Treatment response and relapse in antineutrophil cytoplasmic autoantibody-associated microscopic polyangiitis and glomerulonephritis

Unravelling the Link between the Gut Microbiome and Autoimmune Kidney Diseases: A Potential New Therapeutic Approach

The gut microbiota and short chain fatty acids (SCFA) have been associated with immune regulation and autoimmune diseases. Autoimmune kidney diseases arise from a loss of tolerance to antigens, often with unclear triggers. In this review, we explore the role of the gut microbiome and how disease, diet, and therapy can alter the gut microbiota consortium. Perturbations in the gut microbiota may systemically induce the translocation of microbiota-derived inflammatory molecules such as liposaccharide (LPS) and other toxins by penetrating the gut epithelial barrier. Once in the blood stream, these pro-inflammatory mediators activate immune cells, which release pro-inflammatory molecules, many of which are antigens in autoimmune diseases. The ratio of gut bacteria Bacteroidetes/Firmicutes is associated with worse outcomes in multiple autoimmune kidney diseases including lupus nephritis, MPO-ANCA vasculitis, and Goodpasture's syndrome. Therapies that enhance SCFA-producing bacteria in the gut have powerful therapeutic potential. Dietary fiber is fermented by gut bacteria which in turn release SCFAs that protect the gut barrier, as well as modulating immune responses towards a tolerogenic anti-inflammatory state. Herein, we describe where the current field of research is and the strategies to harness the gut microbiome as potential therapy.

Clinical features and prognosis of ANCA-associated vasculitis patients who were double-seropositive for myeloperoxidase-ANCA and proteinase 3-ANCA

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) patients with dual positivity for proteinase 3-ANCA (PR3-ANCA) and myeloperoxidase-ANCA (MPO-ANCA) are uncommon. We aimed to investigate these idiopathic double-positive AAV patients' clinical features, histological characteristics, and prognosis. We reviewed all the electronic medical records of patients diagnosed with AAV to obtain clinical data and renal histological information from January 2010 to December 2020 in a large center in China. Patients were assigned to the MPO-AAV group or PR3-AAV group or idiopathic double-positive AAV group by ANCA specificity. We explored features of idiopathic double-positive AAV. Of the 340 patients who fulfilled the study inclusion criteria, 159 (46.76%) were female, with a mean age of 58.41 years at the time of AAV diagnosis. Similar to MPO-AAV, idiopathic double-positive AAV patients were older and had more severe anemia, lower Birmingham Vasculitis Activity Score (BVAS) and C-reactive protein (CRP) levels, less ear, nose, and throat (ENT) involvement, higher initial serum creatinine and a lower estimated glomerular filtration rate (eGFR) when compared with PR3-AAV (P < 0.05). The proportion of normal glomeruli of idiopathic double-positive AAV was the lowest among the three groups (P < 0.05). The idiopathic double-positive AAV patients had the worst remission rate (58.8%) among the three groups (P < 0.05). The relapse rate of double-positive AAV (40.0%) was comparable with PR3-AAV (44.8%) (P > 0.05). Although there was a trend toward a higher relapse rate of idiopathic double-positive AAV (40.0%) compared with MPO-AAV (23.5%), this did not reach statistical significance (P > 0.05). The proportion of patients who progressed to ESRD was 47.1% and 44.4% in the idiopathic double-positive AAV group and MPO-AAV group respectively, without statistical significance. Long-term patient survival also varied among the three groups (P < 0.05). Idiopathic double-positive AAV is a rare clinical entity with hybrid features of MPO-AAV and PR3-AAV. MPO-AAV is the "dominant" phenotype in idiopathic double-positive AAV.

Antineutrophil Cytoplasmic Antibody-Associated Vasculitis and the Risk of Developing Incidental Tuberculosis: A Population-Based Cohort Study

Background and Objectives: Treatment for antineutrophil cytoplasmic antibody-associated vasculitis (AAV) must deal with immunosuppression, as well as infections associated with a compromised immune system, such as tuberculosis (TB). Our aim was to examine the risk of incidental TB after diagnosis of AAV. Materials and Methods: This retrospective population-based cohort study was based on the data from the National Health Insurance Research Database in Taiwan. Patients with newly diagnosed granulomatous polyangiitis or microscopic polyangiitis were identified between 1 January 2000 and 31 December 2012. The primary outcome was risk of incidental TB. Cox proportional hazard models were used to evaluate the association between AAV and incidental TB. Results: A total of 2257 patients with AAV and a propensity-score matched cohort of 9028 patients were studied. Overall, patients with AAV were at a 1.48× higher risk of contracting incidental TB than the patients in the matched cohort (adjusted HR 1.48; 95% confidence interval [CI], 1.02-2.15). Note that the highest risk of contracting incidental TB was in the first two years following a diagnosis of AAV, with a nearly 1-fold increase in risk (adjusted HR, 1.91; 95% CI, 1.01-3.60). Female AAV patients were 3.24× more likely than females without AAV to develop TB (adjusted HR 3.24; 95% CI, 1.85-5.67). Conclusions: Patients with AAV exhibit a 48% elevated TB risk, notably, a 91% increase within the first two years postdiagnosis. Female AAV patients face a 3.24 times higher TB risk compared to females without AAV. This study is limited by potential misclassification and overestimation of AAV cases. Clinicians should closely monitor TB risk in AAV patients, especially in females and the initial two years following diagnosis.

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

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

Development of a radiomics nomogram to predict the treatment resistance of Chinese MPO-AAV patients with lung involvement: a two-center study

Background

Previous studies from our group and other investigators have shown that lung involvement is one of the independent predictors for treatment resistance in patients with myeloperoxidase (MPO)-anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-AAV). However, it is unclear which image features of lung involvement can predict the therapeutic response in MPO-AAV patients, which is vital in decision-making for these patients. Our aim was to develop and validate a radiomics nomogram to predict treatment resistance of Chinese MPO-AAV patients based on low-dose multiple slices computed tomography (MSCT) of the involved lung with cohorts from two centers.

Methods

A total of 151 MPO-AAV patients with lung involvement (MPO-AAV-LI) from two centers were enrolled. Two different models (Model 1: radiomics signature; Model 2: radiomics nomogram) were built based on the clinical and MSCT data to predict the treatment resistance of MPO-AAV with lung involvement in training and test cohorts. The performance of the models was assessed using the area under the curve (AUC). The better model was further validated. A nomogram was constructed and evaluated by DCA and calibration curves, which further tested in all enrolled data and compared with the other model.

Results

Model 2 had a higher predicting ability than Model 1 both in training (AUC: 0.948 vs. 0.824; p = 0.039) and test cohorts (AUC: 0.913 vs. 0.898; p = 0.043). As a better model, Model 2 obtained an excellent predictive performance (AUC: 0.929; 95% CI: 0.827-1.000) in the validation cohort. The DCA curve demonstrated that Model 2 was clinically feasible. The calibration curves of Model 2 closely aligned with the true treatment resistance rate in the training (p = 0.28) and test sets (p = 0.70). In addition, the predictive performance of Model 2 (AUC: 0.929; 95% CI: 0.875-0.964) was superior to Model 1 (AUC: 0.862; 95% CI: 0.796-0.913) and serum creatinine (AUC: 0.867; 95% CI: 0.802-0.917) in all patients (all p< 0.05).

Conclusion

The radiomics nomogram (Model 2) is a useful, non-invasive tool for predicting the treatment resistance of MPO-AAV patients with lung involvement, which might aid in individualizing treatment decisions.

An unusual form of kidney injury without glomerulonephritis in microscopic polyangiitis: a case report

BACKGROUND

Microscopic polyangiitis (MPA), a kind of antineutrophil cytoplasmic autoantibody associated vasculitis (AAV), predominantly affects small-sized vessels. MPA is a significant cause of the pulmonary-renal syndrome. Pauci-immune necrotizing and crescentic glomerulonephritis is the typical renal histological feature of AAV. Tubulointerstitial lesions may occur and mostly form with inflammatory cell infiltration in the interstitium. However, a few cases reported only tubulointerstitial involvement without glomerular lesions in patients with MPA.

CASE PRESENTATION

We present an MPA case, a 70-year-old male patient diagnosed with acute kidney injury accompanying the dialysis requirement. Only acute tubulointerstitial nephritis was revealed in kidney biopsy without evidence of glomerular injury. Also, interstitial pulmonary fibrosis was determined on computerized tomography, and myeloperoxidase antineutrophil cytoplasmic autoantibody was positive. Consequently, we have considered the main diagnosis as MPA. We did not prefer a standard tubulointerstitial nephritis treatment regimen due to the presence of life-threatening systemic vasculitis. Treatment was established like crescentic glomerulonephritis. Induction therapy consisted of pulse steroid, cyclophosphamide, and plasmapheresis. Unfortunately, severe SARS-CoV-2 infection caused death during induction therapy in this case.

CONCLUSIONS

The lack of glomerular injury and solely interstitial inflammation is atypical regarding AAV involvement in the kidney. This diversity might be initially considered as only a simple histological elaboration. However, it is a significant entity for guiding the treatment of AAV.

Risk factors associated with cytomegalovirus reactivation in patients receiving immunosuppressive therapy for rheumatic diseases: a retrospective study

Immunosuppressive treatment is a common cause of cytomegalovirus (CMV) reactivation. However, there is no consensus regarding the risk factors for CMV reactivation in rheumatic diseases. Therefore, this study aimed to elucidate the risk factors associated with CMV reactivation. We retrospectively collected the data of 472 patients with rheumatic diseases whose CMV pp65 antigen (C7-HRP) titer was measured. We divided the patients into those with and those without C7-HRP. We retrospectively collected data on age, sex, primary condition and organ involvement, and blood test results. We also investigated the use of immunosuppressants and the maximum and cumulative doses of prednisolone (PSL). We performed univariate and multivariate analyses to identify risk factors for CMV reactivation. Multivariate analysis showed that higher age (71.2 vs. 64.4 years, p = 0.0022), hypoalbuminemia (2.9 vs. 3.4 g/dL, p = 0.0104), higher creatinine level (1.2 vs. 0.9 mg/dL, p = 0.0026), cyclosporine use (8.2 vs. 3.6%, p = 0.0101), and higher maximum (552.4 vs. 243.3 mg, p < 0.0001) and cumulative (2785.9 vs. 1330.5 mg, p < 0.0001) doses of PSL were associated with CMV reactivation. Older age, hypoalbuminemia, higher creatinine level, cyclosporine use, and higher maximum and cumulative doses of PSL were significant risk factors for CMV reactivation in rheumatic diseases.

Relevance of Combined Clinicopathologic Phenotype and Antineutrophil Cytoplasmic Autoantibody Serotype in the Diagnosis of Antineutrophil Cytoplasmic Autoantibody Vasculitis

Introduction

Granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA), 2 major clinicopathologic variants of antineutrophil cytoplasmic autoantibody (ANCA) vasculitides, are mostly associated with proteinase 3 (PR3)-ANCA and myeloperoxidase (MPO)-ANCA, respectively. Less is known regarding the uncommon forms of ANCA vasculitis, PR3-ANCA MPA and MPO-ANCA GPA.

Methods

In this cohort study we detailed the clinical presentation and outcome of patients with PR3-ANCA MPA and MPO-ANCA GPA from the Glomerular Disease Collaborative Network (GDCN) inception cohort. Baseline clinical manifestations, relapses, end-stage kidney disease (ESKD), and survival were compared within MPA cases by PR3-ANCA (n = 116) versus MPO-ANCA (n = 173) and within GPA cases by PR3-ANCA (n = 108) versus MPO-ANCA (n = 43). Fisher's exact test and Wilcoxon two sample test were used for comparisons. Proportional hazards models were used to evaluate the development of relapses, ESKD, and death.

Results

Patients with PR3-ANCA MPA were younger (53 years vs. 62 years, P = 0.0007) and had increased prevalence of joint involvement (56% vs. 40%, P = 0.0115) and ear, nose, and throat (ENT) involvement (44% vs. 26%, P = 0.002) than MPO-ANCA MPA. Relapses, ESKD, and survival were similar between both MPA subsets. Within the GPA group, patients with MPO-ANCA GPA were older (61 years vs. 46 years, P = 0.0007) and more likely female (56% vs. 35%, P = 0.027) than PR3-ANCA GPA patients. MPO-ANCA GPA was also characterized by less prevalent ENT manifestations (58% vs. 77%, P = 0.028) and neurologic manifestations (5% vs. 25%, P = 0.0029), and increased ESKD and mortality.

Conclusions

PR3-ANCA MPA and MPO-ANCA GPA are clinicopathologically distinct subsets of ANCA vasculitis that differ from MPO-ANCA MPA and PR3-ANCA GPA. Although the impact of these differences on the clinical management and outcome warrants further evaluation, these results support the recommendation of including both the phenotypic diagnosis and ANCA serotype in the diagnosis of ANCA vasculitis.

Glucocorticoid therapy in respiratory illness: bench to bedside

Each year, hundreds of millions of individuals are affected by respiratory disease leading to approximately 4 million deaths. Most respiratory pathologies involve substantially dysregulated immune processes that either fail to resolve the underlying process or actively exacerbate the disease. Therefore, clinicians have long considered immune-modulating corticosteroids (CSs), particularly glucocorticoids (GCs), as a critical tool for management of a wide spectrum of respiratory conditions. However, the complex interplay between effectiveness, risks and side effects can lead to different results, depending on the disease in consideration. In this comprehensive review, we present a summary of the bench and the bedside evidence regarding GC treatment in a spectrum of respiratory illnesses. We first describe here the experimental evidence of GC effects in the distal airways and/or parenchyma, both in vitro and in disease-specific animal studies, then we evaluate the recent clinical evidence regarding GC treatment in over 20 respiratory pathologies. Overall, CS remain a critical tool in the management of respiratory illness, but their benefits are dependent on the underlying pathology and should be weighed against patient-specific risks.

Renal Expression of Annexin A1 Is Associated With the Severity of Renal Injury in Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis

Background

Increasing studies demonstrated the importance of activation of neutrophils in the pathogenesis of antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). Previous studies showed that annexin A1 (ANXA1) inhibited the recruitment, transendothelial migration and respiratory burst of neutrophils and induced apoptosis of neutrophils. The current study aimed to investigate the plasma and renal levels of ANXA1 as well as their association with the disease severity in AAV patients.

Methods

Thirty-one AAV patients in active stage and 35 AAV patients in remission stage were recruited. The expression of ANXA1 in renal specimens was assessed by immunohistochemistry. The co-localization of ANXA1 with renal intrinsic and infiltrating cells was detected by double immunofluorescence. The plasma levels of ANXA1 were determined by ELISA. The association of plasma and renal levels of ANXA1 with clinicopathological parameters was further analyzed.

Results

Plasma levels of ANXA1 were significantly higher in active AAV patients than those in AAV patients in remission as well as healthy controls. The renal expression of ANXA1 was significantly higher in active AAV patients than in healthy controls and disease controls. Double immunofluorescence assay showed that ANXA1 was expressed in glomerular endothelial cells, mesangial cells, podocytes, proximal tubular epithelial cells, neutrophils, monocytes/macrophages and T cells in AAV patients. The mean optical density of ANXA1 in glomeruli was correlated with serum creatinine levels (r = −0.491, P = 0.005) and eGFR (r = 0.492, P = 0.005) at renal biopsy and the proportion of crescents (r = −0.423, P = 0.018) in renal specimens of AAV patients. The expression of ANXA1 in glomeruli of AAV patients achieving complete renal recovery was significantly higher than those achieving partial renal recovery.

Conclusion

In AAV patients, the renal expression of ANXA1 was associated with the severity of renal injury.

A meta-analysis of the safety and efficacy of maintenance therapies for anti-neutrophil cytoplasmic antibody small-vessel vasculitis

Introduction

To compare the efficacy and safety of different regimens used for maintenance of remission in patients with antineutrophil cytoplasmic antibody (ANCA) vasculitis.

Methods

This network meta-analysis studied adult patients with ANCA vasculitis in complete remission, who were maintained with various regimens, excluding patients with eosinophilic granulomatosis with polyangiitis (GPA) and those who have ended up in end-stage kidney disease. Outcomes of interest included relapse (any/major), relapse-free survival, and adverse effects. PubMed, Scopus, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov, and Google Scholar were systematically searched from inception.

Results

Overall, the meta-analysis was based on 10 reports, describing the outcomes of 7 randomized controlled trials (RCTs) including 752 patients with ANCA vasculitis. Relapse-free survival was significantly worse with the use of azathioprine (hazard ratio [HR]: 2.11, 95% CI: 1.19–3.74), methotrexate (HR: 2.51, 95% CI: 1.24–5.08), and mycophenolate mofetil (HR: 3.57, 95% CI: 1.70–7.46) compared with the use of rituximab. Outcomes estimated for azathioprine (HR: 0.59, 95% CI: 0.37–0.94), cyclophosphamide (HR: 0.39, 95% CI: 0.20–0.75), and leflunomide (HR: 0.30, 95% CI: 0.11–0.84) were better than those for mycophenolate mofetil. When examining relapse-free survival, relapses were more likely with use of azathioprine (odds ratio [OR]: 2.15, 95% CI: 1.00–4.59) and mycophenolate mofetil (OR: 4.42, 95% CI: 1.63–11.94) compared with the use of rituximab. The risk of major relapse calculated for azathioprine (OR: 2.39, 95% CI: 1.10–5.19), methotrexate (OR: 3.18, 95% CI: 1.14–8.89), and mycophenolate mofetil (OR: 5.20, 95% CI: 1.65–16.37) was higher than that for rituximab. The rates of serious adverse effects did not differ significantly among interventions.

Conclusion

Rituximab appears predominant in maintaining remission in patients with ANCA vasculitis with no cost in adverse events.

The Impact of High Dose Glucocorticoids on Bone Health and Fracture Risk in Systemic Vasculitides

Systemic vasculitides are a range of conditions characterized by inflammation of blood vessels which may manifest as single organ or life-threatening multisystem disease. The treatment of systemic vasculitis varies depending on the specific disease but historically has involved initial treatment with high dose glucocorticoids alone or in conjunction with other immunosuppressive agents. Prolonged glucocorticoid treatment is frequently required as maintenance treatment. Patients with small and large vessel vasculitis are at increased risk of fracture. Osteoporosis may occur due to intrinsic factors such as chronic inflammation, impaired renal function and to a large extent due to pharmacological therapy with high dose glucocorticoid or combination treatments. This review will outline the known mechanism of bone loss in vasculitis and will summarize factors attributing to fracture risk in different types of vasculitis. Osteoporosis treatment with specific consideration for patients with vasculitis will be discussed. The use of glucocorticoid sparing immunosuppressive agents in the treatment of systemic vasculitis is a significant area of ongoing research. Adjunctive treatments are used to reduce cumulative doses of glucocorticoids and therefore may significantly decrease the associated fracture risk in patients with vasculitis. Lastly, we will highlight the many unknowns in the relation between systemic vasculitis, its treatment and bone health and will outline key research priorities for this field.

Immunoadsorption Improves Remission Rates of Patients with Antineutrophil Cytoplasmic Antibody-Associated Vasculitis and Severe Kidney Involvement

INTRODUCTION

The role of plasma exchange in treatment of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) with severe kidney involvement is controversial. It is urgent to find effective treatments to improve prognosis of AAV patients. In this retrospective study, the outcomes of immunoadsorption (IA) onto protein A in AAV patients with severe kidney involvement were evaluated.

METHODS

Clinical data of 60 patients with AAV and severe kidney involvement were analyzed. Patients received cyclophosphamide or rituximab for remission induction, among which 16 were additionally treated with IA. Remission, end-stage kidney disease (ESKD), death, and relapse were compared.

RESULTS

Of 60 patients, 56 patients (93.3%) were positive for myeloperoxidase (MPO)-ANCA. At diagnosis, the estimated glomerular filtration rate and Birmingham Vasculitis Activity Score (BVAS) was 13.0 (7.7, 18.7) mL/min/1.73 m2 and 11.1 ± 3.4, respectively. After 3-17 days (mean 10.4 days) of induction treatment, the disease activity decreased more obviously in the IA group (p = 0.022) than the control group. IA showed superior over standard regimen in clearance of MPO-ANCA within 3-31 days (median 11 days) after treatment (78.4% vs. 9.3%, p = 0.005). After a median follow-up of 20.2 months, remission was achieved more quickly (p = 0.035) and higher (hazard ratio (HR) = 2.3, 95% confidence interval (CI): 1.1∼7.2, p = 0.033) in the IA group than the control group. IA therapy showed an advantage in reducing death (HR = 0.2, 95% CI: 0.1∼0.9, p = 0.032). There was no difference in developing into ESKD in both groups (HR = 0.7, 95% CI: 0.3∼2.0, p = 0.504). Multivariate Cox regression analysis indicated that early-stage remission was an independent predictor for ESKD (HR = 0.03, 95% CI: 0.003∼0.25, p = 0.001) and death (HR = 0.07, 95% CI: 0.01∼0.51, p = 0.009).

CONCLUSION

IA treatment induces quicker and higher remission and lower mortality in AAV patients with severe kidney involvement. The early remission independently predicts the outcomes for these patients.

Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis in Kidney Transplantation

Due to complex comorbidity, high infectious complication rates, an elevated risk of relapsing for primary renal disease, as well as inferior recipient and allograft survivals, individuals with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAVs) are often considered as poor transplant candidates. Although several aspects of recurrent and de novo AAVs remain unclear, recent evidence suggests that kidney transplantation (KT) represents the best option, which is also the case for this particular subgroup of patients. Special counselling and individualized approaches are strongly recommended at the time of enlistment and during the entire post-transplant follow-up. Current strategies include avoiding transplantation within one year of complete clinical remission and thoroughly assessing the recipient for early signs of renal or systemic vasculitis. The main clinical manifestations of allograft AAV are impaired kidney function, proteinuria, and hematuria with ANCA positivity in most cases. Mixed results have been obtained using high-dose steroids, mycophenolate mofetil, or cyclophosphamide. The aim of the present review was to summarize the available literature on AAVs in KT, particularly focusing on de novo pauci-immune glomerulonephritis.

Nation-wide survey of the treatment trend of microscopic polyangiitis and granulomatosis with polyangiitis in Japan using the Japanese Ministry of Health, Labour and Welfare Database

OBJECTIVES

In Japan, clinical records of patients with intractable diseases, including microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA), are compiled into a database. This study aimed to understand the current treatment status and changes in treatment regimens from our previous survey.

METHODS

Using data from 2012 and 2013, patients with new-onset MPA and GPA were extracted and analysed.

RESULTS

We analysed 1278 MPA and 215 GPA patients. The average age was 71.7 and 62.7 years, respectively. Methylprednisolone pulse therapy was used in 51.2% of MPA patients and 40.5% of GPA patients; the initial prednisolone-equivalent glucocorticoid dose was 39.5 mg/day in MPA and 46.6 mg/day in GPA. Concomitant intravenous or oral cyclophosphamide (CY) was administered to 22.6% of MPA and 56.3% of GPA. Young age, bloody sputum, low serum creatinine, and high C-reactive protein levels were independently associated with CY use in MPA. Compliance with treatment protocol for Japanese patients with myeloperoxidase (MPO)-anti-neutrophilic cytoplasmic antibody-associated vasculitis study criteria or the 2011 clinical practice guidelines for rapidly progressive glomerulonephritis was 42.7% and 49.7%, respectively.

CONCLUSIONS

MPA was more prevalent than GPA in the registry. Compared to patients with GPA, MPA patients were older and used CY less frequently. No apparent changes in treatment trends were observed from the previous survey.

Hypocomplementemia at Diagnosis of Pauci-immune Glomerulonephritis Is Associated With Advanced Histopathological Activity Index and High Probability of Treatment Resistance

Introduction

Recent evidence suggests that complement activation is important in the pathogenesis of pauci-immune (PI) vasculitis. This is a retrospective investigation of the frequency of hypocomplementemia at pauci-immune glomerulonephritis (PIGN) diagnosis, in relation to vasculitic manifestations, renal histopathology, and treatment outcomes.

Methods

A total of 115 patients with biopsy-proven PIGN were categorized based on their serum complement C3 (sC3). Histopathology evaluation included activity and chronicity indexes. The primary outcome of interest was treatment resistance, defined as a progressive decline in kidney function, with persistently active urine sediment, leading to dialysis dependency or vasculitis-related death.

Results

In all, 20.9% of patients had low sC3 levels associated with more advanced renal impairment (P < 0.01), requiring acute dialysis (P < 0.01) more frequently compared to patients with normal sC3. Within 1 year, 85.7% of patients with normal sC3 responded to therapy, versus 58.3% of those with low sC3 (P = 0.001). The probability of treatment resistance was strongly associated with low sC3 (P = 0.004), high serum creatinine (P < 0.001), acute dialysis requirement (P < 0.001), and high histopathological score of chronicity (P < 0.01). Advanced histopathological activity was related to more intense interstitial leukocyte infiltration (P = 0.005) and higher likelihood of fibrinoid necrosis documentation in a vessel wall (P = 0.02). The probability of treatment resistance was higher in patients with low sC3 (odds ratio [OR] = 6.47, 95% confidence interval [CI] 1.47-28.35, P = 0.013), oliguria (OR = 29.57, 95% CI = 4.74-184, P < 0.0001), and high chronicity score (OR = 1.77, 95% CI = 1.23-2.54, P = 0.002).

Conclusion

Low sC3 is emerging as an independent predictor of treatment resistance in patients with PIGN associated with higher index of histopathological activity at diagnosis compared to normal sC3.

Looks can be Deceiving: A Challenging Case of Anti-Neutrophil Cytoplasmic Autoantibody Associated Vasculitis

[Anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis] (AAV) is an autoimmune disease characterized by systemic vascular inflammation. We present a case of a 76-year-old man who presented with shortness of breath, fatigue, and weakness. He was eventually diagnosed with hydralazine-induced ANCA-associated renal limited glomerulonephritis. The presentation of this case was unique for a few reasons; the patient showed an initial improvement in kidney function, was non-oliguric, and had no systemic signs of vasculitis. This led to the patient being discharged prematurely with the diagnosis of acute tubular necrosis. We discuss educational features of this case and warn future clinicians about the possibility of waxing and waning renal function in these patients, as well as the importance of having a higher index of suspicion for glomerulonephritis in patients who take hydralazine.

Life-Threatening Diffuse Alveolar Hemorrhage as an Initial Presentation of Microscopic Polyangiitis: COVID-19 as a Likely Culprit

Microscopic polyangiitis (MPA) is a systemic small vessel vasculitis but it is rare to see life-threatening diffuse alveolar hemorrhage (DAH) in MPA as an initial presentation. MPA more commonly presents with renal involvement and develops pulmonary manifestations later in the disease course. Our patient is a 77-year-old female with a recent history of recovered COVID-19 infection who presented with sudden onset fever, dyspnea, and hemoptysis for three days. She was diagnosed with MPA because of the new-onset DAH, a strongly positive myeloperoxidase (MPO) antibody, and the low likelihood of another etiology. The patient was treated with pulse-dose steroids and plasmapheresis while being on mechanical ventilation. This case highlights the importance of the prompt recognition of DAH as an initial presentation of MPA and illustrates the possible role of COVID-19 in inciting autoimmune conditions.

ANCA-Associated Vasculitis: An Update

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) represents a group of small vessel vasculitides characterized by granulomatous and neutrophilic tissue inflammation, often associated with the production of antibodies that target neutrophil antigens. The two major antigens targeted by ANCAs are leukocyte proteinase 3 (PR3) and myeloperoxidase (MPO). AAV can be classified into 3 categories based on patterns of clinical involvement: namely, granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic GPA (EGPA). Clinically, AAV involves many organ systems including the lungs, kidneys, skin, and nervous system. The prognosis of AAV has improved dramatically due to advances in the understanding of its pathogenesis and treatment modalities. This review will highlight some of the recent updates in our understanding of the pathogenesis, clinical manifestations, and treatment options in patients with AAV focusing on kidney involvement.

A Case of Microscopic Polyangiitis Presenting as Cranial Giant Cell Arteritis

We present a case of a 63-year old man with microscopic polyangiitis (MPA) in which the initial clinical presentation resembled the cranial form of giant cell arteritis (GCA) (headache, jaw claudication, low grade fever and raised inflammation markers). Ultrasound of both superficial common temporal arteries revealed signs indicative of vessel wall inflammation. Based on clinical picture and compatible imaging findings, treatment with corticosteroids for GCA was started. After initial improvement and steroid tapering, lung infiltrations, mononeuritis of the right peroneal nerve and cutaneous necrosis appeared and p-Antineutrophil cytoplasmic antibodies (ANCA) turned out to be positive. Three intravenous cyclophosphamide pulses for MPA led in disease remission and maintenance treatment with azathioprine followed. Two years later, the patient has no symptoms and laboratory parameters are normal. This case highlights that MPA can affect temporal arteries and can masquerade as cranial GCA.

Proposal for a more practical classification of antineutrophil cytoplasmic antibody-associated vasculitis

The nomenclature for antineutrophil cytoplasmic antibody (ANCA)-associated kidney disease has evolved from honorific eponyms to a descriptive-based classification scheme (Chapel Hill Consensus Conference 2012). Microscopic polyangiitis, granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis do not correlate with presentation, response rates and relapse rates as when comparing myeloperoxidase versus leukocyte proteinase 3. Here we discuss the limitations of the currently used classification and propose an alternative, simple classification according to (i) ANCA type and (ii) organ involvement, which provides important clinical information of prognosis and outcomes.

Checkpoint inhibitor-related renal vasculitis and use of rituximab

The percentage of patients with cancer eligible for checkpoint inhibitor (CPI) therapy has increased rapidly over the past few years and approaches 45%. As a result, more cases of CPI-related nephrotoxicity, including a rare subset with vasculitis, are being reported. To elucidate the clinical presentation of CPI-associated renal vasculitis and its possible mechanisms, treatment options and prognosis, we describe cases from a comprehensive cancer center and reviewed the literature for similar cases. We retrospectively reviewed the charts of all patients with cancer from 2014 to 2020 who were diagnosed with CPI-related nephrotoxicity and underwent a kidney biopsy. We identified five cases of renal vasculitis: three patients were diagnosed with seronegative antineutrophil cytoplasm antibody (ANCA)-associated vasculitis, one case with seropositive ANCA-associated vasculitis and one case was diagnosed with IgA vasculitis. Of these cases, four patients were receiving nivolumab, and one patient was receiving tremelimumab. All patients had microscopic hematuria, four out of five patients had negative ANCA serology, one patient had concurrent lung involvement and positive ANCA serology, and all had severe acute kidney injury with creatinine >4.50 mg/dL on diagnosis. All patients were treated by discontinuing CPI and initiating corticosteroids and rituximab. Three patients received plasmapheresis; two of these required renal replacement therapy including the patient with lung involvement. All patients after rituximab had a partial or complete renal response. Two patients died within 8 months of diagnosis due to malignancy progression. None of the patients had a relapse of vasculitis. We demonstrated that CPI can be associated with different types of renal vasculitis that are predominantly ANCA negative and manifest as severe acute kidney injury. Despite the lack of strong evidence, treatment similar to treatment of primary seropositive ANCA-associated vasculitis with corticosteroids and rituximab is well tolerated with favorable renal outcomes.

Granulomatosis with polyangiitis (Wegener's)

Granulomatosis with polyangiitis (GPA) (Wegener) is a necrotizing vasculitis combining inflammation of the vascular wall and peri- and extravascular granulomatosis. Clinically, GPA is characterized in its full form by ENT signs, lung, and kidney involvement. One of the key features of GPA is the presence of ANCAs-cytoplasmic in approximately 90% of systemic forms and in 50% of localized forms-directed against proteinase 3 in most cases. PR3-ANCAs are highly specific to GPA and therefore have a high diagnostic value. Treatment of GPA is based on a combination of corticosteroids and cyclophosphamide or rituximab, which allows remission to be achieved in more than 80% of cases. Azathioprine was the most widely used maintenance treatment, but low-dose semi-annual rituximab maintenance infusions further decrease relapses with acceptable safety. Nevertheless, relapses occur in more than 50% of cases. One of the biggest treatment challenges is the occurrence of side effects, the severity and frequency of which are often linked to the prolonged treatment course, which is difficult to avoid.

Severe infections in patients with anti-neutrophil cytoplasmic antibody-associated vasculitides receiving rituximab: A meta-analysis

INTRODUCTION

The efficacy of rituximab (RTX) for remission induction and maintenance in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) is now established, but the safety, particularly concerning severe infection risk, is not well known.

OBJECTIVE

The purpose of this meta-analysis is to assess the prevalence and incidence of severe infections and the factors explaining heterogeneity in AAV patients treated with RTX.

METHODS

PubMed and Embase were searched up to December 2017. Prevalence and incidence was pooled using a random-effects model in case of significant heterogeneity (I² > 50%). Severe infection was defined as severe when it led to hospitalization, intravenous antibiotics therapy, and/or death. The heterogeneity was explored by subgroup analyses and meta-regression.

RESULTS

The included studies encompassed 1434 patients with a median age of 51.9 years. The overall prevalence and incidence of severe infections was 15.4% (95% CI [8.9; 23.3], I² = 90%, 33 studies) and 6.5 per 100 person-years (PY) (95% CI [2.9; 11.4], I² = 76%, 18 studies), respectively. The most common infections were bacterial (9.4%, 95% CI [5.1; 14.8]). The prevalence of opportunistic infection was 1.5% (95% CI [0.5; 3.1], I² = 58%) including pneumocytis jirovecii infections (0.2%, 95% CI [0.0; 0.6], I² = 0), irrespective of prophylaxis administration. Mortality related to infection was estimated at 0.7% (95% CI [0.2; 1.2], I² = 27%). The RTX cumulative dose was positively associated with prevalence of infections (13 studies, prevalence increase of 4% per 100 mg, p < .0001). The incidence of infection was negatively associated with duration of follow-up (8 studies, incidence decrease of 9% per year, p = .03).

CONCLUSION

Prevalence and incidence of severe infections, mainly bacterial ones, were high in AAV patients treated with RTX. This meta-analysis highlights the need for prospective studies to stratify infectious risk and validate cumulative RTX dose and duration of follow-up as modifying factors.

Risk factors for treatment resistance and relapse of Chinese patients with MPO-ANCA-associated vasculitis

Identification of risk factors for treatment resistance and relapse would be crucial to personalization therapy in patients with myeloperoxidase (MPO)-anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-AAV). Current evidence with regard to the risk factors for treatment resistance and relapse remains limited and inconclusive. We aimed to assess the predictors for treatment resistance and relapse in a single-center cohort of Chinese patients with MPO-AAV in this study. In total, 184 patients with MPO-AAV were included. Treatment resistance occurred in 64 (34.9%) of 184 patients and was positively associated with lung involvement (odds ratio [OR] 3.581, 95% CI 1.137-11.278, p = 0.029) and the initial serum creatinine level (OR 1.004, 95% CI 1.001-1.007, p = 0.010) and was negatively associated with platelet (OR 0.992, 95% CI 0.987-0.998, p = 0.007) and serum C3 levels (OR 0.998, 95% CI 0.996-0.999, p = 0.004). Relapse occurred in 29 (24.17%) of 120 patients in whom remission was achieved and was independently associated with lung involvement (hazard ratio [HR] 4.595, 95% CI 1.272-16.599, p = 0.020) and cardiovascular involvement (HR 3.689, 95% CI 1.237-11, p = 0.019,). The serum globulin was demonstrated to be negatively associated with relapse independently (HR 0.876; 95% CI 0.806-0.953; p = 0.002). This retrospective study of MPO-AAV patients in a single Chinese center suggests that treatment resistance was positively associated with lung involvement and the initial serum creatinine level and was negatively associated with platelet and serum C3 levels. Lung involvement and cardiovascular involvement were associated with an increased risk of relapse, while the higher serum globulin was demonstrated to be in association with a decreased risk of relapse.

Rationale of concomitant cyclophosphamide for remission-induction in patients with antineutrophil cytoplasmic antibody-associated vasculitis: A propensity score-matched analysis of two nationwide prospective cohort studies

OBJECTIVES

We evaluated the effectiveness of cyclophosphamide for patients with microscopic polyangiitis and granulomatosis with polyangiitis.

METHODS

Patients treated with cyclophosphamide and glucocorticoid (cyclophosphamide group) or glucocorticoid alone (non-cyclophosphamide group) for remission-induction were enrolled from two Japanese nationwide prospective inception cohort studies. The effectiveness and safety outcomes were compared before and after propensity score (PS)- matching.

RESULTS

Proportion of patients achieving Birmingham Vasculitis Activity Score (BVAS)-remission and BVAS-remission plus a daily prednisolone dosage of ≤10 mg (GC-remission) by Month 6 were not significantly different between cyclophosphamide and non-cyclophosphamide groups before (n = 144 and 155) and after (n = 94 for each group) PS-matching. In myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA)-positive PS-matched patients, GC-remission by Month 6 was superior in CYC group (n = 82) than in non-CYC group (n = 91) (49 vs. 31%, p = .020). Overall, end-stage renal disease-free and relapse-free survival rates, Vasculitis Damage Index score, and proportions of serious infection were comparable between the two groups both in the unmatched and PS-matched patients. Prednisolone doses at any point after treatment initiation in the PS-matched patients were lower in the cyclophosphamide group than in a non-cyclophosphamide group.

CONCLUSIONS

Concomitant cyclophosphamide use may improve GC-remission by Month 6 in MPO-ANCA-positive patients and could exert glucocorticoid sparing effect.

Smoking Is a Risk Factor for Relapse of Antimyeloperoxidase Antibodies-Associated Vasculitis

BACKGROUND/OBJECTIVE

Several studies have identified predictors of relapse in antineutrophil cytoplasmic antibody-associated small-vessel vasculitis. However, the role of smoking as a risk factor of relapse has not been elucidated. Therefore, this study aimed to evaluate whether a history of smoking is a dose-dependent independent risk factor for antineutrophil cytoplasmic antibody-associated small-vessel vasculitis relapse.

METHODS

This multicenter retrospective cohort study included 122 patients with granulomatosis with polyangiitis and microscopic polyangiitis (MPA) from 9 nephrology centers in Japan. Dose-response relationships between cigarette smoking and outcomes were assessed using multivariate Cox proportional hazards models, adjusted for clinically relevant factors. The primary outcome was the time from remission to first relapse.

RESULTS

During the observation period (median, 41 months; interquartile range, 23-66 months), 118 (95.8%) and 34 (21.7%) patients experienced at least 1 remission and 1 relapse, respectively. A log-rank test showed that smoking was significantly associated with relapse (p = 0.003). Multivariate Cox proportional hazards models found current smoking to be associated with relapse (adjusted hazard ratio, 7.48; 95% confidence interval, 2.73-21.0). An association between the risk of relapse and cumulative pack-years of smoking was also noted (p = 0.004). Smoking, however, was not associated with remission.

CONCLUSIONS

Smoking is a significant and dose-dependent risk factor for relapse of MPA. All patients with MPA who smoke should be encouraged to quit.

Molecular targeted therapies for microscopic polyangiitis and granulomatosis with polyangiitis

Clinical trials and observational studies have established cyclophosphamide (CY) or rituximab plus glucocorticoid (GC) as standard remission induction therapies in patients with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA). However, because these regimens are associated with serious adverse drug reactions, the development of drugs with novel mechanisms of actions are needed. Progress in basic and clinical research has identified novel candidate targeting molecules, including B-cell activating factor (BAF), C5a receptor, and interleukin-6. The combination of rituximab and BAF blockade in patients with MPA and GPA is under investigation in an effort to strike a better benefit-risk balance. Phase II clinical trials of avacopan (CCX168), an orally administered C5a receptor antagonist, have suggested a reduction in the dosage of concomitant GC or the replacement of GC in patients with MPA and GPA. The results from a currently ongoing phase III trial are awaited. Anecdotal case reports and an open-label pilot study have indicated the effectiveness of tocilizumab in patients with MPA and GPA. A randomized clinical trial comparing tocilizumab and intravenous CY in combination with GC is currently in progress. Molecular targeted therapy is expected to transform the treatment strategy for MPA and GPA to allow GC-free or at least less GC-dependent forms of therapy.

Understanding Long-term Remission Off Therapy in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

Introduction

In antineutrophil cytoplasmic antibody-associated (ANCA) vasculitis, relapse risk and long-term immunosuppressive therapy are problematic. Stopping immunotherapy has not been well described.

Methods

The Glomerular Disease Collaborative Network ANCA vasculitis inception cohort was evaluated. Patients who stopped all immunotherapy and those continuously on immunotherapy (≥2 years) were included. Time to first period off therapy was modeled with end-stage kidney disease and death as competing risks to understand influences of stopping therapy. Cause-specific hazard ratios (HRs) with 95% confidence intervals (CI) and P values are reported. Models controlled for age, sex, ANCA specificity, organ involvement, diagnosis era, and treatments (yes/no). Repeated events analysis was used to assess the time-dependent variable of time off treatment on recurrent relapse with HRs, 95% CIs, and P values are reported (same control variables without treatments).

Results

In 427 patients, 277 (65%) stopped therapy (median 20 months from initial induction); 14% for ≥2 different periods of time and 23% for periods ≥5 years. In multivariable models of time to discontinuation of treatment, women (HR 1.33; 95% CI 1.04-1.70; P = 0.024) and those treated with pulse methylprednisolone (HR 1.39; 95% CI 1.05-1.84; P = 0.020) were more likely to stop. The time-dependent variable of time off treatment was associated with fewer recurrent relapses (HR 0.51; 95% CI 0.41-0.63; P < 0.001).

Conclusions

Stopping immunotherapy was common. Women and those treated with methylprednisolone stop treatment more often, but underlying mechanisms are unknown. Stopping treatment was associated with fewer relapses, suggesting that even without guidelines there may be benefits without an untoward detriment of relapse.

Systematic review and meta-analysis for 2017 clinical practice guidelines of the Japan research committee of the ministry of health, labour, and welfare for intractable vasculitis for the management of ANCA-associated vasculitis

OBJECTIVES

To provide evidence for the revision of clinical practice guideline (CPG) for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) by the Japan Research Committee for Intractable Vasculitis.

METHODS

PubMed, CENTRAL, and the Japan Medical Abstracts Society were searched for articles published between January 1994 and January 2015 to conduct systematic review (SR), and the quality of evidence was assessed with GRADE approach.

RESULTS

Nine randomized controlled trials (RCTs) and two non-RCTs were adopted for remission induction therapy, three RCTs and two non-RCTs for plasma exchange, and five RCTs and one non-RCT for remission maintenance therapy. A significant difference was found in efficacy and safety for the following comparisons. In the non-RCT adopted for remission induction therapy, glucocorticoid (GC) + cyclophosphamide (CY) was significantly superior to GC monotherapy regarding remission. GC + intravenous CY for remission induction therapy was superior to GC + oral CY regarding death at one year, serious adverse events, and serious infection. Concomitant use of plasma exchange for remission induction therapy of AAV with severe renal dysfunction reduced risk of end-stage renal disease versus non-users at month 3.

CONCLUSION

This SR provided necessary evidence for developing CPG for the management of ANCA-associated vasculitis.

2017 Clinical practice guidelines of the Japan Research Committee of the Ministry of Health, Labour, and Welfare for Intractable Vasculitis for the management of ANCA-associated vasculitis

OBJECTIVE

The Japan Research Committee for Intractable Vasculitis has fully revised the clinical practice guidelines (CPG) for the management of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) to improve and standardize the medical treatment of the disease in Japan.

METHODS

The previous CPG was published in a classical review style in Japanese in 2011 and 2014. We adopted the Grading of Recommendations Assessment, Development and Evaluation system for this revision, and various stakeholders, including patients, participated in it. The expected users of this CPG are AAV patients in Japan and their families and healthcare professionals, including both AAV specialists and non-specialists. We set clinical questions concerning the three important clinical topics of remission induction therapy, plasma exchange, remission maintenance therapy, and developed eight recommendation statements.

RESULTS

For remission induction therapy for newly developed AAV, we weakly recommend glucocorticoid (GC) plus intravenous cyclophosphamide pulse (IVCY) or oral cyclophosphamide (POCY) rather than GC alone, and IVCY rather than POCY. We also weakly recommend CY rather than rituximab. In the case of AAV with severe renal impairment, we weakly recommend plasma exchange as a conjunction therapy. We weakly recommend azathioprine for remission maintenance therapy.

CONCLUSION

The revised CPG has demonstrated evidence-based treatment recommendations for AAV.

Urinary epidermal growth factor predicts renal prognosis in antineutrophil cytoplasmic antibody-associated vasculitis

INTRODUCTION

The current study aimed to investigate the association between urinary epidermal growth factor (uEGF) and renal disease severity and outcomes in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV).

METHODS

Intrarenal EGFmRNA expression was extracted from transcriptomic data of microdissected tubulointerstitial compartments of kidney biopsies of patients with AAV. uEGF was measured in 173 patients with AAV in active stage and 143 in remission, and normalised to urine creatinine excretion (uEGF/Cr). The association between uEGF/Cr (or EGFmRNA) and clinical-pathological parameters was tested using linear regression analysis. The ability of uEGF/Cr to predict renal outcomes was analysed using Cox's regression analysis.

RESULTS

In patients with AAV, intrarenal EGFmRNA expression was significantly associated with estimated glomerular filtration rate (eGFR)(log2) at time of biopsy (β=0.63, p<0.001). The level of uEGF/Cr was significantly higher in patients in remission than in patients with active disease, both when looking at patients with sequential measurements (2.75±1.03vs 2.08±0.98, p<0.001) and in cross-sectional comparison. uEGF/Cr level was positively associated with eGFR(log2) at time of sampling in both active and remission stage (β=0.60, p<0.001; β=0.74, p<0.001, respectively). Patients with resistant renal disease had significantly lower uEGF/Cr levels than responders (1.65±1.22vs 2.16±1.26, p=0.04). Moreover, after adjusting for other potential predictors, uEGF/Cr was independently associated with composite endpoint of end-stage renal disease or 30% reduction of eGFR (HR 0.61, 95% CI 0.45 to 0.83, p=0.001).

CONCLUSION

Lower uEGF/Cr levels are associated with more severe renal disease, renal resistance to treatment and higher risk of progression to composite outcome in patients with AAV.

Granulomatosis with polyangiitis in Northeastern Brazil: study of 25 cases and review of the literature

BACKGROUND

Little has been published about the epidemiology of Granulomatosis with polyangiitis (GPA) in South America, especially in the intertropical zone, and no epidemiological data from Brazil are available. The purpose of the present study was to draw a clinical and demographic profile of GPA patients living in Northeastern Brazil based on laboratory, histological and imaging findings, and evaluate the frequency of organic involvement.

METHODS

Clinical, epidemiological and treatment data of GPA patients were collected retrospectively and compared with the literature.

RESULTS

The cohort included 25 GPA patients (84% female) aged 45.8 ± 16.1 years. Renal and ear-nose-throat (ENT) manifestations were the most common (both 64%). One third (32%) of the patients had 24-h proteinuria > 1 g, 50% had creatinine clearance < 50 mL/min at the time of diagnosis, and 33% had recurrent kidney damage during disease progress. The affected organs included lungs (60%), joints (44%), skin (32%), peripheral nervous system (28%), eyes (28%) and heart (16%). ENT involvement (n = 16/64%) was less frequent in our region than in São Paulo (n = 115/85.8%). Renal (n = 16/64%) and pulmonary (n = 15/60%) involvement was less frequent in our region than in the U.K. (renal n = 30/90%; pulmonary n = 28/84.8%).

CONCLUSION

Most of our patients were female, presented the generalized form and were diagnosed late. The frequency of the main clinical manifestations (ENT, renal and pulmonary) was lower than that observed at higher latitudes, suggesting the existence of a Northeast Brazilian clinical and epidemiological profile and adding to our knowledge of this rare condition.

Myeloperoxidase-ANCA-positive granulomatosis with polyangiitis is a distinct subset of ANCA-associated vasculitis: A retrospective analysis of 455 patients from a single center in China

OBJECTIVE

Antineutrophil cytoplasmic antibody (ANCA) directed to proteinase 3 (PR3) used to be considered the serologic marker for granulomatosis with polyangiitis (GPA). However, patients with myeloperoxidase (MPO)-ANCA positive GPA have been increasingly reported. The aim of this study was to analyze the clinical and pathological characteristics and outcome of Chinese patients with MPO-ANCA positive GPA.

METHODS

The clinical and renal histology data, renal outcomes, response to treatment, relapse and mortality were compared between patients with MPO-ANCA positive GPA and MPO-ANCA positive microscopic polyangiitis (MPA) as well as proteinase 3 (PR3)-ANCA positive GPA.

RESULTS

455 patients with ANCA-associated vasculitis (AAV) were recruited in this study. 276/455 patients were classified as MPO-ANCA positive MPA, 4/455 patients were classified as PR3-ANCA positive MPA, 124/455 were MPO-ANCA positive GPA and 51/455 were PR3-ANCA positive GPA. Compared with MPO-ANCA positive MPA patients, MPO-ANCA positive GPA patients had significantly higher level of BVAS and milder renal lesion at diagnosis. The probability of developing ESRD was significantly higher in patients with MPO-ANCA positive MPA than MPO-ANCA positive GPA. MPO-ANCA positive GPA patients were likely to have relapse than MPO-ANCA positive MPA patients. Compared with PR3-ANCA positive GPA patients, MPO-ANCA positive GPA patients had significantly higher proportion of female, less constitutional symptoms and milder renal lesion at diagnosis.

CONCLUSIONS

Patients with MPO-ANCA positive GPA should be regarded as a unique subset of AAV. This subset of AAV patients had relatively milder renal injury. Although ANCA specificities play an important role in differentiating AAV, taking the disease type together to classify AAV may be more rational.

Prognostic Significance of Cavitary Lung Nodules in Granulomatosis With Polyangiitis (Wegener's): A Clinical Imaging Study of 225 Patients

OBJECTIVE

Granulomatosis with polyangiitis (Wegener's) (GPA) is a systemic necrotizing vasculitis in which pulmonary nodules are a common manifestation. Our study examined whether pulmonary nodules, and nodule type (solid versus cavitary), are associated with different disease manifestations and outcomes.

METHODS

Demographic, clinical, biologic, and radiologic data at diagnosis and during followup and treatments of GPA patients followed at the Mount Sinai Hospital (Canada) Vasculitis Clinic were analyzed. Patients were separated by the absence of lung nodules, presence of solid nodules only, and presence of cavitary nodules (+/- solid nodules). The study outcomes included followup lung imaging, relapses, and deaths.

RESULTS

Of 225 patients with GPA, 46 had solid nodules only and 44 had cavitary nodules at diagnosis. Demographic and clinical manifestations were similar in the patient subgroups at diagnosis. Cyclophosphamide (CYC) was used for induction after diagnosis in 76.7% of patients with cavitary nodules, compared with 64.7% of patients without nodules and 51.1% of patients with solid nodules (P = 0.04). The mean ± SD followup after diagnosis was 106.6 ± 92.6 months, and 6 of the patients died. In multivariable analysis, diagnosis before 2000 or pulmonary nodule cavitation at diagnosis were associated with relapse, with a hazard ratio of 0.38 (95% confidence interval [95% CI] 0.22-0.65; P < 0.001) and 1.53 (95% CI 1.00-2.33; P = 0.05), respectively, after adjustment for CYC use.

CONCLUSION

The presence of cavitary nodules led to increased use of CYC but had no impact on survival. Relapse occurred more often, however, in patients with cavitary nodules than in those with solid nodules or no nodules, and should be studied in other cohorts.

Patient Outcomes in Renal-Limited Antineutrophil Cytoplasmic Antibody Vasculitis With Inactive Histology

Introduction

Little is known about the anticipated disease course for individuals who present with renal-limited antineutrophil cytoplasmic antibody (ANCA)−associated vasculitis but who lack inflammation on a kidney biopsy. The impact of immunosuppression on renal and overall survival is unknown.

Methods

Patients were recruited from 2005 to 2016 from 8 centers worldwide (N = 16) for this descriptive study. All had positive ANCA, elevated serum creatinine with active urine sediment, histologic evidence of pauci-immune glomerulonephritis without active lesions, and had no evidence of extrarenal vasculitis. We describe the characteristics of this cohort and the differences in the clinical, histologic, and therapeutic parameters of those who developed primary outcomes of end-stage renal disease (ESRD) and vasculitis relapse.

Results

The cohort was 63% Caucasian, and 75% were men, with a median age of 62 years. At entry, the mean ± SD estimated glomerular filtration rate (eGFR) was 24 ± 20 ml/min per 1.73 m², and 5 patients required dialysis. Twelve patients received immunosuppressive therapy, 25% experienced disease relapse, and 38% developed ESRD. Patients who developed ESRD had lower baseline eGFRs (8 ± 5 ml/min per 1.73 m² vs. 35 ± 18 ml/min per 1.73 m²; P = 0.001) and more often required dialysis at presentation (83% vs. 0%; P = 0.001). Patients who relapsed were less likely to receive immunosuppression (25% for the relapsed group vs. 92% for the nonrelapsed group; relative risk: 0.27, risk difference: 67%; P = 0.03).

Conclusion

Among these patients, lower initial eGFR and dialysis dependence at presentation might increase the risk for ESRD. Immunosuppression did not affect renal outcomes in this sample of patients but was associated with a reduced risk for vasculitis relapse. More information is needed on factors that predict treatment response in this high-risk group.

Paediatric anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis: an update on renal management

The anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are a group of disorders characterized by necrotizing inflammation of the small to medium vessels in association with autoantibodies against the cytoplasmic region of the neutrophil. Included in this definition are granulomatosis with polyangiitis (GPA, formerly known as Wegener's granulomatosis), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (formerly known as Churg-Strauss syndrome). AAV are chronic, often relapsing diseases that can be organ or life threatening. Despite immunosuppression, the morbidity and mortality remain high. Renal involvement contributes significantly to the morbidity with high numbers of patients progressing to end-stage kidney disease. Current therapies have enabled improvements in renal function in the short term, but evidence for long-term protection is lacking. In MPA, renal involvement is common at presentation (90%) and often follows a more severe course than that seen in paediatric GPA. Renal biopsy remains the 'gold standard' in diagnosing ANCA-associated glomerulonephritis. While GPA and MPA are considered separate entities, the two are managed identically. Current treatment regimens are extrapolated from adult studies, although it is encouraging to see recruitment of paediatric patients to recent vasculitis trials. Traditionally more severe disease has been managed with the 'gold standard' treatment of glucocorticoids and cyclophosphamide, with remission rates achieved of between 70 and 100%. Other agents employed in remission induction include anti-tumor necrosis factor-alpha therapy and mycophenolate mofetil. Recently, however, increasing consideration is being given to rituximab as a therapy for children in severe or relapsing disease, particularly for those at risk for glucocorticoid or cyclophosphamide toxicity. Removal of circulating ANCA through plasma exchange is a short-term measure reserved for severe or refractory disease. Maintenance therapy usually involves azathioprine. The aim of this article is to provide a comprehensive review of paediatric AAV, with a focus on renal manifestations, and to highlight the recent advances made in therapeutic management.

Persistent hematuria in patients with antineutrophil cytoplasmic antibody-associated vasculitis during clinical remission: chronic glomerular lesion or low-grade active renal vasculitis?

Background

Whether persistent hematuria in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) during clinical remission reflects active disease or chronic glomerular injury is uncertain. This study aimed to investigate the significance of persistent hematuria during clinical remission in a large cohort of AAV patients.

Methods

A cohort of 219 AAV patients in complete clinical remission after induction therapy at our center was retrospectively studied, and their clinical and laboratory data as well as long-term outcomes were analyzed.

Results

A total of 80 out of 219 patients had persistent hematuria during clinical remission of AAV. Compared with patients without hematuria during remission, the slope of eGFR decline in patients with persistent hematuria was significantly higher during the long-term follow-up [3.6 (IQR 1.2, 7.2) vs. 1.5 (IQR 0.2, 4.0) mL/min/1.73 m²/year, P < 0.001]. Among the 80 patients with persistent hematuria during remission, there was little difference between those with fast and slow decline of eGFR, as divided by either median or interquartile range of the slope of eGFR decline. We also compared patients without hematuria who had a slope of eGFR decline that was lower than the median level of the slope of eGFR decline with those with persistent hematuria, and found that patients with hematuria had significantly lower levels of CRP and ESR at baseline and higher levels of ANCA at remission.

Conclusions

Among the AAV patients who achieved clinical remission after immunosuppressive therapy, those with persistent hematuria are not rare and may reflect either chronic renal damage or low-grade active renal disease.

Trends in Long-Term Outcomes Among Patients With Antineutrophil Cytoplasmic Antibody-Associated Vasculitis With Renal Disease

OBJECTIVE

It is still not clear how advances in the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) have impacted long-term outcomes. We undertook this study to examine changes over 25 years in long-term clinical outcomes, including the impact of renal function at diagnosis (a potential marker of time to disease detection) and the duration of cyclophosphamide use in AAV patients with renal involvement.

METHODS

We included ANCA-positive patients with biopsy-proven AAV diagnosed between 1985 and 2009 who were followed up in the Glomerular Disease Collaborative Network inception cohort. Outcomes included the composite outcome of end-stage renal disease (ESRD) or death as well as relapse. Cox proportional hazards or competing risks regression models were adjusted for potential baseline confounders.

RESULTS

Data from 554 patients were included in the analysis. There was a decreasing 5-year risk of ESRD or death over time (P < 0.001 by log rank test for trend). After adjustment for baseline characteristics, the risk of relapse was similar across the time periods (P = 0.45 by test for trend). Serum creatinine level at baseline was the only significant predictor of an increased risk of ESRD or death (hazard ratio 1.11 per 1 mg/dl of serum creatinine [95% confidence interval 1.04-1.18], P = 0.002).

CONCLUSION

In patients with renal disease secondary to AAV, over 25 years the risk of ESRD or death has decreased but the risk of relapse has not changed. A higher serum creatinine level at diagnosis is associated with a higher risk of ESRD or death, suggesting that earlier disease detection is potentially an important measure to improve outcomes in AAV.

A tale of two vasculitides: biopsy-proven giant cell arteritis followed by the independent development of renal-limited microscopic polyangiitis

We describe an 80-year-old woman who presented with headaches, bilateral jaw claudication and visual symptoms. She was diagnosed with giant cell arteritis, which was confirmed by temporal artery biopsy. She was treated with high-dose prednisone followed by a slow taper, with complete resolution of symptoms. Approximately 4 years later, she developed progressively worsening renal function associated with haematuria. Serological workup revealed a high-titre perinuclear antinuclear cytoplasmic antibody and antibodies to myeloperoxidase. Renal biopsy demonstrated a pauci-immune focal crescentic glomerulonephritis. Extensive review of systems, physical exam and diagnostic studies demonstrated no evidence of extra-renal disease, and she was diagnosed with renal-limited microscopic polyangiitis. High-dose prednisone was resumed, but she refused treatment with either cyclophosphamide or rituximab due to concern for toxicity. Her prednisone dose was tapered and renal function stabilised. Our case highlights the need to recognise the successive occurrence of two distinct vasculitides in a single patient and monitor accordingly.

ANCA-Associated Glomerulonephritis: Risk Factors for Renal Relapse

Relapse in ANCA-associated vasculitis (AAV) has been studied previously, but there are few studies on renal relapse in particular. Identifying patients at high risk of renal relapse may aid in optimizing clinical management. We investigated which clinical and histological parameters are risk factors for renal relapse in ANCA-associated glomerulonephritis (AAGN). Patients (n = 174) were newly diagnosed and had mild–moderate or severe renal involvement. Data were derived from two trials of the European Vasculitis Society: MEPEX and CYCAZAREM. The Cox regression model was used to identify parameters increasing the instantaneous risk (= rate) of renal relapse (useful for instant clinical decisions). For identifying predictors of renal relapse during follow-up, we used Fine & Gray’s regression model. Competing events were end-stage renal failure and death. The cumulative incidence of renal relapse at 5 years was 9.5% (95% CI: 4.8–14.3%). In the Cox model, sclerotic class AAGN increased the instantaneous risk of renal relapse. In Fine & Gray’s model, the absence of interstitial infiltrates at diagnosis was predictive for renal relapse. In this study we used two different models to identify possible relationships between clinical and histopathological parameters at time of diagnosis of AAV with the risk of experiencing renal relapse. Sclerotic class AAGN increased the instantaneous risk of renal relapse. This association is most likely due to the high proportion of sclerosed glomeruli reducing the compensatory capacity. The absence of interstitial infiltrates increased the risk of renal relapse which is a warning sign that patients with a relatively benign onset of disease may also be prone to renal relapse. Renal relapses occurring in patients with sclerotic class AAGN and renal relapses occurring in patients without interstitial infiltrates were mutually exclusive, which may indicate that they are essentially different.

The prognostic significance of the Birmingham Vasculitis Activity Score (BVAS) with systemic vasculitis patients transferred to the intensive care unit (ICU)

Systemic vasculitides represent a heterogeneous group of diseases that share clinical features including respiratory distress, renal dysfunction, and neurologic disorders. These diseases may often cause life-threatening complications requiring admission to an intensive care unit (ICU). The aim of the study was to evaluate the validity and responsiveness of Birmingham Vasculitis Activity Score (BVAS) score to predict survival in patients with systemic vasculitides admitted to ICU.A retrospective study was carried out from 2004 to 2014 in 18 patients with systemic vasculitis admitted to 2 different Rheumatology divisions and transferred to ICU due to clinical worsening, with a length of stay beyond 24 hours. We found that ICU mortality was significantly associated with higher BVAS scores performed in the ward (P = 0.01) and at the admission in ICU (P = 0.01), regardless of the value of Acute Physiology And Chronic Health Evaluation (APACHE II) scores (P = 0.50). We used receiver-operator characteristic (ROC) curve analysis to evaluate the possible cutoff value for the BVAS in the ward and in ICU and we found that a BVAS > 8 in the ward and that a BVAS > 10 in ICU might be a useful tool to predict in-ICU mortality.BVAS appears to be an excellent tool for assessing ICU mortality risk of systemic vasculitides patients admitted to specialty departments. Our experience has shown that performing the assessment at admission to the ward is more important than determining the evaluation before the clinical aggravation causing the transfer to ICU.

Simultaneous comprehensive multiplex autoantibody analysis for rapidly progressive glomerulonephritis

Rapidly progressive glomerulonephritis (RPGN) is mainly caused by anti-glomerular basement membrane (GBM) antibody-mediated glomerulonephritis, immune-complex or anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides and leads to rapid loss of renal function. Detection of ANCA and autoantibodies (autoAbs) to GBM and dsDNA enables early diagnosis and appropriate treatment of RPGN aiding in preventing end-stage renal disease.Determination of ANCA on neutrophils (ANCA) as well as autoAbs to myeloperoxidase (MPO-ANCA), proteinase 3 (PR3-ANCA), GBM, and dsDNA was performed by the novel multiplex CytoBead technology combining cell- and microbead-based autoAb analyses by automated indirect immunofluorescence (IIF). Forty patients with granulomatosis with polyangiitis (GPA), 48 with microscopic polyangiitis (MPA), 2 with eosinophilic GPA, 42 with systemic lupus erythematosus (SLE), 43 with Goodpasture syndrome (GPS), 57 with infectious diseases (INF), and 55 healthy subjects (HS) were analyzed and findings compared with classical single testing.The CytoBead assay revealed for GPA, MPA, GPS, and SLE the following diagnostic sensitivities and for HS and INF the corresponding specificities: PR3-ANCA, 85.0% and 100.0%; MPO-ANCA, 77.1% and 99.1%; anti-GBM autoAb, 88.4% and 96.4%; anti-dsDNA autoAb, 83.3% and 97.3%; ANCA, 91.1% and 99.1%, respectively. Agreement with classical enzyme-linked immunosorbent assay and IIF was very good for anti-GBM autoAb, MPO-ANCA, PR3-ANCA, and ANCA, respectively. Anti-dsDNA autoAb comparative analysis demonstrated fair agreement only and a significant difference (P = 0.0001).The CytoBead technology provides a unique multiplex reaction environment for simultaneous RPGN-specific autoAb testing. CytoBead RPGN assay is a promising alternative to time-consuming single parameter analysis and, thus, is well suited for emergency situations.

Beneficial Effect of Gabexate Mesilate on Microscopic Polyangiitis With Renal Dysfunction and Pulmonary Hemorrhage

Corticosteroids and cyclophosphamide are the mainstay of the treatment of microscopic polyangiitis involving pulmonary hemorrhage or rapidly progressive glomerulonephritis. However, patients with advanced age are unable to tolerate this combined therapy, because of a relatively high incidence of side effects including infection, hemorrhagic cystitis, and bone marrow suppression. The authors encountered an 80-year-old patient with pulmonary hemorrhage and renal dysfunction ascribed to microscopic polyangiitis and achieved successful treatment by employing gabexate mesilate in addition to corticosteroids. The present case suggests that gabexate mesilate may be a therapeutic option for microscopic polyangiitis with progressive renal failure and pulmonary hemorrhage.

Difference in relapse-rate and clinical phenotype by autoantibody-subtype in Japanese patients with anti-neutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

To correlate the serotype specificity to myeloperoxidase (MPO) and proteinase-3 (PR3) with clinical characteristics in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

Clinical characteristics and outcomes of patients with AAV in our division from 2005 to 2014 were retrospectively compared on the basis of ANCA subtype.

RESULTS

We collected the data from 88 patients with MPO-ANCA vasculitis, and 17 with PR3-ANCA vasculitis. Patients with PR3-ANCA vasculitis were younger, and had higher involvement-rates in the eye, nose, and ear. In both MPO- and PR3-ANCA vasculitis, the most frequently involved organ was the respiratory system. Interstitial pneumonia was more frequent in MPO-ANCA vasculitis (52.3% versus 5.9%, p < 0.01), whereas nodular shadow was more frequent in PR3-ANCA vasculitis (9.1% versus 58.8%, p < 0.01). Multivariable Cox proportional hazard regression analysis showed that the hazard ratio of PR3-ANCA for relapse was 2.48 (95% confidence interval 1.14-5.42, p = 0.02). There was no difference in the survival and the progression to end-stage kidney disease and respiratory failure between the two vasculitides.

CONCLUSION

MPO-ANCA vasculitis was a predominant form of AAV in Japan. Classification based on ANCA subtype would be clinically relevant in the prediction of organ involvement and relapse.

Podocyte Detachment Is Associated with Renal Prognosis in ANCA-Associated Glomerulonephritis: A Retrospective Cohort Study

The prognosis of antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis (ANCA-GN) is unfavorable despite immunosuppressive therapy. It has been suggested that the loss of podocytes is a hallmark of progressive kidney disease. However, it is unclear about podocyte injuries and their predictive values on the prognosis in ANCA-GN. Therefore, the current study aimed to investigate the podocyte injury in renal histopathology and its association with renal prognosis of patients with ANCA-GN. A total of 170 patients with ANCA-GN were recruited in this study. Morphometric investigation of podocytes by electron microscopy including foot process width (FPW), podocyte density per glomerulus (Nv), and glomerular basement membrane (GBM) width were measured and calculated in ANCA-GN patients. Cox regression analysis was used to analyze the association between podocyte injuries and prognosis of patients with ANCA-GN. Foot processes broadening, podocyte detachment, and GBM thickening could be observed in electron micrographs in the specimens of 158/170 (92.9%), 142/170 (83.5%), and 150/170 (88.2%) patients, respectively. Compared with normal controls, FPW and GBM width in ANCA-GN patients was significantly higher (1269.39 ± 680.19 vs 585.81 ± 77.16, P = 0.004; 668.23 ± 208.73 vs 354.23 ± 52.70, P = 0.000, respectively), while the podocyte density was significantly lower (55.90 ± 36.32 vs 255.23 ± 47.29, P = 0.000). The podocyte density was independently associated with the recovery of renal function in logistic regression analysis (OR, 1.083; 95% CI, 1.025-1.440; P = 0.005). Furthermore, multivariate analysis revealed that podocyte density was an independent predictor of end-stage renal disease (ESRD) (model A: HR, 0.950; 95% CI, 0.919-1.982; P = 0.002; model B: HR, 0.953; 95% CI, 0.922-0.985; P = 0.004). Podocyte structural damage and detachment occurred frequently in patients with ANCA-GN. Moreover, podocyte detachment was an independent predictor of renal outcomes.

Recovery of renal function after glucocorticoid therapy for IgG4-related kidney disease with renal dysfunction

BACKGROUND

Although renal dysfunction in IgG4-related kidney disease (IgG4-RKD) shows rapid resolution with glucocorticoid therapy, little is known about the appropriate initial glucocorticoid dose for induction therapy or long-term renal outcome.

METHODS

We retrospectively examined the differences in recovery of renal function according to the dose of glucocorticoid used for induction therapy and the long-term renal outcome in 43 patients with definite IgG4-RKD (mostly IgG4-tubulointerstitial nephritis), in whom the estimated glomerular filtration rate (eGFR) before glucocorticoid therapy was <60 ml/min.

RESULTS

Most patients were treated with glucocorticoid alone and had been maintained on glucocorticoid. The initial dose of prednisolone employed was ≤0.6 mg/kg/day (mean 0.47) in 27 patients (group L), and >0.6 mg/kg/day (mean 0.81) in 16 patients (group H). In both groups, the pretreatment eGFR was significantly improved at 1 month after the start of glucocorticoid therapy and the degree of improvement showed no significant inter-group difference. Relapse of IgG4-RKD occurred in 16.7% of the group L patients and 13.3% of the group H patients (p = 0.78). Among 29 patients who were followed up for over 36 months (mean 74 months) and had been maintained on glucocorticoid, none showed progression to end-stage renal disease and there was no significant difference between eGFR at 1 month after treatment and eGFR at the last review.

CONCLUSION

In glucocorticoid monotherapy for IgG4-RKD, a moderate dose is sufficient for induction, and recovery of renal function can be maintained for a long period on low-dose maintenance, although relapse can occur even in patients receiving maintenance therapy.