nephropathies according to age, kidney function, history of IRD at the time of biopsy, and histopathological kidney diagnosis. We evaluated data relating to 699 consecutive kidney native biopsies (female 52.1%) with a median age of 48 years (IQR 34-62) performed in adult patients collected over 15 years. The study population was divided into three groups: patients with kidney histological findings correlated to underlying IRD (Group 1), patients with kidney histological findings not correlated to underlying IRD (Group 2), and patients with kidney histological findings compatible with "de novo" IRD (absent in personal medical history) (Group 3). Kidney involvement related to IRD was found in 25.2% of patients. Group 1 was mostly represented by lupus nephritis (76.6%), with a younger age than Group 3 (p < 0.001) and by a higher percentage of females than other groups (p < 0.001). Group 3 was the most represented by microscopic polyangiitis (50.8%) when compared with the other two groups (p < 0.001). Acute nephritic syndrome (p < 0.001), acute kidney injury (AKI), and abnormal urinalysis (p < 0.001) were more represented in Group 3 than the other groups. In conclusion, IRDs are characterized by different clinical presentations and heterogeneous histological findings. Kidney biopsy remains fundamental to achieving the correct diagnosis and starting targeted therapy.

How is the patient perspective captured in ANCA-associated vasculitis research? An integrative review

Objective

The aim was to describe how the patient perspective is captured in clinical research on ANCA-associated vasculitis (AAV).

Methods

This integrative review included 2149 publications found in four different databases and manual searches. After screening, 156 articles remained. All articles were sorted and categorized, and 77 original articles were analysed further.

Results

The patient perspective was captured with patient-reported outcome measures (PROMs), single-item questionnaires, project-specific questionnaires and interviews. The most common aspects measured were health-related quality of life, anxiety and depression, and fatigue, and the least common were lifestyle habits, relationships and self-management.

Conclusion

The patient perspective was captured predominantly with generic PROMs and occasionally with a qualitative approach. AVV is a lifelong disease, and the results from this review show that not all aspects of importance to patients are covered with the PROMs used in research. Future studies should include the areas that are the most important for patients.

Changing Phenotypes and Clinical Outcomes Over Time in Microscopic Polyangiitis

Introduction

Diagnosis and management of microscopic polyangiitis (MPA) have evolved considerably over the past decades, but it is unknown whether clinical and histological presentation and patient and renal outcomes have changed accordingly.

Methods

We compared clinical and histopathological characteristic at diagnosis, risk of death, end-stage kidney disease (ESKD), and relapse rate in patients diagnosed with MPA between 1980 and 2022, after grouping them in 2 periods (p): p1980-2001 and p2002-2022. We compared the mortality rate between the 2 periods using Kaplan-Meier estimator and Cox-regression, and competing risks of ESKD and death using the Aalen-Johansen estimator, Fine-Gray multiple regression, and multistate models.

Results

Out of 187 patients, 77 were in p1980-2001 and 110 in p2002 to 2022. Patients in p2002 to 2022 were older (66.2 ± 14.0 SD vs. 57.7 ± 15.8; P < 0.001), had a better kidney function (estimated glomerular filtration rate [eGFR] 25.9 ± 24.8 vs. 21.5 ± 28.2 ml/min per 1.73 m2; P = 0.011) and a lower prevalence of the Berden sclerotic class (5.9 vs. 20.9%; P = 0.011). Despite a similar crude and adjusted patient survival, the risk of ESKD decreased during p2002 to 2022 (subdistribution hazard ratio [HR] 0.30, 95% confidence interval [CI]: 0.16-0.57; P < 0.001). The results remained significant after accounting for death after ESKD and after adjusting for potential confounders (HR 0.33 [95% CI: 0.18-0.63; P < 0.001]). The risk of relapse was numerically higher during p2002 to 2022 (subdistribution-HR 1.64 [95% CI: 0.95-2.83; P = 0.075]).

Conclusion

MPA kidney involvement has become less severe over the past decades, leading to a reduced risk of ESKD and a higher relapse rate, despite a comparable risk of death.

Subglottic Stenosis as a Presentation of Antineutrophil Cytoplasmic Antibody-Associated Glomerulonephritis

Granulomatosis with polyangiitis (GPA), previously Wegener's granulomatosis, is a necrotizing vasculitic disease process affecting the small- and medium-sized blood vessels. GPA is frequently associated with damage to the respiratory tract and kidneys but often affects other organ systems including the eyes, nasopharynx, and nervous system. Due to the vague nature of presenting symptoms and the progressive nature of GPA, it is essential to keep a broad differential to mitigate the high morbidity and mortality associated with the disease. Here we introduce a case of a GPA presenting as respiratory distress, stridor, and renal injury. We also review common clinical presentations, diagnostic evaluation, and treatment options.

Combination Treatment of Locoregionally Aggressive Granulomatosis with Polyangiitis and Cranial Base Infiltration

OBJECTIVES

To present a personalized approach in three cases of treatment-resistant, locoregionally aggressive forms of cANCA-positive granulomatosis with polyangiitis (GPA) and skull base involvement.

METHODS

Three patients with GPA and skull base involvement were described alongside a critical review of the current literature.

RESULTS

All presented patients suffered from GPA with an inflammatory tumor at the skull base, alongside cerebellopontine angle involvement, cranial nerve palsies, cerebellar disorders, concomitant hearing loss, and severe otalgia. Symptoms were associated with progressive granulomatous destruction of the temporal bone, laryngopharynx, and central nervous system infiltration. Treatment with cyclophosphamide and high doses of glucocorticoid steroids were ineffective but subsequent therapy with rituximab was successful in the presented cases. The literature review showed that the course of the disease with skull base involvement is associated with poorer clinical and radiological responses to standard pharmacotherapies.

CONCLUSION

Granulomatous inflammation localized in the skull base is associated with a more aggressive disease progression and is less likely to respond to pharmacotherapy. Standard induction therapy with cyclophosphamide and glucocorticoid steroids may be ineffective. A better response may be achieved by using rituximab and concomitant local treatment with glucocorticoid steroid injections.

EGPA Phenotyping: Not Only ANCA, but Also Eosinophils

Background: Eosinophilic Granulomatosis with Polyangiitis (EGPA) is a small-vessel necrotizing vasculitis. The anti-neutrophil cytoplasmic antibodies’ (ANCA) role in defining clinical EGPA phenotypes is well established. Although the role of eosinophils in disease pathogenesis has been clearly demonstrated, the value of blood eosinophil count (BEC) as a biomarker of disease phenotypes is currently uncertain. Methods: We retrospectively analyzed EGPA patients referred to our Immunology Clinic. Demographic, laboratory and clinical features were retrieved from clinical records, and a Logistic Regression was fitted to evaluate the predictive power of all baseline clinical and laboratory features to define EGPA phenotypes. Results: 168 patients were recruited. BEC ≤ 1500 cells/mL was predictive of a clinical involvement characterized by asthma, chronic rhinosinusitis with nasal polyps (CRSwNP) and lung opacities (OR 0.18, 95% CI 0.07–0.43; respiratory-limited phenotype); BEC > 3500/mL was predictive of extrapulmonary organ involvement (OR 3.5, 95% CI 1.7–7.1; systemic phenotype). BEC was also predictive of peripheral nervous system (PNS) involvement, with a positive trend with increasing BEC (<1500/mL: OR 0.17, 95%CI, 0.06–0.47; >3500/mL: OR 2.8, 95% CI, 1.5–5.28). ANCA positivity was also predictive of extrapulmonary involvement (OR 4.7, 95% CI 1.9–11.99). Conclusions: according to BEC and irrespective of the ANCA status, two EGPA phenotypes could be identified, named systemic and respiratory-limited phenotypes, with different organ involvement and possibly different prognoses.

Unmet needs in ANCA-associated vasculitis: Physicians' and patients' perspectives

In recent years, clinical research has increased significantly and therapies for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis have improved. However, there are still unanswered questions and unmet needs about AAV patients. The purpose of this review is to examine the frontiers of research related to emerging biomarkers eventually predicting relapse, and new therapeutic approaches, not to mention new quality of life assessment tools. Identifying predictors of relapse may help optimize therapeutic strategies, minimize disease recurrence, and reduce treatment-related side effects. In addition, it is important to recognize that patients may suffer long-term consequences of the disease and its treatment, which, although life-saving, is often associated with significant side effects. Our goal, therefore, is to highlight what has been achieved, the pitfalls, and what still needs to be done, comparing the views of physicians and patients.

Patient-reported outcomes in ANCA-associated vasculitis: a cross-sectional study to explore the interactions between patients' and physicians' perspectives

To evaluate associations between the domains of the ANCA-associated vasculitis patient-reported outcome (AAV-PRO) instrument and clinical variables. Patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA), or renal-limited vasculitis (RLV) were recruited from a tertiary care center in Mexico City. Demographic, clinical, serological, and treatment-related data were retrieved. Disease activity, damage, patient and physician global assessments (PtGA and PhGA) were evaluated. All patients completed the AAV-PRO questionnaire, male patients also completed the International Index of Erectile Function (IIEF-5) questionnaire. Seventy patients (44 women and 26 men) were included, with a median age of 53.5 years (43-61), and a disease duration of 82 months (34-135). Moderate correlations were identified between the PtGA and the AAV-PRO domains: social and emotional impact, treatment side effects, organ-specific symptoms, and physical function. The PhGA correlated with the PtGA and prednisone doses. Subanalyses of the AAV-PRO domains according to sex, age, and disease duration showed significant differences in the treatment side effects domain, with higher scores in women, in patients < 50 years, and in patients with disease duration < 5 years. The domain of concerns about the future showed a higher score in patients with disease duration < 5 years. A total of 17/24 (70.8%) of men who completed the IIEF-5 questionnaire were classified as having some degree of erectile dysfunction. The domains of AAV-PRO correlated with other outcome measures, while differences were found between some of the domains according to sex, age, and disease duration.

Clinical features and management of Chinese anti-neutrophil cytoplasmic antibody-associated vasculitis patients with spontaneous renal hemorrhage: a single-center report and systematic review

INTRODUCTION

Spontaneous renal hemorrhage (SRH) in ANCA-associated vasculitis (AAV) is rare but fatal. We aimed to characterize clinical manifestations and managements of AAV patients with SRH.

METHOD

Hospitalized AAV patients were screened from January 2000 to April 2021, at Peking Union Medical College Hospital (PUMCH). Also, a systematic review was based on retrieving all the relevant literature from PubMed, MedlinePlus, and Web of Science until April 2021. Clinical features, management, and prognosis of the patients were collected and concluded.

RESULTS

In PUMCH, four out of 1640 AAV patients with SRH were included in our study; three had granulomatosis with polyangiitis (GPA) and one had microscopic polyangiitis (MPA). The ratio of men to women was 3 to 1, and the average age of onset was 55 years. The Birmingham Vasculitis Activity Score (BVAS) ranged from 21 to 23. Combining with documented reports, 13 patients were diagnosed as AAV complicated with SRH (including four from PUMCH), 7 with GPA, and 6 with MPA. Mean BVAS was 25.2 ± 6.6. The symptoms of SRH presented as severe back or abdominal pain. Patients with SRH to age- and gender-matched patients without SRH were compared, and we found that in the SRH group, the duration of disease was shorter, and BVAS, renal function, and inflammatory markers (WBC and ESR) were significantly greater, whereas Hb, Alb, and renal function greatly reduced.

CONCLUSION

This is the first summary of clinical features and treatments of SRH in AAV. Patients with AAV in early stage and with high disease activity appeared to be more likely to develop SRH. Key Points • This is the first summary of clinical features and treatments of SRH in AAV. • SRH more likely occurs in AAV patients in the early stage (≤ 3 months) and with high disease activity. • Clinicians should be aware of the possibility of SRH when AAV patients complain of back or abdominal pain.

Review of systemic sclerosis and antineutrophil cytoplasmic antibody vasculitis overlap: Using autoantibodies for a personalised medicine approach

Both antineutrophil cytoplasmic antibody-associated vasculitis and systemic sclerosis are rare autoimmune diseases. Both have the potential for significant multi-organ involvement, and both carry high morbidity and mortality. Disease-specific autoantibodies in these conditions allow for risk stratification for organ-based complications, and for personalised therapeutic strategies. The concomitant presentation of antineutrophil cytoplasmic antibody-associated vasculitis and systemic sclerosis is rare, and only reported in up to 1.3% of systemic sclerosis cases. These patients present more frequently with anti-myeloperoxidase and anti-topoisomerase antibody profiles, with increased incidence of interstitial lung disease and renal involvement than would be expected in either disease independently. Appreciating the role of the autoantibodies in each disease state, and where they overlap, allows for the potential of a more personalised approach to managing these complex patients.

A Decade of Clinical Advances in Chronic Rhinosinusitis: 2012-2022

The field of chronic rhinosinusitis (CRS) is constantly evolving. In the past 10 years, key advancements in basic and translational research as well as clinical studies have improved our understanding and management of CRS. Notably, treatment options have expanded to include novel therapeutic drugs, devices, and surgical techniques. Assessments of patient symptoms and their impact on quality of life have become more standardized. Progress has also been made in both determining the true prevalence of CRS and recognizing comorbidities that can impact CRS severity. Practice guidelines have also shifted from expert opinion to more data-driven analyses. This review highlights major clinical advancements made in the field of CRS over the past 10 years as well as identifies current gaps in knowledge that can form the basis for new areas of study over the next decade.

Neutrophils in autoimmunity: when the hero becomes the villain

Neutrophils were long considered to be a short-lived homogenous cell population, limited to their role as first responders in anti-bacterial and -fungal immunity. While it is true that neutrophils are first to infiltrate the site of infection to eliminate pathogens, growing evidence suggests their functions could extend beyond those of basic innate immune cells. Along with their well-established role in pathogen elimination, utilizing effector functions such as phagocytosis, degranulation, and the deployment of neutrophil extracellular traps (NETs), neutrophils have recently been shown to possess antigen-presenting capabilities. Moreover, the identification of different subtypes of neutrophils points to a multifactorial heterogeneous cell population with great plasticity in which some subsets have enhanced pro-inflammatory characteristics, while others seem to behave as immunosuppressors. Interestingly, the aberrant presence of activated neutrophils with a pro-inflammatory profile in several systemic and organ-specific autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc), multiple sclerosis (MS), and type 1 diabetes (T1D) could potentially be exploited in novel therapeutic strategies. The full extent of the involvement of neutrophils, and more specifically that of their various subtypes, in the pathophysiology of autoimmune diseases is yet to be elucidated.

Role of complement activation in anti-neutrophil cytoplasmic antibody-associated glomerulonephritis

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is an autoimmune disease characterized by necrotizing inflammation of small or medium vessels, causing ANCA associated glomerulonephritis (AAGN). AAGN is defined as pauci-immune glomerulonephritis with no or little immune deposition; hence, activation of the complement system in AAV was overlooked until recently. However, many studies in mice and humans have revealed a crucial role for complement system activation in the development of AAGN. Circulating and urinary detection of various complement components associated with AP activation, which have been broadly correlated with the clinical activity of AAGN, has been reported and may be useful for predicting renal outcome at the time of diagnosis and setting up personalized treatments. Moreover, recent investigations have suggested the possible contribution of the complement classical or lectin pathway activation in the development of AAGN. Thus, as therapeutic options targeting complement components are making rapid strides, the primary complement pathway involved in AAGN disease progression remains to be elucidated: this will directly impact the development of novel therapeutic strategies with high specificity and reduced side effects. This review summarizes and discusses the most recent evidence on the crucial roles of the complement system in the development of AAGN and possible therapeutic strategies that target complement components for disease management.

Eosinophilic granulomatosis with polyangiitis: case report and literature review

Eosinophilic granulomatosis with polyangiitis (EGPA), previously known as Churg-Strauss syndrome, is a multisystem disorder characterised by asthma, blood and tissue eosinophilia and small-vessel vasculitis. Eosinophilic tissue infiltration and extravascular granuloma formation can lead to damage in any organ, but it is classically seen to cause pulmonary infiltrates, sino-nasal disease, peripheral neuropathy, renal and cardiac involvement, and rashes. EGPA is part of the anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis syndromes, with the antibody being detected in ∼30-40% of cases and mostly against myeloperoxidase. Two genetically and clinically distinct phenotypes, defined by the presence or absence of ANCA have been identified. Treatment for EGPA focuses on inducing and maintaining disease remission. To date, oral corticosteroids remain first-line agents whilst second-line treatments include immunosuppressants such as cyclophosphamide, azathioprine, methotrexate, rituximab and mycophenolate mofetil. However, long-term steroid usage results in multiple and well-known adverse health effects and new insights into the pathophysiology of EGPA have allowed for the development of targeted biologic therapies, like the anti-eosinophilic, anti-interleukin-5 monoclonal antibodies.

Myeloperoxidase: Regulation of Neutrophil Function and Target for Therapy

Neutrophils, the most abundant white blood cells in humans, are critical for host defense against invading pathogens. Equipped with an array of antimicrobial molecules, neutrophils can eradicate bacteria and clear debris. Among the microbicide proteins is the heme protein myeloperoxidase (MPO), stored in the azurophilic granules, and catalyzes the formation of the chlorinating oxidant HOCl and other oxidants (HOSCN and HOBr). MPO is generally associated with killing trapped bacteria and inflicting collateral tissue damage to the host. However, the characterization of non-enzymatic functions of MPO suggests additional roles for this protein. Indeed, evolving evidence indicates that MPO can directly modulate the function and fate of neutrophils, thereby shaping immunity. These actions include MPO orchestration of neutrophil trafficking, activation, phagocytosis, lifespan, formation of extracellular traps, and MPO-triggered autoimmunity. This review scrutinizes the multifaceted roles of MPO in immunity, focusing on neutrophil-mediated host defense, tissue damage, repair, and autoimmunity. We also discuss novel therapeutic approaches to target MPO activity, expression, or MPO signaling for the treatment of inflammatory and autoimmune diseases.