Characteristics of MPO-ANCA-positive granulomatosis with polyangiitis: a retrospective multi-center study in Japan

Relapse Predictors in Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) are a group of rare diseases with a chronic and relapsing course. Recent treatment guidelines offer many therapeutic options depending mainly on the type of diagnosis and disease manifestations. Areas that remain under discussion include whether all patients diagnosed with AAV belong to a homogeneous group with a similar prognosis at baseline or if the type and duration of remission-inducing treatment should depend on factors other than just diagnosis and disease severity. The aim of this review is to present the recent literature on the tools available to use while evaluating the risk of relapse in patients upon presentation as well as potential biomarkers of proceeding flare in patients upon remission.

Sinonasal manifestations of granulomatosis with polyangiitis: A retrospective analysis

OBJECTIVE

This study aimed to examine the characteristics of nasal and imaging findings of sinonasal lesions in granulomatosis with polyangiitis (GPA) patients and how these lesions change over time in both the active and remission phases of the disease.

METHODS

We retrospectively reviewed GPA patients with sinonasal lesions who were followed up at our department between January 2005 and December 2020. The following data were collected: age, sex, symptoms at initial presentation, anti-neutrophil cytoplasmic antibody (ANCA) type, and histopathological, nasal (initial and follow-up), and imaging (initial and follow-up) findings.

RESULTS

This study included 17 patients with GPA aged 30 to 79 years. Computed tomography (CT) of the sinuses showed mucosal thickening in 16 patients, bone thickening in 12, bone destruction in 4, and an orbital invasion mass in 3 at the time of diagnosis. After initiating treatment, mucosal thickening of the sinuses improved in 3 of 16 patients and remained unchanged in 13. Bone thickening at the time of diagnosis remained unchanged in 10 of 12 patients and worsened in 2; 1 patient displayed newly developed bone thickening. Destructive nasal findings on CT were positive for proteinase 3-ANCA.

CONCLUSIONS

Our study revealed that mucosal thickening, bone thickening, bone destruction, and orbital invasion mass were major CT findings in patients with GPA. Intranasal findings such as granulations, crusting, and necrosis were seen in the active phase; moreover, saddle nose, loss of turbinate, and nasal septal perforation were subsequently seen in the course of the disease. Sinonasal findings of GPA vary depending on the disease stage and period.

Aural Manifestations of Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis-Diagnosis, Symptoms, Treatment

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of vasculitis sharing a common pathophysiology, which affects small and medium blood vessels. There are three categories of AAV: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). As a systemic disease, AAV can affect basically every organ. The goal of this publication is to sum up and underline the problem of the aural manifestation of AAV; it details the definition of Otitis Media with Antineutrophil Cytoplasmic Antibody Associated Vasculitis (OMAAV) and allows for a better understanding of the specific tasks of medical professionals taking part in the diagnostic and therapeutic process. Among others, this publication is directed to otolaryngologists who may encounter patients with AAV and often are the first specialists who see patients with early symptoms of AAV. This publication presents brief characteristics of AAV, descriptions of aural manifestations and symptoms, differential diagnosis, and both pharmacological and surgical treatment options, based on current recommendations and information found in the literature and clinical databases.

The Diagnosis of Granulomatosis With Polyangiitis When Serology and Biopsies are Negative

Objective

Granulomatosis with polyangiitis (GPA) is a potentially fatal condition which often manifests in the head and neck. Currently, diagnosis relies on antineutrophil cytoplasmic autoantibody (c-ANCA) serology and mucosal or renal biopsy. However, a significant proportion of patients with GPA limited to the head and neck are seronegative and biopsy negative. This study evaluates the role of clinical diagnosis of GPA in the absence of positive laboratory findings.

Study Design

Case series with chart review.

Setting

Academic Tertiary Medical Center.

Methods

This was a retrospective review of 143 patients treated in an outpatient otolaryngology clinic at a tertiary care hospital for known or suspected GPA from 1998 to 2021. Presenting symptoms, C-ANCA status at initial presentation, biopsy results, long-term serology results, and time to initiation of treatment were analyzed.

Results

Twenty-six of 143 (18.2%) patients were seronegative; only 3 of these patients (12%) had positive biopsies. Seventeen (73.9%) of these patients presented with nasal and sinus disease and 12 (52.2%) presented with airway involvement. Only 4 (17.4%) patients had renal involvement. Delay in treatment of patients with negative laboratory workup ranged from 0 months to 11 years. All patients who were seronegative and/or biopsy negative at presentation responded clinically to immunosuppressive therapy.

Conclusion

GPA cases are often limited to the upper respiratory tract, making diagnosis difficult, particularly in seronegative patients. These results suggest that, when GPA is suspected, despite negative serology, the diagnosis of GPA should be made on clinical grounds, and empiric therapy encouraged to prevent delay in treatment.

Differences in the epidemiology, management and outcomes of kidney disease in men and women

Improved understanding of differences in kidney disease epidemiology, management and outcomes in men and women could help nephrologists to better meet the needs of their patients from a sex- and gender-specific perspective. Evidence of sex differences in the risk and outcomes of acute kidney injury is mixed and dependent on aetiology. Women have a higher prevalence of chronic kidney disease (CKD) stages 3-5 than men, whereas men have a higher prevalence of albuminuria and hence CKD stages 1-2. Men show a faster decline in kidney function, progress more frequently to kidney failure and have higher mortality and risk of cardiovascular disease than women. However, the protective effect of female sex is reduced with CKD progression. Women are less likely than men to be aware of, screened for and diagnosed with CKD, started on antiproteinuric medication and referred to nephrologist care. They also consistently report a poorer health-related quality of life and a higher symptom burden than men. Women experience greater barriers than men to access the waiting list for kidney transplantation, particularly with respect to older age and obesity. However, women also have longer survival than men after transplantation, which may partly explain the comparable prevalence of transplantation between the sexes.

Recent advances in the treatment strategy for AAV improved outcomes with intensive GC tapering

OBJECTIVE

To evaluate trends in results of care and management for antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV).

METHODS

We employed multicenter cohort data collected during 2011-2021, recruiting 43 patients with granulomatosis with polyangiitis (GPA) and 91 with microscopic polyangiitis (MPA). According to the median registration date of September 2015, patients have split into two groups: an early group and a late group (both of them, n = 67). To prevent bias, a propensity score according to numerous baseline characteristics variables was calculated; 50 matching members of each group were statistically extracted. Their treatments and clinical outcomes were examined at 6, 12, and 24 months after initial remission therapy.

RESULTS

Statistics demonstrated that the baseline characteristics were similar. The late group used rituximab (RTX) more often for both remission induction and maintenance therapy, compared with the early group. The mean daily PSL doses of the late group were significantly lower than those of early group at each time point. The late group discontinued PSL 14.0% at 12 months and 23.3% at 24 months. Despite their intensive glucocorticoids (GC) tapering, the remission rates and the relapse rates were significantly fairer in the late group. The Vasculitis Damage Index (VDI) and VDI due to GC at each time point were lower in the late group, and those differences had become wider over time.

CONCLUSION

Recent developments in AAV treatment have allowed efficient remission and prevention of relapses, which in turn enabled extensive GC tapering causing fewer sequelae.

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.

Myeloperoxidase-antineutrophil cytoplasmic antibody-associated vasculitis with headache and kidney involvement at presentation and with arthralgia at relapse: A case report

BACKGROUND

Patients with proteinase 3-antineutrophil cytoplasmic antibody associated vasculitis (AAV) experience different manifestations at the initial onset and relapse. However, such cases of different initial and relapse manifestations have not been reported in myeloperoxidase (MPO)-AAV patients.

CASE SUMMARY

A 52-year-old woman was admitted to our hospital because of headache. Laboratory findings indicated nephrotic range proteinuria and microscopic hematuria, serum creatinine of 243 μmol/L, anti-MPO antibody titer of > 400 RU/mL, and positive perinuclearantineutrophil cytoplasmic antibody. Renal biopsy showed pauci-immune crescentic glomerulonephritis. The cerebrospinal fluid examination and brain magnetic resonance imaging did not show any abnormality. Therefore, MPO-AAV was diagnosed. Corticosteroids, plasmapheresis, and cyclophosphamide as induction therapy and mycophenolate mofetil (MMF) as maintenance therapy were administered. The patient's headache disappeared; serum creatinine returned to normal; complete remission of microscopic hematuria and proteinuria was observed. Anti-MPO antibody titer reached normal limits after immunosuppressive treatment. Twenty-five months after stopping the immunosuppressive treatment, the patient relapsed with arthralgia, without neurological or renal involvement. The patient's arthralgia improved after treatment with prednisone and MMF.

CONCLUSION

We have reported a rare case of MPO-AAV who initially presented with headache and kidney involvement. However, relapse presented with only arthralgia, which was completely different from the initial manifestations. This case suggests that AAV relapse should be highly suspected in MPO-AAV patients after remission, when clinical manifestations at relapse are different from those at onset. Prednisone and MMF may provide a good choice for refractory arthralgia during relapse in MPO-AAV patients.

Ophthalmic manifestations and visual outcomes of granulomatosis with polyangiitis: a retrospective multicentre study in Korea

OBJECTIVES

To analyse the ophthalmic manifestations and treatment outcomes of Korean patients with granulomatosis with polyangiitis (GPA).

METHODS

One hundred twenty patients diagnosed with GPA by rheumatologists from January 1984 to March 2019 at three referral centres were retrospectively reviewed. Patients with ophthalmic symptoms were examined by ophthalmologists and underwent orbital imaging. Ophthalmic manifestations were divided into ocular involvement and ocular adnexal involvement. Multivariable logistic regression was used to examine the factors related to ocular, ocular adnexal, and optic nerve involvement. Visual improvement was defined as a best-corrected visual acuity gain of ≥2 Snellen lines, accompanied by improvements in optic nerve function.

RESULTS

Ophthalmic manifestations were observed in 50 patients (41.7%) during the median follow-up period of 6.7 years. Proteinase 3-anti-neutrophil cytoplasmic antibody (PR3-ANCA) positivity (odds ratio 3.19, 95% confidence interval 1.18-8.60) was an independent risk factor for ocular involvement, while sinonasal involvement (21.94, 2.54-189.69) and brain involvement (5.38, 1.50-19.31) were independent risk factors for ocular adnexal involvement. Antinuclear antibody (ANA) positivity was associated with optic nerve involvement (12.8, 1.80-90.5). Visual improvement occurred in 5 of 14 patients with optic nerve involvement, all of whom received intravenous (IV) immunosuppressive treatments beyond oral steroids within 2 months of visual impairment.

CONCLUSIONS

Ophthalmic involvement is common in Korean GPA patients and should be considered in the presence of PR3-ANCA, sinonasal or brain involvement. Patients with positive ANA have an increased risk of optic nerve involvement, and early IV immunosuppressive treatments beyond oral steroids are necessary to improve the visual outcome.

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.

Type of ANCA May Be Indispensable in Distinguishing Subphenotypes of Different Clinical Entities in ANCA-Associated Vasculitis

The traditional nomenclature system for classifying antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) based on clinical phenotype describes granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis (EGPA) and microscopic polyangiitis (MPA) as distinct clinical entities. This classification has proved its expedience in clinical trials and everyday clinical practice; yet, a substantial overlap in clinical presentation still exists and often causes difficulties in prompt definition and clinical distinction. Additionally, new insights into the AAV pathogenesis point out that PR3 and MPO-AAV may not represent expressions of the same disease spectrum but rather two distinct disorders, as they display significant differences. Thus, it is supported that a classification based on ANCA serotype (PR3-ANCA, MPO-ANCA or ANCA-negative) could be more accurate and also closer to the nature of the disease compared to the phenotype-based one. This review aims to elucidate the major differences between PR3 and MPO-AAV in terms of epidemiology, pathogenesis, histological and clinical manifestations and response to therapeutic approaches.

Time-dependent risk of mortality and end-stage kidney disease among patients with granulomatosis with polyangiitis

Objective

To describe the time-dependent impact of granulomatosis with polyangiitis (GPA) on the risk of mortality and end-stage kidney disease (ESKD). The results would provide valuable insight regarding the most vulnerable period for patients with GPA.

Methods

We conducted a retrospective cohort study using a nationally representative database in Taiwan. Patients with incident GPA without prior ESKD were identified, and non-GPA control cohorts were selected and matched to GPA cohorts based on sex, age, entry time and comorbidities in a 1:4 ratio. Cox regression model was used to estimate hazard ratios (HR) for mortality and ESKD stratified by the follow-up period.

Results

We identified a total of 142 GPA patients and 568 matched controls. Of those, 52 GPA patients died during follow-up, 48.1% of whom did so within the first 6 months after diagnosis. The 1-, 3-, 5-, and 10-year survival rates of GPA were 78.2, 71.2, 62.6, and 54.7%, respectively. Patients with GPA exhibited the greatest risk of mortality within the first 6 months after follow-up compared with non-GPA cohorts (HR: 21.9, 95% CI: 8.41–57.5). The mortality risk diminished after 1 year and to a marginally significant level during the follow-up period of 5–10 years (HR: 2.71, 95% CI: 0.97–7.62). Ten (7.1%) of the GPA patients experienced ESKD, and these cases occurred exclusively in the first 3 years following diagnosis.

Conclusion

Our findings suggest that physicians should closely monitor the treatment response and complications of patients with GPA in the first critical 6-month period after diagnosis to improve long-term survival outcome.

Relationship Between Gender and 1-Year Mortality in ANCA-Associated Vasculitis Patients: A Single-Center Retrospective Analysis and Meta-Analysis

Objective

The relationship between gender and short-term prognosis of patients with anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) is unclear, hence single-center retrospective analysis and meta-analysis were conducted to determine the relationship.

Methods

Initially treated patients with AAV were retrospectively enrolled. Data of clinical manifestation, laboratory indicators, Birmingham vasculitis activity score (BVAS), therapeutic treatments, and the patients' situations within 1 year were recorded. First, we compared the basic characteristics between male and female patients. Second, the risk factors associated with a 1-year mortality rate of patients with AAV were evaluated. Finally, a meta-analysis was performed to explore the effect of gender on 1-year mortality in patients with AAV.

Results

The study involved 84 patients with AAV, including 33 female and 51 male participants. In total, 14 people died (12 males and 2 females) and 70 survived in the 1st year. Statistical differences were noted in the age of onset, the course of the disease, WBC, HB, N, ESR, CRP, BUN, ALT and ALB, BVAS, and 1-year mortality rate between male and female participants. In male patients, elevated Scr, NLR, PLT, and RDW-CV were associated with poor AAV (P < 0.05) prognosis. The meta-analysis verified that male gender was an independent risk factor for the 1-year mortality of patients with AAV(OR = 1.54).

Conclusion

Significant sex-specific differences were found in patients with AAV. Male patients contributed to 1.54-fold of 1-year mortality risk in patients with AAV by meta-analysis. More attention should be paid to the mortality risk of male patients with AAV in the early stage.

Comparative study of granulomatosis with polyangiitis subsets according to ANCA status: data from the French Vasculitis Study Group Registry

Objective

To investigate whether antineutrophil cytoplasm antibody (ANCA)-negative and myeloperoxidase (MPO)-ANCA–positive granulomatosis with polyangiitis (GPA) differ from proteinase-3 (PR3)-ANCA–positive GPA.

Methods

Diagnostic characteristics and outcomes of newly diagnosed French Vasculitis Study Group Registry patients with ANCA-negative, MPO-ANCA–positive or PR3-ANCA–positive GPA satisfying American College of Rheumatology criteria and/or Chapel Hill Conference Consensus Nomenclature were compared.

Results

Among 727 GPA, 62 (8.5%) were ANCA-negative, 119 (16.4%) MPO-ANCA–positive and 546 (75.1%) PR3-ANCA–positive. ANCA-negative patients had significantly (p<0.05) more limited disease (17.7% vs 5.8%) and less kidney involvement (35.5% vs 58.9%) than those PR3-ANCA–positive or MPO-ANCA–positive, with comparable relapse-free (RFS) and overall survival (OS). MPO-ANCA–positive versus PR3-ANCA–positive and ANCA-negative patients were significantly more often female (52.9% vs 42.1%), older (59.8 vs 51.9 years), with more frequent kidney involvement (65.5% vs 55.2%) and less arthralgias (34.5% vs 55.1%), purpura (8.4% vs 17.1%) or eye involvement (18.5% vs 28.4%); RFS was similar but OS was lower before age adjustment. PR3-positive patients’ RFS was significantly lower than for ANCA-negative and MPO-positive groups combined, with OS higher before age adjustment. PR3-ANCA–positivity independently predicted relapse for all GPA forms combined but not when comparing only PR3-ANCA–positive versus MPO-ANCA–positive patients.

Conclusions

Based on this large cohort, ANCA-negative versus ANCA-positive patients more frequently had limited disease but similar RFS and OS. MPO-ANCA–positive patients had similar RFS but lower OS due to their older age. PR3-ANCA–positive GPA patients’ RFS was lower than those of the two other subsets combined but that difference did not persist when comparing only PR3 versus MPO-ANCA–positive patients.

Sex and Gender in Glomerular Disease

There is increasing understanding that a multifaceted interplay of sex-dependent genetic and immune dysregulation underpins the development of glomerular disorders. Regional and ethnic variations in glomerular disease incidence make delineating the effects of sex and gender on disease pathophysiology more complex, but there is a marked paucity of research in this area. This review article presents a summary of the current understanding of sex and gender in glomerular disease, highlighting the broader effects of sex and gender on autoimmunity, clinical presentations, and pathophysiology of individual glomerular diseases, as well as exploring sex, gender, and glomerular disease within a wider socioenvironmental context. It is important to specifically consider the effects of sex and gender when presenting and analyzing clinical and scientific studies on glomerular disease. Failure to do so risks promoting disparities within health care provision, neglecting opportunities to identify sex-specific biomarkers, and potentially hindering the development of sex-specific therapies.

Antineutrophil cytoplasmic antibody-associated interstitial lung disease: a review

Over the past three decades, an increasing number of publications have reported the association between interstitial lung disease (ILD) and anti-neutrophil cytoplasmic antibody (ANCA) or ANCA-associated vasculitis (AAV). With this increased awareness, we have reviewed the literature to date and provide an update in this narrative review. The vast majority of cases of ILD have been shown to be in the setting of positive anti-myeloperoxidase antibody and can be present in up to 45% of patients of microscopic polyangiitis, though cases of ILD associated with proteinase 3 ANCA have rarely been reported. Pulmonary fibrosis and ANCA positivity can occur with or without systemic involvement. The pathogenetic mechanisms establishing the relationship between ANCA and the development of pulmonary fibrosis remain unclear. Histologic and radiographic features of ANCA-ILD most commonly reveal usual interstitial pneumonia or non-specific interstitial pneumonia patterns, though other atypical features such as bronchiolitis have been described. ILD in the setting of AAV has been associated with worse outcomes, and thus early identification and treatment in these patients is appropriate. We advocate that ANCA antibody testing be performed as a baseline evaluation in patients presenting with idiopathic interstitial pneumonia. Suggested treatment of ANCA-ILD includes immunosuppression and/or antifibrotic agents, though supporting data and clinical trials to substantiate use of these therapies are needed.

Patterns of lung diseases predict survival in patients with MPO-ANCA-associated vasculitis: a single-center retrospective study

OBJECTIVES

This study aimed to explore differences in clinical features and prognosis among patients with varied myeloperoxidase (MPO) antineutrophil cytoplasmic antibody-associated vasculitis (MPO-AAV) associated lung diseases.

METHODS

Patients with MPO-AAV-associated lung diseases were enrolled in this retrospective cohort study at a single center. Clinical features and laboratory data at the time of diagnosis were compared among patients with various lung disease patterns. Kaplan-Meier and Cox regression analyses were performed to analyze overall survival.

RESULTS

A total of 155 patients were finally included and categorized into five groups, as follows: 72 had a usual interstitial pneumonia (UIP) pattern, 40 had non-UIP interstitial pneumonia, 18 had bronchiectasis (BR), 13 had necrotizing granuloma (NG), and 12 had diffuse alveolar hemorrhage (DAH). Among the five groups, patients with DAH had higher dyspnea and hemoptysis frequencies, lower PaO₂/FiO₂ levels, elevated C-reactive protein levels, and the poorest prognosis. The overall survival (OS) in the DAH group (median OS: 3.2 months) was significantly poorer than that in the NG group (median OS: not reached, log rank P < 0.001), the BR group (median OS: not reached, log rank P < 0.001), and the non-UIP IP group (median OS: 61.1 months, log rank P = 0.001). The UIP group had significantly more ex-smokers than the other groups (P < 0.001) and the second poorest survival (median OS: 39.1 months). The NG group tended to have female predominance, a higher incidence of ENT involvement, less severe renal involvement, and the best survival. After adjusting for multi-model Cox regression analysis, DAH and UIP (hazard ratio: 19.301 and 9.940, respectively, compared with NG) were independent predictors of all-cause mortality.

CONCLUSIONS

Various patterns of lung disease-associated MPO-AAV may potentially predict patient survival. Key Point • The present study described the clinical and prognostic features of various lung diseases-associated MPO-AAV, indicating the potential prediction for the survival of MPO-AAV patients.

Epidemiology and genetics of granulomatosis with polyangiitis

Granulomatosis with polyangiitis (GPA) previously known as Wegener's granulomatosis (WG) is a rare rheumatic disease affecting subjects of all ages. Prevalence and incidence of this systemic disease greatly varies across different ethnic groups. GPA is the commonest form of ANCA-associated vasculitis (AAV) with PR3 positivity among 85-95% of the cases. Scientific investigations of GPA is warranted because its severity, clinical heterogeneity, fast disease manifestation and end-organ damage. The etiology of GPA is still unknown. Major role of HLA and non-HLA genes with immune functions were identified, however, very limited replication was observed in different ethnic populations. In the present review, we have discussed the updates on the global epidemiology and contribution of HLA and major non-HLA genes/loci in GPA. We have also highlighted the cross disease association of GPA associated genes that may help in better disease management and predictive medicine. We proposed that high-resolution HLA typing and development of genetic risk model would help in early disease diagnosis and understanding the prognosis.

Exploratory classification of clinical phenotypes in Japanese patients with antineutrophil cytoplasmic antibody-associated vasculitis using cluster analysis

A novel patient cluster in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) may be identified in Japan. We performed multiple correspondence and cluster analysis regarding 427 clinically diagnosed AAV patients excluding eosinophilic granulomatosis with polyangiitis. Model 1 included the ANCA phenotype, items of the Birmingham Vasculitis Activity Score, and interstitial lung disease; model 2 included serum creatinine (s-Cr) and C-reactive protein (CRP) levels with model 1 components. In seven clusters determined in model 1, the ANCA-negative (n = 8) and proteinase 3-ANCA-positive (n = 41) groups emerged as two distinct clusters. The other five myeloperoxidase-ANCA-positive clusters were characterized by ear, nose, and throat (ENT) (n = 47); cutaneous (n = 36); renal (n = 256), non-renal (n = 33); and both ENT and cutaneous symptoms (n = 6). Four clusters in model 2 were characterized by myeloperoxidase-ANCA negativity (n = 42), without s-Cr elevation (< 1.3 mg/dL) (n = 157), s-Cr elevation (≥ 1.3 mg/dL) with high CRP (> 10 mg/dL) (n = 71), or s-Cr elevation (≥ 1.3 mg/dL) without high CRP (≤ 10 mg/dL) (n = 157). Overall, renal, and relapse-free survival rates were significantly different across the four clusters in model 2. ENT, cutaneous, and renal symptoms may be useful in characterization of Japanese AAV patients with myeloperoxidase-ANCA. The combination of s-Cr and CRP levels may be predictive of prognosis.

Impact of interstitial lung disease on mortality in ANCA-associated vasculitis: A systematic literature review and meta-analysis

Several retrospectivee described the association of interstitial lung disease (ILD) and ANCA-associated vasculitis (AAV). However, the relationship between the ILD and mortality in AAV patients have not been established so far. This study aims to estimate the relevance of AAV-associated-ILD (AAV-ILD) and mortality risk by conducting a systematic review and meta-analysis.A comprehensive systematic review was conducted in accordance with the guidelines of PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses). PubMed, Embase.com and the Cochrane Library (Wiley) were searched for original observational studies. Summary estimates were derived with a random-effects model and reported as risk ratio (RR), tested for publication bias and heterogeneity. Ten retrospective cohort studies were included, comprising 526 AAV-ILD patients enrolled from 1974 to 2018. Meta-analysis yielded a pooled RR of 2.90 (95% confidence interval 1.77–4.74) for death among those with AAV-ILD compared to control group. UIP pattern was associated with an even poorer prognosis in comparison to non-UIP pattern (RR 4.36, 95% confidence interval 1.14–16.78). Sensitivity analysis suggested that the meta-RR result was not skewed by a single dominant study. ILD might be associated with a higher mortality risk in AAV patients.

The association between ear involvement and clinical features and prognosis in ANCA-associated vasculitis

OBJECTIVE

The concept of otitis media with ANCA-associated vasculitis (OMAAV) was recently proposed by the study group of the Japan Otological Society. However, little is known about the effect of ear involvement on the clinical features and prognosis of AAV. We investigate this issue in this study.

METHODS

We retrospectively examined 36 patients diagnosed with OMAAV and 44 patients diagnosed with AAV without ear involvement (non-OMAAV) at Ehime University Hospital from 2013 to 2018. We collected serological findings including ANCA type and titer, C-reactive protein (CRP), serum creatinine level, organ involved at initial diagnosis, treatment, remission, disease relapse, and mortality from medical records. We investigated whether clinical features and outcomes differed between the OMAAV and non-OMAAV groups.

RESULTS

Age, ANCA titer, and CRP at initial diagnosis were not significantly different between the two groups, and the rate of intravenous cyclophosphamide (IVCY) use also did not differ. The proportions of patients with concurrent eye involvement, facial palsy (FP), and hypertrophic pachymeningitis (HCP) were significantly higher in the OMAAV than in the non-OMAAV group (p = 0.005, 0.005 and 0.049, respectively), while both renal and peripheral nerve involvement were significantly less common in OMAAV patients (p = 0.04). Among the 30 patients with renal involvement, serum creatinine level at diagnosis was significantly lower in the OMAAV group (p = 0.04). The mortality rate was 8.3% in OMAAV and 6.8% in non-OMAAV cases, but this difference was not significant. The rate of relapse was 33.3% in OMAAV and 13.6% in non-OMAAV cases; this difference was significant (p = 0.04).

CONCLUSIONS

Serological measurements of disease activity did not differ between the groups. Eye involvement, FP, and HCP, however, were significantly more common in AAV with ear involvement. In addition, renal involvement was less common and renal impairment was milder in AAV with ear involvement. These findings can be considered clinical features. The relapse rate was significantly higher in AAV with ear involvement.

Rituximab maintenance therapy for patients with antineutrophil cytoplasmic antibody-associated vasculitis in Japan

OBJECTIVES

We examined the efficacy and safety of rituximab (RTX) maintenance therapy for patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in Japan.

METHODS

We conducted a retrospective study using a multi-center cohort database of vasculitis patients. All maintenance treatment courses were divided into three groups: a RTX group, a group treated with other immunosuppressant drugs (IS) and a group receiving glucocorticoid monotherapy (GC). The primary endpoint was the comparison of relapse-free survival after 1 year. We also analyzed the occurrence of severe adverse events (SAEs) to assess safety.

RESULTS

We included 123 courses of 107 patients (RTX n = 14, IS n = 64, GC n = 45). Twelve of 14 in the RTX group patients were diagnosed with granulomatosis with polyangiitis (GPA). The relapse-free survival of RTX maintenance therapy was comparable to that in the other groups (p = .122). After 1 year of treatment, the RTX group was administered lower steroid doses and one-third of them could withdraw corticosteroid. The overall incidence of SAE was 0.54/patient-year in the RTX group, 0.39/patient-year in the IS group and 0.34/patient-year in the GC group.

CONCLUSION

RTX maintenance therapy could be effective and safe in Japanese GPA patients.

Clinical impact of subgrouping ANCA-associated vasculitis according to antibody specificity beyond the clinicopathological classification

OBJECTIVES

In ANCA-associated vasculitis (AAV), classifications have emerged to individualize homogeneous clinical and outcomes patterns, including the recently defined anti-MPO granulomatosis with polyangiitis (GPA) subgroup. This study aimed to retrospectively evaluate the impacts of re-classification based on clinicopathological criteria and/or ANCA specificity.

METHODS

A retrospective monocentric study conducted at Caen University Hospital led to the identification of PR3 or MPO-ANCA AAV patients from January 2000 or September 2011, respectively, to June 2016. Eosinophilic GPA patients were excluded. AAVs were thereby also classified either as GPA or microscopic polyangiitis (MPA) according to the European Medicines Agency vasculitis algorithm.

RESULTS

A total of 150 AAV patients were included (94 GPA, 56 MPA; 87 anti-PR3 and 63 anti-MPO patients). GPA patients exhibited a worse relapse-free survival but a better renal survival (P < 0.001 and P = 0.021, respectively) than MPA patients. Overall, relapse-free and renal survival rates were similar between anti-PR3 and anti-MPO patients (P = 0.35, 0.17 and 0.15, respectively). Similarly, the prognosis was identical between anti-MPO MPA patients and anti-PR3 MPA patients (P = 0.33, 0.19 and 0.65, respectively), and between anti-MPO GPA patients and anti-PR3 GPA patients (P = 0.06, 0.99 and 0.64, respectively). Moreover, anti-PR3 GPA and anti-MPO GPA patients exhibited no differences in clinical manifestations or BVAS score.

CONCLUSION

Clinicopathological classification appeared to be the strongest criterion for distinguishing among homogeneous prognoses of AAV. Individualizing the anti-MPO GPA subgroup does not appear to bring additional value to clinical practice, but multicentre studies are required to confirm this trend.

Clinical characteristics of patients with vasculitis positive for anti-neutrophil cytoplasmic antibody targeting both proteinase 3 and myeloperoxidase: a retrospective study

Anti-neutrophil cytoplasmic antibody (ANCA) may target proteinase 3 (PR3) or myeloperoxidase (MPO). Although a few patients with vasculitis have both MPO- and PR3-ANCA, the details of their clinical characteristics are not known. The objective of this study was to analyze the characteristics of patients with dual MPO- and PR3-ANCA-positive vasculitis. The medical records of patients with ANCA and vasculitis confirmed by biopsy were reviewed. The age at diagnosis, sex, and data on organ involvement of the kidney, lung, upper airways, skin, nervous system, and gastrointestinal tract were collected. Clinical variables were analyzed according to ANCA specificity. Of 85 patients with ANCA and vasculitis included in this study, 67 (78.8%) had MPO-ANCA, 10 (11.8%) had PR3-ANCA, and 8 (9.4%) had both MPO- and PR3-ANCA. Patients with MPO- PR3 + ANCA-associated vasculitis (AAV) were younger at diagnosis (median, 54.4 years; p < 0.05) than patients with MPO + PR3- AAV (67.0 years) or dual-ANCA AAV (MPO + PR3 + , 68.5 years). The initial glomerular filtration rate in patients with MPO + PR3- AAV (22.0 ml/min) was significantly lower than that in patients with MPO- PR3 + AAV (108.6 ml/min, p < 0.05), but was not different from that in dual-ANCA AAV patients (16.5 ml/min). Upper airway involvement also differed with ANCA type (MPO+ PR3- , 35.8% vs. MPO- PR3 + , 70.0% vs. MPO + PR3+ , 75.0%, p < 0.05). The involvement of other organs did not differ according to ANCA type. Age at diagnosis, kidney involvement, and upper airway involvement were associated with ANCA type. Patients with dual-ANCA-positive vasculitis had considerably more kidney dysfunction than patients with MPO- PR3+ AAV. They also had more upper airway involvement than patients with MPO+ PR3- AAV.

The Association of Airway Comorbidities With the Clinical Phenotypes and Outcomes of Patients With Antineutrophil Cytoplasmic Autoantibody-associated Vasculitis

OBJECTIVE

We investigated the association of airway comorbidities with the clinical phenotypes and outcomes of myeloperoxidase (MPO)-antineutrophil cytoplasmic antibodies (ANCA)-positive ANCA-associated vasculitis (AAV).

METHODS

An AAV patient multicenter cohort trial was established in 13 hospitals in western Japan between 2012 and 2018. We examined 143 of the new-onset MPO-ANCA-positive AAV patients. Their clinical characteristics and comorbidities at disease onset were compared based on clinical phenotypes. Multivariate analysis was performed to identify factors predictive of remission and death.

RESULTS

Twenty-seven cases with granulomatosis with polyangiitis (GPA), 10 with eosinophilic GPA (EGPA), 81 with microscopic polyangiitis (MPA), and 25 with unclassified AAV were identified. The average age of MPO-ANCA-positive patients was 71.4 years. Comorbidity (87.4%) and airway comorbidity (70.6%) were frequently observed in these patients. Examination of the clinical phenotypes revealed that the cases of GPA were frequently accompanied by infectious airway comorbidity (upper airway disease, bronchiectasis, pulmonary infections), and most of the cases of MPA and unclassified AAV were accompanied by fibrotic interstitial lung disease (fILD) or emphysema. Among MPO-ANCA-positive patients, infectious airway comorbidity was predictive of both remission (HR 1.58, P = 0.03) and mortality (HR 2.64, P = 0.04), and fILD was predictive of mortality (HR 7.55, P = 0.008). The combination of infectious airway comorbidities and fILD caused the worst survival outcomes in patients.

CONCLUSION

MPO-ANCA-positive AAV was frequently accompanied by airway comorbidities. In addition to fILD, infectious airway comorbidities were closely associated with those clinical phenotypes and outcomes.

Unusual manifestations of giant cell arteritis and granulomatosis with polyangiitis

Giant cell arteritis (GCA) is a type of large vessel vasculitis, and it involves the aorta, large vessels and terminal branches of the external carotid artery, especially the temporal artery. Temporal artery biopsy is a simple tool for the diagnosis of vasculitis, however, the histopathological findings do not always differentiate between the small-vessel vasculitis and GCA. We report the case of 72-year-old male who initially had a clinical diagnosis of GCA, then in the course of treatment, diagnostic histopathological approach revealed the necrotizing vasculitis with bronchocentric granulomatosis in the inflammatory nodule of the lung. The manifestations of patients with systemic vasculitis represent the disorders of multiple organ systems thus are diverse and may vary through the course of the disease. Presentation of unexpected features such as insufficient response to antibiotics, sinusitis, runny nose, discomfort of frontal region or pachymeningitis which anticipates re-evaluation of systemic vasculitis that may lead us to an appropriate diagnosis and the treatment.

Clinical characteristics of patients with granulomatosis with polyangiitis and microscopic polyangiitis in ENT practice: a comparative analysis

ENT manifestations are commonly observed in patients with small vessel vasculitis (SVV). The main aim of this study was to analyse and present the clinicopathological characteristics of individuals with SVV emphasising otorhinolaryngological symptoms. This study evaluated 64 patients, 41 with granulomatosis with polyangiitis (GPA) and 23 with microscopic polyangiitis (MPA). Herein, we compare the clinicopathologic features of GPA and MPA. The average age at diagnosis was 50.2 and 56.2 years, for GPA and MPA, respectively. 57 patients (89%) were antineutrophil cytoplasmic antibody (ANCA) positive, 34 (59.6%) for anti-proteinase 3 (PR3)-ANCA and 21 (36.8%) for myeloperoxidase (MPO)-ANCA. 7 patients (10.9%) were ANCA negative. The most commonly affected organs were lungs (76.56%), ear, nose, throat (ENT) (75%) and kidneys (73.44%). ENT disorders mainly appeared as chronic rhinosinusitis and epistaxis and preceded SVV diagnosis by an average 14.4 months. In the majority of patients, ENT disorders were the first symptoms of SVV and preceded its systemic transformation. Pulmonary, ENT and nervous manifestations were more common in GPA, whereas the prevalence of renal, gastrointestinal, cutaneous, cardiovascular and ocular disorders was higher in MPA. The results of our study emphasise the high prevalence of ENT symptoms in patients with SVV, especially in those with GPA. We highlight the significant role of the otorhinolaryngologist in early SVV diagnosis and management. Any patient with persistent ENT symptoms or ENT dysfunctions not responding to standard otorhinolaryngological treatment should be precisely and rapidly evaluated for the presence of systemic dysfunctions (especially renal and pulmonary). Realising the differences and similarities between GPA and MPA is crucial in undelayed SVV diagnosis and proper treatment.

Prostate involvement in granulomatosis with polyangiitis

To present a case of prostate involvement (PI) in granulomatosis polyangiitis (GPA) and analyse related published reports. We employed the following keywords for retrieving reports indexed by MEDLINE/PubMed and/or Scopus: "granulomatosis with polyangiitis", "Wegener granulomatosis" and "prostate involvement". Additional searches were performed through Google Scholar and HINARI. All cases that fulfilled the American College of Rheumatology criteria for GPA, standards of Chapel Hill Consensus Conference, and did not match with exclusion criteria were analysed and summarised. A 35-year-old man presented with complaints of stuffy nose, difficulty breathing through the nose, swelling and pain in the left half of the nose, low-grade fever, and discomfort. The nasal mucosal biopsy did not reveal any specific changes. During the inpatient treatment, he developed eye redness, tearing, dysuria, and decreased urinary stream. Prostate-specific antigen (PSA) was elevated (2.81 μg/L; normal values ≤ 1.4 μg/L for males below 40 years). Prostate biopsy findings were consistent with diagnosis of GPA, which was confirmed by detecting elevated anti-PR3 antibodies (4.1 IU; normal values < 1.0 IU). We analysed our case in view of the clinical course of 45 published cases of PI in GPA. PI in GPA is a rare clinical manifestation of the vasculitis. Patients with atypical clinical symptoms of GPA are at risk of delayed diagnosis. The awareness of variable clinical presentations of GPA, particularly specific affection of the prostate gland, is crucial for timely diagnosis.

Distinction between MPO-ANCA and PR3-ANCA-associated glomerulonephritis in Chinese patients: a retrospective single-center study

OBJECTIVES

To retrospectively investigate the clinical and histological features and outcomes of ANCA-associated glomerulonephritis (AAGN) with different ANCA serotypes.

METHOD

A total of 467 AAGN patients were divided into MPO-AAGN (MPO) and PR3-AAGN (PR3) groups according to ANCA serotype. Clinical and histological features and renal outcomes were compared.

RESULTS

In this study, 429 (91.9%) patients tested positive for MPO-ANCA, and 38 (8.1%) for PR3-ANCA. The median age at diagnosis (P = 0.017) and proportion of females (P = 0.003) were higher in the MPO group. Joint (P < 0.001), ENT (P = 0.000), skin (P = 0.007), and eye (P = 0.014) involvements were more common in the PR3 group. Compared with that in the PR3-group, a higher proportion of patients in the MPO group had microscopic polyangiitis (P = 0.000), and a lower proportion of exhibited granulomatosis with polyangiitis (P = 0.000). Patients in the MPO group also exhibited lower BVAS scores (P = 0.003) and higher serum albumin levels (P = 0.009). Histologically, a lower proportion of MPO patients had crescentic glomerulonephritis (P = 0.028) and acute tubule-interstitial lesion scores (P = 0.007), but a higher proportion of these patients exhibited mixed class glomerulonephritis (P = 0.032) than in the PR3 group. The relapse rate was lower (P = 0.020), and the 5-year relapse-free survival rate (P = 0.003) was higher in the MPO group than in the PR3 group. However, the 5-year renal survival rates (P = 0.106) were not significantly different.

CONCLUSIONS

MPO-ANCA was predominant in Chinese patients with ANCA-associated vasculitis and renal disease. The epidemiological characteristics, extra-renal involvement, and histopathological classes and outcomes were different between MPO-positive and PR3-positive patients, implying that they might be two different disease entities.

Is granulomatosis with polyangiitis in Asia different from the West?

The incidence and clinical features of antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV) have been shown to vary according to geographical areas, with granulomatosis with polyangiitis (GPA) being more common in northern Europe and microscopic polyangiitis (MPA) being more common in Asian countries. The annual incidence of GPA among Asians varies between 0.37/million to 2.1/million population. The prevalence of GPA has been estimated to be 1.94/100 000 in a Chinese population. Polymorphisms in class II major histocompatibility genes and ETS1 proto-oncogene has been shown in Asian patients with GPA. There is a difference in mean age at onset and proteinase 3 (PR3) or myeloperoxidase (MPO) positivity in GPA patients from different Asian countries. Those from India had mean age of 40 years and those from Japan had mean age of 65 years. Sixty percent of GPA patients from China and Japan were MPO ANCA positive while the majority of patients from India and Korea were PR3 positive. Geographical variation with lower frequency of renal involvement in Indian studies and higher frequency in Chinese patients has also been noted. Treatment outcomes have been similar to those reported from other parts of the world. Remission was achieved in about two-thirds of patients while relapses were noted in one-third to half of the patients. Apart from minor differences in the organ systems involved, MPO-ANCA GPA and PR3-ANCA GPA had similar rates of remission and relapses.

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.

Clinical Predictors of Outcome in Patients with Anti-neutrophil Cytoplasmic Autoantibody-related Renal Vasculitis: Experiences from a Single-center

Background:

Primary anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a chronic autoimmune disease associated with multisystem dysfunction. Renal involvement is common and closely associated with outcome. The purpose of this study was to investigate the clinical determinants of mortality of patients with AAV-related renal injury in the first 2 years after diagnosis in a single West Chinese center.

Methods:

Demographic and laboratory parameters of 123 consecutive patients with AAV-related renal injury diagnosed in Renal Division and Institute of Nephrology, Sichuan Provincial People's Hospital between 2004 and 2012 were collected retrospectively. All patients were followed up for 2 years after diagnosis. Survivors were compared with nonsurvivors to identify the clinical baseline variables associated with mortality. Multivariate Cox regression model was used to determine the independent predictors of mortality.

Results:

Of the 123 patients, 46 (37.4%) died by the end of 2 years after diagnosis, with 41 (33.3%) patients dying within the first 12 months. In comparison with the survivors, Birmingham Vasculitis Activity Score (BVAS), the incidence of pulmonary hemorrhage and digestive system (DS) involvement, serum creatinine, and erythrocyte sedimentation rate were significantly higher in nonsurvivors, whereas lymphocyte counts, hemoglobin, and complement 3 (C3) were significantly lower. Renal replacement therapy was more common in nonsurvivors. High BVAS (hazard ratio [HR] = 1.058, 95% confidence interval [CI]: 1.002–1.117; P = 0.042), pulmonary hemorrhage (HR = 1.970, 95% CI: 1.033–3.757; P = 0.04), DS involvement (HR = 2.911, 95% CI: 1.212–6.911; P = 0.017), and serum creatinine >400 μmol/L (HR = 2.910, 95% CI: 1.271–6.664; P = 0.012) were independent predictors of death in patients with AAV-related renal injury.

Conclusions:

Patients with AAV-related renal injury have high early mortality. Those with high BVAS (particularly with pulmonary or DS involvement) and serious renal dysfunction should receive aggressive therapy and careful monitoring to reduce the occurrence of adverse events and improve prognosis.

Myeloperoxidase-Antineutrophil Cytoplasmic Antibody (ANCA)-Positive and ANCA-Negative Patients With Granulomatosis With Polyangiitis (Wegener's): Distinct Patient Subsets

OBJECTIVE

To examine the relationship of antineutrophil cytoplasmic antibody (ANCA) type and ANCA-associated vasculitis (AAV) diagnosis with demographic features, disease manifestations, and clinical outcomes. We focused on patients who account for the differences between ANCA type and disease type classifications: anti-myeloperoxidase (MPO)-ANCA-positive and ANCA-negative patients with granulomatosis with polyangiitis (Wegener's) (GPA).

METHODS

We performed a pooled analysis of the Wegener's Granulomatosis Etanercept Trial and the Rituximab in ANCA-Associated Vasculitis trial comparing patients with MPO-ANCA-positive GPA and patients with ANCA-negative GPA to patients with proteinase 3 (PR3)-ANCA-positive GPA and patients with MPO-ANCA-positive microscopic polyangiitis (MPA).

RESULTS

Of the 365 patients analyzed, 273 (75%) had PR3-ANCA-positive GPA, 33 (9%) had MPO-ANCA-positive GPA, 15 (4%) had ANCA-negative GPA, and 44 (12%) had MPO-ANCA-positive MPA. MPO-ANCA-positive GPA patients were younger at diagnosis compared to MPO-ANCA-positive MPA patients (53 versus 61 years; P = 0.02). Their disease manifestations and rates of relapse were similar to those of PR3-ANCA-positive GPA patients. Relapse was more frequent in MPO-ANCA-positive GPA patients than in patients with MPO-ANCA-positive MPA at trial entry as well as at 12 and 18 months. ANCA-negative patients with GPA had lower Birmingham Vasculitis Activity Score for Wegener's Granulomatosis scores at trial entry than PR3-ANCA-positive patients with GPA (4.5 versus 7.7; P < 0.01), primarily because of a lower prevalence of renal involvement.

CONCLUSION

We were unable to demonstrate important clinical differences between MPO-ANCA-positive and PR3-ANCA-positive patients with GPA. The risk of relapse was associated more closely with disease type than with ANCA type in this patient cohort. These findings deserve consideration in the assessment of relapse risk in patients with AAV.

Thoracic intradural extramedullary lesions causing progressive myelopathy as an initial manifestation of granulomatosis with polyangiitis: a case report and review of literature

CONTEXT

To our knowledge, only a few reports regarding the spinal involvement of granulomatosis with polyangiitis (GPA)-also termed as Wegener's granulomatosis-have been published. However, all these cases reportedly exhibited epidural tumor-like lesions or dural thickening.

FINDINGS

We report the case of a 57-year-old woman with progressive myelopathy caused by multiple spinal lesions with GPA, which appeared to be protruding inwards, within the dura mater, on magnetic resonance imaging (MRI); these lesions were difficult to distinguish from intradural tumors. Moreover, these lesions exhibited low intensity on both T1- and T2-weighted MRI, and showed prominent enhancement on gadolinium-contrast imaging. Resection biopsy was effective for both diagnosis and the recovery of the neurological deficit.

CONCLUSION

Based on these findings, we suggest that GPA lesions can exhibit variable patterns in the spine. Nevertheless, clinicians should consider the possibility of GPA in such cases, particularly when multiple, inwardly protruding tumor-like lesions are detected within the dura mater on MRI.

Myeloperoxidase Anti-Neutrophil Cytoplasmic Antibody-Positive Interstitial Pneumonia Associated with Granulomatosis with Polyangiitis Diagnosed by Surgical Lung Biopsy

Granulomatosis with polyangiitis (GPA) is a rare systemic vasculitis that often involves the lung. However, interstitial pneumonia (IP) is rarely seen in GPA patients. We herein report 3 cases of IP associated with GPA diagnosed by surgical lung biopsy. High-resolution CT showed uniform subpleural reticular opacity with traction bronchiectasis. Biopsies from all 3 patients revealed neutrophilic capillaritis, microabscesses with giant cells, and coexisting histological findings of usual IP pattern or fibrosing nonspecific IP pattern. All 3 patients had elevated levels of serum myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA), but not proteinase 3-ANCA. We diagnosed GPA and treated with corticosteroid and cyclophosphamide. Follow-up CT showed improvement of the lesions in all patients. Surgical lung biopsy specimens which revealed GPA enabled us to conduct the most suitable therapy. This report indicates the importance of surgical lung biopsy for differentiating idiopathic IPs from GPA-associated IP and suggests a relationship between MPO-ANCA and IP in GPA.

Comparative investigation of respiratory tract involvement in granulomatosis with polyangiitis between PR3-ANCA positive and MPO-ANCA positive cases: a retrospective cohort study

Background

The clinical characteristics of myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) positive granulomatosis with polyangiitis (GPA) remain unclear, as does the difference between MPO-ANCA positive GPA and proteinase 3 (PR3)-ANCA positive GPA, especially with regard to the details of respiratory tract involvement. We investigated the differences in clinical, radiological, and histopathological features between PR3-ANCA positive GPA and MPO-ANCA positive GPA.

Methods

We retrospectively reviewed 16 patients who were newly diagnosed with GPA between December 2000 and July 2014. One patient, who was positive for both PR3-ANCA and MPO-ANCA, was excluded. Our review was based on the European Medicine Agency (EMA) algorithm.

Results

Fifty-six percent of GPA patients were positive for PR3-ANCA, 38 % for MPO-ANCA, and the remaining 6 % for both. The MPO-ANCA positive group included a greater number of females (67 %). There were no statistically significant differences in laboratory data, symptoms and signs, Birmingham Vasculitis Activity Score, or CT findings between the two groups. As for upper respiratory tract involvement, the most common manifestation was paranasal sinusitis, whereas lung nodules were most common as the lower respiratory tract involvement in both groups. Although the combination therapy with prednisone and cyclophosphamide was the most common initial treatment in both groups, the relapse rate in MPO-ANCA positive cases was lower than that of PR3-ANCA positive cases (17 % and 56 %, respectively).

Conclusion

A high prevalence of MPO-ANCA positive GPA was noted. No significant differences in clinico-radiological findings were observed except for the prevalence of relapse between the PR3-ANCA positive cases and MPO-ANCA positive cases, suggesting that the type of ANCA may be of little help in the diagnosis of GPA. Examination for granulomatous findings in the respiratory tract is important, even in MPO-ANCA positive cases. There is a need to accumulate more cases and conduct a further investigation in the future.