Hypotheses on the etiology of antineutrophil cytoplasmic autoantibody associated vasculitis: the cause is hidden, but the result is known

Malignancy is increased in patients with antineutrophil cytoplasmic antibody-associated vasculitis in China

OBJECTIVE

It has been reported that in western countries malignancy risk was higher in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) compared with that in the general population. In the current study, we investigated the incidence, spectrum and risk factors of malignancy in Chinese AAV patients.

METHODS

AAV patients diagnosed from 1995 to 2021 in Peking University First Hospital with a follow-up more than 12 months were recruited. Standardized incidence ratios (SIR) were calculated to describe the risk of malignancy, adjusted for sex, age and follow-up time.

RESULTS

A total of 552 AAV patients were recruited, among which 23 patients had malignancies either preceding or concurrent with AAV diagnosis, and 43 of the remaining 529 patients developed malignancies within 4.3 ± 4.2 years post AAV diagnosis (SIR: 2.24; 95% CI: 1.68-2.99; p < 0.001). Among these 66 patients, twenty different sites of malignancy were observed, lung cancer being most frequent. To get exactly expected malignancies for the calculation of SIR, 529 patients without preceding or concurrent malignancies were included in the following analysis. Lung cancer was still the leading malignancy diagnosis (SIR: 5.01; 95% CI: 3.29-7.62), followed by malignancies in the kidney, bladder, ureter and prostate. Male gender (HR:2.84; 95%CI:1.36-5.96; p = 0.006) and older age (per year, HR:1.04; 95%CI:1.00-1.07; p = 0.038) were significantly associated with increased risk of malignancy. For patients with malignancy developed beyond 5 years after the diagnosis of AAV, a significantly higher malignancy risk was observed in those with a cumulative cyclophosphamide dose over 20.0 g (SIR: 11.54; 95% CI: 4.77-27.93; p < 0.001). Within the first 2 years after the diagnosis of AAV, the risk of malignancy was still significantly higher than that in the general population, but the cumulative cyclophosphamide dose was not significantly associated with malignancy occurrence in this subgroup of patients.

CONCLUSIONS

Malignancy risk is higher in Chinese AAV patients than that in the general population, with a different malignancy spectrum from western countries. Both the use of cyclophosphamide and AAV per se might be associated with higher incidence of malignancy occurrence.

ANCA-Associated Vasculitis: Practical Issues in Management

ANCA associated vasculitides are multi-system autoimmune diseases which are increasing in prevalence. In this review we will discuss the clinical manifestations and review the management options. We highlight the various trials of induction and maintenance therapy and discuss the areas of unmet need. These include understanding which patients are at highest risk of relapse, clinical adaptation of improved biomarkers of disease activity and tools to discuss long term prognosis.

Unilateral Diffuse Alveolar Hemorrhage as an Initial Presentation of Microscopic Polyangiitis

Diffuse alveolar hemorrhage (DAH) is a life-threatening condition due to widespread damage to small pulmonary vessels commonly caused by systemic vasculitis. Alveolar involvement is typically multi-lobar and bilateral. It frequently presents as bilateral diffuse airspace opacities on chest imaging. Unilateral DAH is rare. Patients presenting with hemoptysis, anemia, hypoxemia, progressive dyspnea, and opacities on chest imaging should be evaluated for systemic vasculitis such as antineutrophilic cytoplasmic antibody (ANCA) vasculitis. We report the case of a 23-year-old female who presented with hemoptysis, severe dyspnea, hypoxemia, anemia, and oliguria. The laboratory exam results showed the patient to be p-ANCA positive, which suggests a diagnosis of microscopic polyangiitis. Chest X-ray showed unilateral airspace opacities, and DAH was confirmed by hemosiderin-laden macrophages on bronchoalveolar fluid histopathological examination. After treatment with plasmapheresis, intravenous methylprednisolone pulse, and cyclophosphamide, the patient's symptoms and radiographic findings improved.

T lymphocyte subsets and immunoglobulin and complement levels are associated with the infection status of patients with antineutrophil cytoplasmic antibody-associated vasculitis

BACKGROUND

Infection is the leading cause of death in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). The aim of this study was to characterize the immunological features of infectious events occurring in patients with newly diagnosed AAV and to identify possible risk factors associated with infection.

METHODS

The T lymphocyte subsets, immunoglobulin, and complement levels of the groups were compared between infected group and the noninfected group. Further, regression analysis was conducted to determine the association of each variable with the risk of infection.

RESULTS

280 patients with newly diagnosed AAV were enrolled. The average levels of CD3+ T cells (720.0 vs. 920.5, P < 0.001), CD3+CD4+ T cells (392.0 vs. 547.0, P < 0.001), and CD3+CD8+ T cells (248.0 vs. 335.0, P = 0.001), serum IgG (11.66 g/L vs. 13.59 g/L, P = 0.002), IgA (1.70 g/L vs. 2.44 g/L, P < 0.001), C3 (1.03 g/L vs. 1.09 g/L, P = 0.015), and C4 (0.24 g/L vs. 0.27 g/L, P < 0.001) were significantly lower in the infected group than in the noninfected group. The levels of CD3+CD4+ T cells (adjusted OR 0.997, P = 0.018), IgG (adjusted OR 0.804, P = 0.004), and C4 (adjusted OR 0.001, P = 0.013) were found independently associated with infection.

CONCLUSIONS

Patients of infected AAV and those without infection differ in T lymphocyte subsets and immunoglobulin and complement levels. Furthermore, CD3+CD4+ T cells counts and serum IgG and C4 levels were independent risk factors with infection in patients with newly diagnosed AAV.

Subsequent COVID-19 Prophylaxis in COVID-19 Associated Glomerulopathies

Successful vaccination has been the decisive factor in the overall decline of SARS-CoV2 infection related morbidity and mortality. However, global effects of the COVID-19 pandemic are ongoing, with reports of glomerular disease occurring in relation to both infection and vaccination. A particular rise in anti-GBM disease has been identified. Information is still emerging regarding the optimal management of such cases. We reviewed anti-GBM antibody detection rates at our test center over the past 5 years. We followed three patients with biopsy confirmed glomerular disease temporally related to COVID-19 vaccination. Each patient proceeded to receive subsequent COVID-19 vaccination as per immunologist recommendations. Further assessment included COVID-19 antibody testing in each case. A three-fold increase in significant anti-GBM antibody results noted at our center was associated with COVID infection in 10% of cases, and COVID vaccination in 25% of cases. We demonstrated that subsequent vaccination did not appear to lead to adverse effects including relapse in our three cases of COVID-19 vaccine-associated GN. We also identified positive COVID-19 antibody levels in two out of three cases, despite immunosuppression. We report a rise in anti-GBM antibody disease incidence. Our small study suggests that COVID-19 antibody testing can help determine COVID prophylaxis requirements, and subsequent vaccination with an alternative vaccine type appears safe.

Plasma exchange as an adjunctive therapy in anti-neutrophil cytoplasm antibody-associated vasculitis

INTRODUCTION

We summarize evidence for the role of therapeutic plasma exchange (TPE) in the treatment of anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV). TPE rapidly removes ANCA IgG, complement and coagulation factors important in the pathogenesis of AAV. TPE has been used in patients with rapidly deteriorating renal function to achieve early disease control, allowing time for immunosuppressive agents to prevent resynthesis of ANCA. The PEXIVAS trial challenged the utility of TPE in AAV, as it did not show benefit of adjunctive TPE on a combined end point of end stage kidney disease (ESKD) and death.

AREAS COVERED

We analyze data from PEXIVAS and other trials of TPE in AAV, an up-to-date meta-analysis, and recently published large cohort studies.

EXPERT OPINION

There remains a role for the use of TPE in AAV in certain groups of patients, in particular those with severe renal involvement (Cr >500 μmol/L or dialysis-dependent). It should be considered in patients with Cr >300 μmol/L and rapidly deteriorating function, or with life-threatening pulmonary hemorrhage. A separate indication is patients double positive for anti-GBM antibodies and ANCA. TPE may have the greatest benefit as part of steroid-sparing immunosuppressive treatment strategies.

Toll-like Receptor 9 Induced Dendritic Cell Activation Promotes Anti-Myeloperoxidase Autoimmunity and Glomerulonephritis

ANCA-associated vasculitis (AAV) is intricately linked with infections. Toll-like receptors (TLR) provide a potential link between infection and anti-myeloperoxidase (MPO) autoimmunity. TLR9 ligation has been shown to promote anti-MPO autoimmunity and glomerular vasculitis in murine MPO-AAV. This study investigates dendritic cell TLR9 ligation in murine experimental anti-MPO glomerulonephritis. We analyzed autoimmune responses to MPO following transfer of TLR9 stimulated, MPO pulsed dendritic cells and kidney injury following a sub-nephritogenic dose of sheep anti-mouse glomerular basement membrane globulin. TLR9 ligation enhanced dendritic cell activation upregulating CD40 and CD80 expression, promoting systemic anti-MPO autoimmunity and T cell recall responses and exacerbating kidney injury. CD40 upregulation by TLR9 was critical for the induction of nephritogenic autoimmunity. The presence of DEC205, which transports the TLR9 ligand to TLR9 located in the endosome, also promoted kidney injury. This confirms TLR9 mediated dendritic cell activation as a mechanism of anti-MPO autoimmunity in AAV and further defines the link between infection and the generation of MPO specific autoimmune inflammation.

De-Novo Antineutrophil Cytoplasmic Antibody-Associated Vasculitis Following the mRNA-1273 (Moderna) Vaccine for COVID-19

Antineutrophil cytoplasmic antibody (ANCA) is a systemic autoimmune disorder characterized by antibodies directed against small- and moderate-sized vessels. While there are few reported cases of autoimmune illnesses associated with influenza vaccination, two cases of de-novo anti-proteinase (PR3) ANCA-associated pauci immune glomerulonephritis are reported after the mRNA-1273 coronavirus disease 2019 (COVID-19) vaccine. Here, we report the third case of ANCA-associated glomerulonephritis after the mRNA-1273 COVID-19 vaccine. Our patient presented with acute kidney injury and sub-nephrotic proteinuria four days after receiving the second dose of the COVID vaccine. He was found to have elevated c-ANCA and anti-PR3 antibodies. Renal biopsy confirmed focal necrotizing and diffuse crescentic glomerulonephritis. He was diagnosed with pauci immune glomerulonephritis. The patient achieved remission 10 weeks after the diagnosis with successful treatment.

The neutrophil-to-lymphocyte ratio as a marker of vasculitis activity, severe infection and mortality in anca-associated vasculitis: A retrospective study

INTRODUCTION

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a multisystemic disease. Despite the improvement in mortality rate since the introduction of immunosuppression, long-term prognosis is still uncertain not only because of the disease activity but also due to treatment associated adverse effects. The neutrophil-to-lymphocyte ratio (NLR) has been demonstrated as an inflammatory marker in multiple settings. In this study, we aimed to investigate the prognostic ability of the NLR in AAV patients.

METHODS

We conducted a retrospective analysis of the clinical records of all adult patients with AVV admitted to the Nephrology and Renal Transplantation Department of Centro Hospitalar Universitário Lisboa Norte from January 2006 to December 2019. NLR was calculated at admission. The outcomes measured were severe infection at 3 months and one-year mortality. The prognostic ability of the NLR was determined using the receiver operating characteristic (ROC) curve. A cut-off value was defined as that with the highest validity. All variables underwent univariate analysis to determine statistically significant factors that may have outcomes. Only variables which significantly differed were used in the multivariate analysis using the logistic regression method.

RESULTS

We registered 45 cases of AVV. The mean age at diagnosis was 67.5±12.1 years and 23 patients were male. The mean Birmingham Vasculitis Activity Score (BVAS) at presentation was 26.0±10.4. Twenty-nine patients were ANCA-MPO positive, 7 ANCA-PR3 positive and 9 were considered negative ANCA vasculitis. At admission, mean serum creatinine (SCr) was 4.9±2.5mg/dL, erythrocyte sedimentation rate (ESR) was 76.9±33.8mm/h, hemoglobin was 9.5±1.7g/dL, C-reactive protein was 13.2±5.8mg/dL and NLR was 8.5±6.8. Thirty-five patients were treated with cyclophosphamide, eight patients with rituximab for induction therapy. Twenty patients developed severe infection within the first three months after starting induction immunosuppression. In a multivariate analysis, older age (73.6±10.5 vs. 62.6±11.3, p=0.002, adjusted OR 1.08 [95% CI 1.01-1.16], p=0.035) and higher NLR (11.9±7.4 vs. 5.9±5.0, p=0.002, adjusted OR 1.14 [95% CI 1.01-1.29], p=0.035) were predictors of severe infection at 3 months. NLR ≥4.04 predicted severe infection at 3 months with a sensitivity of 95% and specificity of 52% and the AUROC curve was 0.0794 (95% CI 0.647-0.900). Nine patients died within the first year. Severe infection at 3 months was independently associated with mortality within the first year (OR 6.19 [95% CI 1.12-34.32], p=0.037).

CONCLUSIONS

NLR at diagnosis was an independent predictor of severe infection within the first 3 months after immunosuppression start, and severe infection within the first three months was consequently correlated with one-year mortality. NLR is an easily calculated and low-cost laboratory inflammation biomarker and can prove useful in identifying AAV patients at risk of infection and poorer prognosis.

Prevalence of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis and spatial association with quarries in a French Northeast region

OBJECTIVE

Silica is one of the strongest environmental substances linked with autoimmunity. The aim of this study was to assess the prevalence of granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and renal limited vasculitis (RLV) in a French northeast region, and their geospatial association with quarries.

METHODS

Potential ANCA-Associated Vasculitis (AAV) cases were identified using three sources: hospital records, immunology laboratories and the National Health Insurance System. Patients who resided in Alsace on January 1, 2016 and fulfilled ACR AAV criteria or Chapel Hill Consensus Conference 2012 definition were included. Incomplete case ascertainment was corrected using capture-recapture analysis. The spatial association between the number of cases and quarries in each administrative entity was assessed using geographical weighted regression (GWR).

RESULTS

From 910 potential AAV cases, we identified 185 patients meeting inclusion criteria: 120 GPA, 35 MPA, 30 RLV. The number of cases missed by any source was 6.4 (95%CI 3.6-11.5). Accordingly, the 2016 estimated prevalence in Alsace was 65.5 cases per million inhabitants (95%CI 47.3-93.0) for GPA, 19.1 (95%CI 11.3-34.3) for MPA, and 16.8 (95%CI 8.7-35.2) for RLV. The risk of AAV was significantly increased in communes with quarries (OR: 2.51 [95%CI: 1.66-3.80]) and GWR revealed a significant spatial association between quarries and GPA cases (p = 0.039), and, regarding ANCA serotype, between quarries and both PR3-AAV (p = 0.04) and MPO-AAV (p = 0.03)."

CONCLUSION

In a region with a high density of quarries, the spatial association of AAV with quarries supports the role of silica as a specific environmental factor.

Evolving Challenges in Diagnosis of Renal Vasculitis

Renal-limited vasculitis is a rare anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis that presents only with a renal manifestation in the absence of other organs involvement. In this report, a 50-year-old female presented with nonspecific symptoms and anemia, who was subsequently discovered to have renal-limited vasculitis. After receiving a combination of steroid and immunosuppressive therapy, she recovered uneventfully without further relapse. A wide range of nonspecific presenting symptoms and the insidious nature of renal disease often delay in early recognition of renal-limited vasculitis. Keeping a lower threshold of initiating vasculitis workup helps detect the earlier diagnosis which is crucial in management with improved renal outcome.

The neutrophil-to-lymphocyte ratio as a marker of vasculitis activity, severe infection and mortality in anca-associated vasculitis: A retrospective study

INTRODUCTION

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a multisystemic disease. Despite the improvement in mortality rate since the introduction of immunosuppression, long-term prognosis is still uncertain not only because of the disease activity but also due to treatment associated adverse effects. The neutrophil-to-lymphocyte ratio (NLR) has been demonstrated as an inflammatory marker in multiple settings. In this study, we aimed to investigate the prognostic ability of the NLR in AAV patients.

METHODS

We conducted a retrospective analysis of the clinical records of all adult patients with AVV admitted to the Nephrology and Renal Transplantation Department of Centro Hospitalar Universitário Lisboa Norte from January 2006 to December 2019. NLR was calculated at admission. The outcomes measured were severe infection at 3 months and one-year mortality. The prognostic ability of the NLR was determined using the receiver operating characteristic (ROC) curve. A cut-off value was defined as that with the highest validity. All variables underwent univariate analysis to determine statistically significant factors that may have outcomes. Only variables which significantly differed were used in the multivariate analysis using the logistic regression method.

RESULTS

We registered 45 cases of AVV. The mean age at diagnosis was 67.5±12.1 years and 23 patients were male. The mean Birmingham Vasculitis Activity Score (BVAS) at presentation was 26.0±10.4. Twenty-nine patients were ANCA-MPO positive, 7 ANCA-PR3 positive and 9 were considered negative ANCA vasculitis. At admission, mean serum creatinine (SCr) was 4.9±2.5mg/dL, erythrocyte sedimentation rate (ESR) was 76.9±33.8mm/h, hemoglobin was 9.5±1.7g/dL, C-reactive protein was 13.2±5.8mg/dL and NLR was 8.5±6.8. Thirty-five patients were treated with cyclophosphamide, eight patients with rituximab for induction therapy. Twenty patients developed severe infection within the first three months after starting induction immunosuppression. In a multivariate analysis, older age (73.6±10.5 vs. 62.6±11.3, p=0.002, adjusted OR 1.08 [95% CI 1.01-1.16], p=0.035) and higher NLR (11.9±7.4 vs. 5.9±5.0, p=0.002, adjusted OR 1.14 [95% CI 1.01-1.29], p=0.035) were predictors of severe infection at 3 months. NLR ≥4.04 predicted severe infection at 3 months with a sensitivity of 95% and specificity of 52% and the AUROC curve was 0.0794 (95% CI 0.647-0.900). Nine patients died within the first year. Severe infection at 3 months was independently associated with mortality within the first year (OR 6.19 [95% CI 1.12-34.32], p=0.037).

CONCLUSIONS

NLR at diagnosis was an independent predictor of severe infection within the first 3 months after immunosuppression start, and severe infection within the first three months was consequently correlated with one-year mortality. NLR is an easily calculated and low-cost laboratory inflammation biomarker and can prove useful in identifying AAV patients at risk of infection and poorer prognosis.

Infection-induced myeloperoxidase specific antineutrophil cytoplasmic antibody (MPO-ANCA) associated vasculitis: A systematic review

BACKGROUND

We conducted a systematic review to identify cases of infection-induced anti-myeloperoxidase (MPO) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

PubMed/Medline databases were searched from inception to July of 2020, according to PRISMA guidelines.

RESULTS

Among the 618 abstracts identified, 18 articles describing 23 patients (60.9% female, mean age 50.5 years) were included. Median time between infection and vasculitis development was 3 months. Five (21.7%) patients expired during follow-up. Vasculitis regressed after the resolution of infection in 12/23 (52.2%). ANCA titers decreased significantly on follow-up in 14/16 patients and in all survivors in which they were measured. Pathogens reported included Mycobacterium spp., Coccidioides spp., Rickettsia rickettsii, Staphylococcus spp., EBV, CMV and Dengue virus.

CONCLUSIONS

MPO-AAV can occur after infection and may regress after its resolution. Infection should be considered in cases of MPO-AAV, as immunosuppressive treatment can have catastrophic results if the infection is not adequately treated.

Aortic Involvement in Antineutrophil Cytoplasmic Antibodies Vasculitis, a Coincidence or a Real Association?

Antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) is a type of small-vessel vasculitis. It is unusual for ANCA to involve aorta. However, multiple cases have been found where ANCA involved large vessels, particularly the aorta. Among vasculitides, aortic vasculitis is a part of Takayasu arteritis (TAK). In this review article, we tried to find the mechanism behind the aortic involvement in AAV. PubMed was used as a primary search engine, and all the available cases of aortic, as well as large-vessel involvement in ANCA-associated vasculitis, were thoroughly reviewed. Very limited data was available that could provide the mechanism behind this involvement. It is observed that ANCA-associated aortitis is more common in immunocompromised people; however, cases in previously healthy individuals have also been found. Pathogenesis of ANCA-related aortitis is different from Takayasu arteritis and is more close to ANCA-associated small vasculitis. ANCA-related aortitis involves the aorta through the same mechanism as it uses to involve small vessels. This rare manifestation of ANCA-associated vasculitis could be life-threatening but has a good prognosis if timely diagnosed and treated. ANCA-associated vasculitis must be considered as a differential diagnosis while treating a case of aortitis. We believe that there is a need to revise the classification of different types of vasculitides, and physicians should be aware of the possible overlap between different forms of vasculitides.

Distinct HLA and non-HLA associations in different subtypes of ANCA-associated vasculitides in North India

AIM

Antineutrophil cytoplasmic antibody-associated vasculitis (AAV) is an autoimmune disease characterized by necrotizing small vessel vasculitis that can affect various organs and present multiple symptoms. Susceptibility to AAV is multifactorial and most likely caused by an amalgamation of genetic and environmental factors. The aim of the present study was to explore the distribution of human leukocyte antigen (HLA)-DRB1/DQB1, protein tyrosine phosphatase non-receptor type 22 (PTPN22) and cytotoxic T-Lymphocyte-associated protein 4 (CTLA-4) polymorphisms in North Indian AAV patients and their associations with clinical and pathological characteristics associated with the disease.

METHODS

A total of 150 AAV patients and 150 healthy controls were recruited. The clinical classification showed 128 as granulomatosis with polyangiitis (GPA) and 21 as microscopic polyangiitis. Only 1 case of eosinophilic granulomatosis with polyangiitis was encountered, which was excluded from analysis. HLA-DRB1/DQB1 alleles were determined by polymerase chain reaction-sequence-specific primer (PCR-SSP) method and single nucleotide variant genotyping for CTLA-4 and PTPN22 was done by simple probe-based SNP arrays.

RESULTS

A significant predispositional association of DRB1*03 and DQB1*02 alleles, were confirmed in proteinase 3 (PR3)-AAV patients, whereas DRB1*10, DRB1*14 and DQB1*05 were protective alleles in AAV, PR3-AAV and GPA patients. GG genotype of CTLA-4 + 49A/G was increased in patients as compared to controls and showed an association with AAV, PR3-AAV and GPA patients.

CONCLUSION

The study indicated strong genetic associations were linked with PR3 antineutrophil cytoplasmic antibody specificity and it appears that PR3-AAV and MPO-AAV have distinct genetic backgrounds.

Proteinase-3 and myeloperoxidase serotype in relation to demographic factors and geographic distribution in anti-neutrophil cytoplasmic antibody-associated glomerulonephritis

Background

In anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis, antigen specificity varies between myeloperoxidase (MPO) and proteinase 3 (PR3). This has been reported to vary in relation to age, gender, geography and extrarenal manifestations. However, studies are difficult to compare as criteria for inclusion vary. The aim of this study was to investigate the relationship between ANCA serotype, latitude, ultraviolet (UV) radiation levels, age, gender and renal function at diagnosis in a large study with uniform inclusion criteria.

Methods

Patients with biopsy-proven ANCA-associated glomerulonephritis were identified from regional or nationwide registries in 14 centres in Norway, Sweden, the UK, the Czech Republic, Croatia, Italy and the USA during the period 2000-13. UV radiation levels for 2000-13 in Europe were obtained from the Swedish Meteorological and Hydrological Institute.

Results

A total of 1408 patients (45.2% PR3-ANCA) were included in the study. In univariable analysis, PR3-ANCA was significantly associated with male gender {odds ratio [OR] 2.12 [95% confidence interval (CI) 1.71-2.62]}, younger age [OR per year 0.97 (95% CI 0.96-0.98)] and higher glomerular filtration rate [OR per mL/min 1.01 (95% CI 1.01-1.02); P < 0.001] at diagnosis but not with latitude or UV radiation. In multivariable logistic regression analysis, latitude and UV radiation also became significant, with higher odds for PR3-ANCA positivity at northern latitudes/lower UV radiation levels. However, the latitudinal difference in MPO:PR3 ratio is smaller than differences previously reported concerning microscopic polyangiitis and granulomatosis with polyangiitis.

Conclusions

The ratio between PR3-ANCA and MPO-ANCA varies in glomerulonephritis with respect to age, gender, renal function and geographic latitude/UV radiation levels.

Evaluation of PR3-ANCA Status After Rituximab for ANCA-Associated Vasculitis

INTRODUCTION

The value of antineutrophil cytoplasmic antibody (ANCA) measurements among patients with an established diagnosis of ANCA-associated vasculitis (AAV) to assess disease activity or predict relapse remains controversial, but recent evidence suggests a possible role for rituximab-treated patients.

PATIENTS AND METHODS

All patients with active vasculitis and positive proteinase 3 (PR3)-ANCA who were starting a 2-year treatment course of rituximab for induction of remission at Addenbrooke's Hospital between January 2011 and January 2016 were included in this study. Common department practice consists of 6 g of rituximab given over 2 years, concomitant corticosteroids (0.5-1.0 mg/kg) with rapid taper over 3 months, and cessation of oral maintenance immunosuppressive agents at time of first rituximab dose. Clinical and laboratory data were collected retrospectively using electronic patient records.

RESULTS

Fifty-seven patients with current PR3-ANCA positivity were included in the analysis. Median follow-up was 59 months. PR3-ANCA negativity was achieved in 25 patients (44%) with a median time of 14 months. Clinical remission was achieved in 53 patients (93%) with a median time of 3 months. Among the 53 patients who achieved remission during follow-up, 24 (45%) relapsed with a median time to relapse of 36 months from remission. Both PR3-ANCA-negative status and 50% reduction in PR3-ANCA from baseline (as time-varying covariates) were significantly associated with a longer time to relapse (PR3-ANCA-negative status: hazards ratio, 0.08 [95% confidence interval, 0.01-0.63, p = 0.016]; 50% reduction in PR3-ANCA: hazards ratio, 0.25 [95% confidence interval, 0.18-0.99, p = 0.046]).

CONCLUSIONS

Achieving and maintaining PR3-ANCA negativity after rituximab was associated with longer-lasting remission.

Heightened Immune Response to Presumed Loxosceles reclusa Envenomation

Loxoscelism is a systemic inflammatory reaction in response to a brown recluse spider bite (BRSB). In this case we describe a patient with a heightened inflammatory response to a presumed BRSB, with Coomb's positive hemolysis, cytoplasmic antineutrophil cytoplasmic antibody (cANCA) vasculitis, and features of hemophagocytic lymphohistiocytosis (HLH). A 24-y-old female presented with sudden pain and swelling to her lower back, nausea, fever, and tachycardia after a presumed BRSB. Hemolysis began on hospital day 3 (15.9 g·dL^-1) with a nadir on hospital day 5 (6.3 g·dL^-1). She had an lactate dehydrogenase of 1415 U·L^-1, ferritin of 15534 ng·mL^-1, persistent fever, and signs of bone marrow suppression despite hemolysis, with thrombocytopenia (100,000 μL^-1) and an inadequate reticulocyte response (1.7%) suggestive of HLH. The patient's blood was Coomb's and cANCA/antiproteinase 3 positive. She had signs of toxin-induced vasculitis, with respiratory failure requiring bilevel positive airway pressure, radiographs with bilateral pulmonary infiltrates, and a desquamating rash. She received 6 U of packed red blood cells, furosemide for pleural and pericardial effusions, antibiotics, and symptomatic treatment during the acute phase of her illness. Hemolysis improved without glucocorticoids by hospital day 6. The patient demonstrated a dysregulated immunologic and complement-mediated response to the presumed BRSB. The triad of Coomb's positive hemolysis, cANCA vasculitis, and HLH-like reaction associated with a presumed BRSB is described for the first time in the literature and brings up questions for future research regarding the role of immune modulators and complement inhibitors in the treatment of severe loxoscelism as well as the genetic factors that predispose certain individuals to such reactions.

Silica Exposure Differentially Modulates Autoimmunity in Lupus Strains and Autoantibody Transgenic Mice

Inhalational exposure to crystalline silica is linked to several debilitating systemic autoimmune diseases characterized by a prominent humoral immune component, but the mechanisms by which silica induces autoantibodies is poorly understood. To better understand how silica lung exposure breaks B cell tolerance and unleashes autoreactive B cells, we exposed both wildtype mice of healthy C57BL/6 and lupus-prone BXSB, MRL, and NZB strains and mice carrying an autoantibody transgene on each of these backgrounds to instilled silica or vehicle and monitored lung injury, autoimmunity, and B cell fate. Silica exposure induced lung damage and pulmonary lymphoid aggregates in all strains, including in genetically diverse backgrounds and in autoantibody transgenic models. In wildtype mice strain differences were observed in specificity of autoantibodies and site of enhanced autoantibody production, consistent with genetic modulation of the autoimmune response to silica. The unique autoantibody transgene reporter system permitted the in vivo fate of autoreactive B cells and tolerance mechanisms to be tracked directly, and demonstrated the presence of transgenic B cells and antibody in pulmonary lymphoid aggregates and bronchoalveolar lavage fluid, respectively, as well as in spleen and serum. Nonetheless, B cell enumeration and transgenic antibody quantitation indicated that B cell deletion and anergy were intact in the different genetic backgrounds. Thus, silica exposure sufficient to induce substantial lung immunopathology did not overtly disrupt central B cell tolerance, even when superimposed on autoimmune genetic susceptibility. This suggests that silica exposure subverts tolerance at alternative checkpoints, such as regulatory cells or follicle entry, or requires additional interactions or co-exposures to induce loss of tolerance. This possibility is supported by results of differentiation assays that demonstrated transgenic autoantibodies in supernatants of Toll-like receptor (TLR)7/TLR9-stimulated splenocytes harvested from silica-exposed, but not vehicle-exposed, C57BL/6 mice. This suggests that lung injury induced by silica exposure has systemic effects that subtly alter autoreactive B cell regulation, possibly modulating B cell anergy, and that can be unmasked by superimposed exposure to TLR ligands or other immunostimulants.

Vaccine: friend or foe? Double seropositive vasculitis following influenza vaccination

Administration of the influenza vaccine has been associated with development of several autoimmune phenomena. We describe the case of a 72-year-old male who developed double seropositive vasculitis following seasonal influenza vaccination. On presentation, he was positive for both myeloperoxidase anti-neutrophil cytoplasmic antibody and anti-glomerular basement membrane antibody. He had stage three acute kidney injury requiring dialysis and was treated with methylprednisolone, intravenous cyclophosphamide and plasma exchange. He was also noted to have an incidental seven centimetre abdominal aortic aneurysm. He achieved remission with recovery in renal function and became haemodialysis independent. We hypothesize that the temporal relationship between influenza vaccination and double seropositive vasculitis directly triggered a systemic immune response in a susceptible patient, although a causal relationship cannot be proved. To the best of our knowledge, this is the first case of double seropositive vasculitis occurring in close temporal association with seasonal influenza vaccination.

Biomarkers in Vasculitides of the Nervous System

Besides being affected by the rare and severe primary angiitis of the central nervous system (PACNS) the nervous system is also affected by primary systemic vasculitides (PSV). In contrast to PACNS, PSV affect not only the central but also the peripheral nervous system, resulting in a large array of potential symptoms. Given the high burden of disease, difficulties in distinguishing between differential diagnoses, and incomplete pathophysiological insights, there is an urgent need for additional precise diagnostic tools to enable an earlier diagnosis and initiation of effective treatments. Methods available to date, such as inflammatory markers, antibodies, cerebrospinal fluid (CSF) analysis, imaging, and biopsy, turn out to be insufficient to meet all current challenges. We highlight the use of biomarkers as an approach to extend current knowledge and, ultimately, improve patient management. Biomarkers are considered to be useful for disease diagnosis and monitoring, for predicting response to treatment, and for prognosis in clinical practice, as well as for establishing outcome parameters in clinical trials. In this article, we review the recent literature on biomarkers which have been applied in the context of different types of nervous system vasculitides including PACNS, giant-cell arteritis, Takayasu's arteritis, polyarteritis nodosa, ANCA (anti-neutrophil cytoplasm antibody)-associated vasculitides, cryoglobulinemic vasculitis, IgA vasculitis, and Behçet's disease. Overall, the majority of biomarkers is not specific for vasculitides of the nervous system.

Chronic kidney disease, Queensland: Profile of patients with chronic kidney disease from regional Queensland, Australia: A registry report

BACKGROUND

Chronic kidney disease, Queensland (CKD.QLD) is a multidisciplinary, collaborative research platform for CKD in Queensland. Most public renal services contribute towards the CKD Registry, including Toowoomba Hospital, which is a referral hospital for Darling Downs Health serving a largely regional population in Queensland. We aim to present the profile of the CKD cohort recruited to the CKD.QLD Registry from Toowoomba Hospital, the first comprehensive report on a pre-dialysis population from regional Australia.

METHODS

Study subjects were patients in the Darling Downs Health Service who consented to be included in the CKD.QLD registry from June 2011 to December 2016. Those who were on renal replacement therapy (RRT) were excluded. Patients were followed until date of RRT, death, discharge or loss to follow up or a censor date of 30th June 2017.

RESULTS

Overall 1051 subjects, representing 13% of all CKD.QLD Registry patients gave consent of whom, 42.7% were ≥70 years of age. The mean age was 63.8 ± 15.1 years (median age 67 years) with male predominance (55.4%). The majority were born in Australia (86.4%). Aboriginal and Torre Strait Islanders (A&TSI) constituted 9.6% of the cohort. The predominant CKD stages were 3b (28.9%) and 4 (27.7%). Hypertension and diabetes were noted in 91% and 44% of subjects, respectively. Diabetic nephropathy was the leading cause of CKD (26.7%) followed by renovascular disease (17.3%) and glomerulonephritis (14.8%). In 12%, the diagnosis was uncertain. Major co-morbidities included coronary artery disease (24.7%) chronic lung disease (14.8%), cerebrovascular disease (11.6%) and peripheral vascular disease (8.9%). Non-vascular co-morbidities included arthritis (24.6%), gout (23.6%) and gastro-oesophageal reflux disease (19%). The multi-morbidity profile was differed by gender, diabetic status and age. Over a follow-up period upto 72 months, 93 (8.8%) started RRT and 175 (16.6%) died. Of those 82% died without RRT and 18% died after RRT.

CONCLUSION

This CKD Registry cohort from regional Queensland consisted mainly of older Caucasians with male predominance. A&TSI patients were overrepresented compared to the overall population. A significant proportion had cardio-vascular disease and multiple co-morbidities which differed by gender, diabetic status and age. This report provides valuable data for health services planning and delivery in regional Queensland.

Genetic Associations and Environmental Exposures in the Aetiopathogenesis of Anti-Neutrophil Cytoplasmic Antibody- Associated Vasculitis: An Updated Review

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) represents a heterogeneous group of rare diseases characterised by necrotising inflammation of the small blood vessels and the presence of ANCA with specificity for proteinase-3 or myeloperoxidase. Genetic susceptibility along with malignancy, drug exposure, and environmental exposures to infectious agents and silica are involved in disease progression. To date, growing evidence has revealed that ANCA specificity defines homogeneous groups of patients more effectively than clinical diagnosis, since proteinase-3 ANCA and myeloperoxidase-ANCA are linked with different genetic backgrounds and epidemiologies. This review presents current and updated knowledge on the central aetiopathogenic role of genetic associations and environmental exposures in AAV; discusses the main mechanisms of ANCA immunogenesis; and highlights the value of ANCA specificity for future classification criteria.

Recent advances in understanding of the pathogenesis of ANCA-associated vasculitis

Anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV) are rare systemic autoimmune diseases characterised by inflammation of small blood vessels. Recent developments have been made in our understanding of the pathogenesis of these diseases, including the pathogenic role of ANCA, neutrophils and monocytes as mediators of injury, dysregulation of the complement system, and the role of T and B cells. Current treatment strategies for AAV are based on broad immunosuppression, which may have significant side effects. Advances in understanding of the pathogenesis of disease have led to the identification of new therapeutic targets which may lead to treatment protocols with less-toxic side effects. The aim of this review is to summarise current information and recent advances in understanding of the pathogenesis of AAV.

Novel insights into the aetiology of granulomatosis with polyangiitis-a case-control study using the Clinical Practice Research Datalink

Objectives

We aimed to provide insights into the aetiology of granulomatosis with polyangiitis (GPA), by conducting a large case-control study using a general population-based, prospectively collected database of healthcare records.

Methods

We compared all incident cases of GPA in the Clinical Practice Research Datalink 1990-2014, with up to 10 age-, sex- and general practice-matched controls. We identified potential risk factors, recorded numbers of cases and controls exposed to each, and calculated odds ratios (ORs) using conditional logistic regression. Our main analysis excluded data recorded during 1 year before diagnosis, to prevent early symptoms being mistaken for risk factors.

Results

We identified 757 people with GPA and matched 7546 controls. People with GPA were five times more likely to have a previous diagnosis of bronchiectasis (OR = 5.1, 95% CI: 2.7, 9.4; P < 0.0001), and these effects remained stable in diagnoses recorded >5 years prior to diagnosis. People with GPA were two to three times more likely than controls to have previous diagnoses of autoimmune diseases or chronic renal impairment, and these effects also remained stable >5 years prior to diagnosis. People with GPA were more likely to have a diagnosis of pulmonary fibrosis (OR = 5.7, 95% CI: 1.7, 19.5; P = 0.01) and sinus infections (OR = 2.7, 95% CI: 1.8, 4.2; P < 0.0001) recorded in the 3 years before diagnosis, but not before this. We also found former smoking, some medications and higher socio-economic status significantly, but less strongly, associated.

Conclusion

We found novel long-term associations between GPA and pre-existing bronchiectasis and autoimmune diseases.

Delta Neutrophil Index Is Associated with Vasculitis Activity and Risk of Relapse in ANCA-Associated Vasculitis

PURPOSE

Delta neutrophil index (DNI) represents the immature granulocytes count associated with neutrophil-consumption. We investigated whether DNI might be associated with Birmingham vasculitis activity score (BVAS) at diagnosis and could predict relapse during the follow-up in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV).

MATERIALS AND METHODS

We reviewed the medical records of 97 patients having DNI results. Twenty patients had granulomatosis with polyangiitis (GPA), 58 had microscopic polyangiitis (MPA), and 19 had eosinophilic GPA (EGPA). We collected clinical and laboratory data including BVAS, five factor score (FFS), and DNI. The correlation coefficient and cumulative relapse free survival rate were obtained. The optimal cut-off of DNI was extrapolated by calculating the area under the receiver operator characteristic curve.

RESULTS

DNI was significantly related to cross-sectional BVAS. Furthermore, among continuous variables, only DNI could reflect BVAS of GPA and MPA, but not EGPA. Severe AAV was defined as BVAS ≥20 (the highest quartile). At diagnosis, patients having DNI ≥0.65% had a significantly higher risk of severe GPA and MPA than those having not (relative risk 4.255) at diagnosis. During the follow-up, DNI ≥0.65% could predict the higher relapse rate.

CONCLUSION

DNI could reflect BVAS at diagnosis and furthermore, DNI ≥0.65% could not only identify severe AAV at diagnosis, but also predict relapse during the follow-up in patients with GPA and MPA.

MPO-ANCA associated vasculitis with mononeuritis multiplex following influenza vaccination

Background

Although influenza vaccines are generally safe and effective, a variety of autoimmune phenomena have been reported after vaccination over the past years, such as Guillain–Barre syndrome, rheumatoid arthritis, pemphigus vulgaris, psoriasis, giant cell arteritis and anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV).

Case report

We describe the case of a 67-year old man who presented with a myeloperoxidase-ANCA associated vasculitis with renal involvement and mononeuritis multiplex after seasonal influenza vaccination. He was initially treated with intravenous cyclophosphamide and high-dose prednisolone followed by maintenance treatment consisting of azathioprine and prednisolone.

Conclusion

We hypothesize that seasonal influenza vaccination triggered a systemic immune response in a susceptible patient to develop AAV with renal involvement and vasculitic neuropathy. In general, seasonal influenza vaccinations are considered to be safe, however, clinicians should be aware of this rare phenomenon.

HLA-DPB1 as a Risk Factor for Relapse in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: A Cohort Study

OBJECTIVE

The antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) form a group of small-vessel vasculitides with systemic involvement. Although the etiology of AAVs remains largely unknown, both genetic and environmental factors have been implicated. Recently, certain alleles in the HLA-DPB1 region on chromosome 6 were shown to be associated with proteinase 3 (PR3)-ANCA-positive AAV but not with myeloperoxidase (MPO)-ANCA-positive AAV. The aim of this study was to investigate whether different alleles in the HLA-DPB1 region have clinical and/or prognostic implications in AAV.

METHODS

One hundred seventy-four patients with a diagnosis of AAV were recruited at the Maastricht University Medical Centre between 2000 and 2009. Seventeen different HLA-DPB1 alleles were determined using the restriction fragment length polymorphism technique. A validation cohort of 170 AAV patients from the Vasculitis Centre of Luebeck/Bad Bramstedt was included.

RESULTS

In the initial cohort, the distribution of HLA-DPB1 alleles was significantly different between PR3-ANCA-positive compared with MPO-ANCA-positive AAV patients, ANCA-negative AAV patients, and healthy controls. Importantly, HLA-DPB1*04:01 was present in 90% of PR3-ANCA-positive AAV patients compared with 63% of MPO-ANCA-positive AAV patients, 58% of ANCA-negative patients, and 63% of healthy controls. Patients homozygous for HLA-DPB1*04:01 had relapses more often compared with heterozygous patients and noncarrier patients. This association persisted after correction for ANCA subtype and diagnosis. In the validation cohort, patients homozygous for HLA-DPB1*04:01 and those heterozygous for HLA-DPB1*04:01 had relapses more often compared with noncarrier patients. When both patient cohorts were merged (n = 344), homozygous patients relapsed most often, followed by heterozygous patients and noncarrier patients.

CONCLUSION

Carriage of HLA-DPB1*04:01 in patients with AAV is significantly associated with an increased risk of relapse compared with HLA-DPB1*04:01-negative patients, irrespective of ANCA status or clinical AAV entity.

Pathophysiology of ANCA-associated Vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is characterized as inflammation of small-sized to medium-sized blood vessels and encompasses several clinicopathologic entities including granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis, and renal-limited ANCA-associated vasculitis. Over the past several decades, significant progress has been made in understanding the pathophysiology of ANCA-associated vasculitis. Although neutrophils contain a multitude of granular proteins, clinically significant autoantibodies are only recognized against myeloperoxidase and proteinase 3, both of which are present in the azurophilic granules. The propensity to develop these antibodies depends on a variety of predisposing factors such as microbial infection, genetic factors, environmental agents, and therapeutic drugs among others. These factors are usually associated with production of proinflammatory cytokines with capacity to prime the neutrophils. As a result a high proportion of neutrophils in circulation may be primed resulting in exposure of cytoplasmic proteins including myeloperoxidase and proteinase 3 on the surface of the neutrophils. Primed neutrophils are activated by interaction with ANCA in circulation. Activated neutrophils attach to and transmigrate through endothelium and accumulate within the vessel wall. These neutrophils degranulate and produce reactive oxygen radicals and ultimately die, causing tissue injury. Endothelial injury results in leakage of serum proteins and coagulation factors causing fibrinoid necrosis. B cells produce ANCAs, as well as neutrophil abnormalities and imbalances in different T-cell subtypes with excess of Th17, which perpetuate the inflammatory process.

[Skin diseases due to systemic vasculitides and vasculopathies]

Vasculitis and vasculopathy are two distinct disease entities. Each entity comprises a large number of heterogeneous diseases, which can occur alone or associated with autoimmune, infectious or neoplastic diseases. The terms vasculitis and vasculopathy are often falsely used synonymously. A vasculitis initially causes inflammation of the vessel walls that may result in a secondary occlusion. In contrast, a vasculopathy is a primary occlusion of the vascular lumen, which is followed by inflammation after ischemia and ulceration. In most patients the distinction can be made based on the clinical presentation. A clear clinical diagnosis is then followed by targeted serological, histological and imaging procedures to confirm the clinical diagnosis. On this basis a well-founded treatment can be initiated. In the presence of vasculitis an anti-inflammatory therapy is indicated, whereas in the case of vasculopathy, removal of the vascular occlusion is the main focus. This article provides an overview of the various diseases and addresses the pathogenetic and clinical characteristics used to differentiate the individual disease entities. It also provides an insight into the therapy options and prophylaxis.

The influence of the Great East Japan earthquake on microscopic polyangiitis: A retrospective observational study

BACKGROUND

Antineutrophil cytoplasmic antibody-associated vasculitis is triggered by environmental factors, including silica dust exposure. Repeated tsunami waves brought a large volume of silica-containing sludge inland after the Great East Japan earthquake in 2011. We aimed to determine if the serious disaster influenced the clinical features of the microscopic polyangiitis.

METHODS

This is an observational retrospective study conducted in a single institute. A total of 43 patients were included based on the CHCC2012 criteria for microscopic polyangiitis from 2007 to 2015. We used the Poisson regression model to determine the incidence of microscopic polyangiitis within the annual population of the medical district. The participants were selected during a 3-year period from before (N = 13) to after the disaster (N = 20). The differences of parameters and the overall survival between the groups were analyzed.

RESULTS

The incidence of microscopic polyangiitis increased after the disaster (λ = 17.4/million/year [95%CI: 7.66-39.6] before the disaster and λ = 33.1/million/year [17.7-61.7] after the disaster, P = 0.044). A high Birmingham Activity Score was associated with a high incidence of microscopic polyangiitis after the disaster. The overall survival of the patients with microscopic polyangiitis declined significantly after the disaster.

CONCLUSIONS

The Great East Japan earthquake influenced the development of the microscopic polyangiitis in our restricted area. The patients who developed after the disaster had severe symptoms and a high mortality rate.

Galactosylation and Sialylation Levels of IgG Predict Relapse in Patients With PR3-ANCA Associated Vasculitis

OBJECTIVE

The objective of our study is to investigate the Fc glycosylation profiles of both antigen-specific IgG targeted against proteinase 3 (PR3-ANCA) and total IgG as prognostic markers of relapse in patients with Granulomatosis with Polyangiitis (GPA).

METHODS

Seventy-five patients with GPA and a PR3-ANCA rise during follow-up were included, of whom 43 patients relapsed within a median period of 8 (2-16) months. The N-glycan at Asn297 of affinity-purified and denatured total IgG and PR3-ANCA was determined by mass spectrometry of glycopeptides in samples obtained at the time of the PR3-ANCA rise and at the time of the relapse or time-matched during remission.

RESULTS

Patients with total IgG1 exhibiting low galactosylation or low sialylation were highly prone to relapse after an ANCA rise (HR 3.46 [95%-CI 1.73-6.96], p<0.0001 and HR 3.22 [95%-CI 1.52-6.83], p=0.002, respectively). In relapsing patients, total IgG1 galactosylation, sialylation and bisection significantly decreased and fucosylation significantly increased from the time of the PR3-ANCA rise to the relapse (p<0.0001, p=0.0087, p<0.0001 and p=0.0025), while the glycosylation profile remained similar in non-relapsing patients. PR3-ANCA IgG1 galactosylation, sialylation and fucosylation of PR3-ANCA IgG1 decreased in relapsing patients (p=0.0073, p=0.0049 and p=0.0205), but also in non-relapsing patients (p=0.0007, p=0.0114 and p=0.0002), while bisection increased only in non-relapsing patients (p<0.0001).

CONCLUSION

While Fc glycosylation profiles have been associated with clinically manifest autoimmune diseases, in the present study we show that low galactosylation and sialyation in total IgG1 but not PR3-ANCA IgG1 predicts disease reactivation in patients with GPA who experience an ANCA rise during follow-up. We postulate that glycosylation profiles may be useful in pre-emptive therapy studies using ANCA rises as guideline.

Seasonal Influence on the Risk of Relapse at a Rise of Antineutrophil Cytoplasmic Antibodies in Vasculitis Patients with Renal Involvement

Objective.

The objective of this study was to identify risk factors for a relapse at the time of an increase in antineutrophil cytoplasmic antibodies (ANCA) in patients with renal ANCA-associated vasculitis (AAV).

Methods.

All patients between January 2000 and November 2011 with renal AAV having an ANCA rise during remission were included. Differences in time to relapse since the ANCA rise were assessed using a Cox regression model. The level of 25-hydroxy Vitamin D (25(OH)D) was assessed at the ANCA rise and at a subsequent relapse or time-matched during remission.

Results.

Sixty patients had an ANCA rise, of whom 36 patients relapsed. Three risk factors were associated with a relapse at the time of the ANCA increase: previous disease activity not treated with cyclophosphamide or rituximab (HR 3.48, 95% CI 1.60–7.59), an ANCA rise during the fall season (HR 4.37, 95% CI 1.60–11.90), and an extended ANCA rise (HR 3.57, 95% CI 1.50–8.48). Levels of 25(OH)D significantly decreased during followup in relapsing patients, but not in patients who remained in remission (difference −6.3 ± 14.4, p = 0.017 vs 2.7 ± 16.3, p = 0.430).

Conclusion.

ANCA rises occurring during the fall season are more frequently followed by a relapse than ANCA rises occurring during other seasons. Although it is tempting to speculate that decreasing Vitamin D levels following the ANCA rise can be held responsible for the subsequent relapse, this remains to be determined.

Characteristics and prognosis of microscopic polyangiitis with bronchiectasis

BACKGROUND

Major pulmonary manifestations associated with microscopic polyangiitis (MPA) include diffuse alveolar hemorrhage (DAH) and interstitial pneumonia (IP).We previously showed bronchiectasis (BE) was one of the pulmonary complications of MPA. However, clinical features of BE patients with MPA are not fully understood. We investigated the characteristics and prognosis of BE patients with MPA.

METHODS

Forty-five MPA patients were retrospectively studied. The patients were divided into two groups: patients with BE and those without BE.

RESULTS

Thirty-one of 45 patients (69%) had pulmonary involvement including IP (23/45, 51%), BE (7/45, 16%), and DAH (5/45, 11%). There were no differences between the patients with BE versus those without with regard to clinical characteristics and initial treatments. However, the prognosis for patients with BE was better than those without BE during the first year after diagnosis, but it was worse between 1 and 5 years, which was statistically significant. Two BE patients died between 1 and 5 years as a result of pneumonia.

CONCLUSIONS

BE as a complication of MPA might be related to lower mortality in the acute phase and higher mortality in the chronic phase compared to other pulmonary manifestations. More attention to pulmonary infection is needed for patients with BE during the chronic phase.

Incidence of Malignancy Prior to Antineutrophil Cytoplasmic Antibody–associated Vasculitis Compared to the General Population

Objective.

Previous studies have reported an increased malignancy risk preceding antineutrophil cytoplasmic antibody–associated vasculitis (AAV), suggesting common pathogenic pathways in these 2 entities. However, the study results were conflicting and often limited to patients with granulomatosis with polyangiitis (GPA). Here, we study the malignancy risk prior to AAV diagnosis [either GPA or microscopic polyangiitis (MPA)] to elaborate on the putative association between malignancy and AAV.

Methods.

A total of 203 patients were selected for the current study. Malignancies prior to AAV diagnosis were identified using a nationwide pathology database, and their occurrence was verified by reviewing the medical files of 145 patients (71.4%). The malignancy incidence was compared to the general population by calculation of standardized incidence ratios (SIR), matching for sex, age, and time period. SIR were calculated for 2 intervals: < 2 years and ≥ 2 years prior to AAV diagnosis. Separate analyses were performed for GPA and MPA.

Results.

The overall risk for malignancy prior to AAV diagnosis was similar to that of the general population (SIR 0.96, 95% CI 0.55–1.57), as was true when risks were analyzed by malignancy type, including skin, bladder, kidney, lung, stomach, rectum, and uterus (SIR ranged from 1.64 to 4.14). We found no significant difference in malignancy risk between patients with GPA and MPA.

Conclusion.

Our findings do not support the hypothesis that preceding malignancies and AAV have a causal relationship or shared pathogenic pathways.

Anti-neutrophil cytoplasmic antibodies in cholesterol embolism: A case report and literature review

Cholesterol embolism is a multisystemic disorder with clinical manifestations that resemble vasculitis. Anti-neutrophil cytoplasmic antibodies (ANCA) are a defining feature of ANCA-associated vasculitis, and the presence of ANCA in cholesterol embolism complicates its differential diagnosis and treatment. At present, the role of ANCA in cholesterol embolism remains unclear and no effective treatment is currently available. The present study reports the case of an Asian male who presented with spontaneous cholesterol embolism with proteinase 3 (PR3)-specific ANCA, subacute interstitial nephritis and late-developing skin lesions. The 69-year-old patient was admitted to The First Affiliated Hospital of Xiamen University (Xiamen, China) complaining of chest tightness, fatigue, progressive renal failure and refractory hypertension. In addition, transient eosinophilia was detected. Following immunosuppressive therapy with steroids and cyclophosphamide for 6 months, hemodialysis treatment was initiated. Skin lesions appeared at >1 month following hemodialysis initiation; however, they were gradually improved following treatment with atorvastatin and anti-platelet aggregation therapy for 5 months. The patient was maintained on hemodialysis for ~2 years and exhibited general good health at the most recent follow-up. In addition, 11 cases of cholesterol embolism associated with ANCA reported in the literature were discussed in the present study.

Recent advances in anti-neutrophil cytoplasmic antibody-associated vasculitis

Anti-neutrophil cytoplasmic antibody-associated vasculitis is an uncommon inflammatory disease of small to medium-sized vessels that frequently presents with rapidly progressive glomerulonephritis and renal failure though it can affect any organ system. If untreated, the vast majority of patients will die within a year. Current treatments improve prognosis but affected patients remain at a substantially higher risk of death and adverse outcomes. We review the classification of the disease, our understanding of the pathogenesis and epidemiology, and propose future directions for research. We also evaluate the evidence supporting established treatment regimens and the progress of clinical trials for newer treatments to inform the design of future studies.

Genetic variants in ANCA-associated vasculitis: a meta-analysis

BACKGROUND

Genetic factors may influence the pathogenic pathways leading to antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). We performed a meta-analysis to determine the genetic variants most likely associated with AAV and investigated whether diagnostic and serological subtypes within AAV have distinct genetic backgrounds.

METHODS

Studies investigating the association between genetic variants and AAV in humans were searched in PubMed, EMBASE and Web of Science. All variants investigated in at least two studies were selected. Subsequently, all studies assessing these variants were included in this meta-analysis. Additionally, data on these variants from the largest genome-wide association studies in AAV were included to increase the validity of this meta-analysis.

RESULTS

The literature search yielded 5180 articles. 62 articles investigating 140 genetic variants were included, 33 of which were associated with AAV in a meta-analysis. These genetic variants were in or near the following genes: CD226, CTLA-4, FCGR2A, HLA-B, HLA-DP, HLA-DQ, HLA-DR, HSD17B8, IRF5, PTPN22, RING1/RXRB, RXRB, STAT4, SERPINA1 and TLR9. Moreover, we identified genetic distinctions between granulomatosis with polyangiitis and microscopic polyangiitis and between proteinase 3 ANCA vasculitis and myeloperoxidase ANCA vasculitis. In 76% of the genetic variants, subdivision based on ANCA serotype resulted in higher ORs than subdivision based on clinical diagnosis.

CONCLUSIONS

This meta-analysis identified 33 genetic variants associated with AAV, supporting a role for alpha-1-antitrypsin, the major histocompatibility complex system, and several distinct inflammatory processes in AAV pathogenesis. Our results indicate that subdivision of AAV based on ANCA serotype has a stronger genetic basis than subdivision based on clinical diagnosis.

Classification, epidemiology and clinical subgrouping of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis

It is now 25 years since the first European studies on vasculitis--the anti-neutrophil cytoplasmic antibody (ANCA) standardization project. Over that period of time, there have been major developments in the classification of the vasculitides, which has permitted the conduct of high-quality epidemiology studies. Studying the epidemiology of rare diseases such as the ANCA-associated vasculitides (AAV) poses considerable challenges to epidemiologists. The first is the need for a clear definition of a case with good differentiation from similar disorders. The second is case capture. The vasculitides are rare, and therefore, a large population is required to determine the incidence and prevalence, and this poses questions of feasibility. A large population increases the risk of incomplete case detection but permits a reasonable number of cases to be collected in a practicable time frame, whereas a smaller population requires a much longer time frame to collect the necessary cases, which may also not be feasible. Statistical methods of capture-recapture analysis enable estimates to be made of the number of missing cases. The third is case ascertainment. The AAV are virtually always managed in secondary care, and therefore, hospital-based case ascertainment may be appropriate. Fourthly, the rarity of the conditions makes prospective case-control studies investigating risk factors difficult to conduct because the population size required to achieve statistical confidence is in excess of that which is readily available. Thus, much of the data on risk factors are derived from retrospective studies with inherent potential bias.

Proteinase 3-ANCA Vasculitis versus Myeloperoxidase-ANCA Vasculitis

In patients with GN or vasculitis, ANCAs are directed against proteinase 3 (PR3) or myeloperoxidase (MPO). The differences between PR3-ANCA-associated vasculitis (AAV) and MPO-AAV described in the past have been supplemented during the last decade. In this review, we discuss the differences between these two small-vessel vasculitides, focusing especially on possible etiologic and pathophysiologic differences. PR3-AAV is more common in northern parts of the world, whereas MPO-AAV is more common in southern regions of Europe, Asia, and the Pacific, with the exception of New Zealand and Australia. A genetic contribution has been extensively studied, and there is a high prevalence of the HLA-DPB1*04:01 allele in patients with PR3-AAV as opposed to patients with MPO-AAV and/or healthy controls. Histologically, MPO-AAV and PR3-AAV are similar but show qualitative differences when analyzed carefully. Clinically, both serotypes are difficult to distinguish, but quantitative differences are present. More organs are affected in PR3-AAV, whereas renal limited vasculitis occurs more often in patients with MPO-AAV. For future clinical trials, we advocate classifying patients by ANCA serotype as opposed to the traditional disease type classification.

A case of granulomatosis with polyangiitis preceded by subacute thyroiditis

Granulomatosis with polyangiitis can be a complication of thyroid disease, not only autoimmune disease but also subacute thyroiditis.

Long-term safety and efficacy of rituximab in 7 Japanese patients with ANCA-associated vasculitis

OBJECTIVES

The safety and efficacy of rituximab were examined in a multicenter open-label pilot study in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in Japan.

METHODS

Patients with refractory AAV were administered a rituximab infusion at a weekly dose of 375 mg/m(2) for 4 weeks. All patients also received oral daily prednisolone. The primary outcome was complete remission, which was defined as a Birmingham Vasculitis Activity Score (BVAS) of 0 or 1.

RESULTS

The mean age of the 7 patients was 57 (range, 34-71) years. The mean follow-up period after rituximab treatment was 62.9 (range, 4.8-81) months. The mean BVAS at entry was 16.7 (range, 2-34). Complete remission occurred in all cases, except in 1 case in which the patient died, with a significant decline in BVAS from baseline at 12 months after initiation of rituximab. Rituximab reduced granulomatous orbital involvement in a patient with granulomatosis with polyangiitis. Relapse occurred in five patients. Adverse events included de novo hepatitis B in one patient, cancer (hepatocellular carcinoma and prostate cancer) in two patients, and transient visual disturbance, atypical mycobacterial infection, urinary tract infection, sepsis, and cytomegalovirus infection. Two patients died due to recurrent infections and airway obstruction, caused by an AAV lesion.

CONCLUSIONS

Rituximab had a beneficial effect on refractory AAV in Japanese patients, but several adverse effects occurred during rituximab treatment.

ANCA as a predictor of relapse: useful in patients with renal involvement but not in patients with nonrenal disease

The value of measuring ANCA during follow-up to predict a relapse is controversial. On the basis of recently obtained pathophysiologic insights, we postulated that measuring ANCA is useful in patients with renal involvement but is less valuable in patients with nonrenal disease. One hundred sixty-six consecutive patients with ANCA-associated vasculitis, positive for either proteinase 3 (PR3)-ANCA or myeloperoxidase (MPO)-ANCA, were included in our study, followed at regular intervals, and tested for PR3-ANCA and MPO-ANCA. In this cohort, 104 patients had renal involvement (72 with PR3-ANCA, 32 with MPO-ANCA) and 62 patients had nonrenal disease (36 with PR3-ANCA, 26 with MPO-ANCA). During an average (±SD) follow-up of 49±33 months and 18±14 ANCA measurements, 89 ANCA rises and 74 relapses were recorded. ANCA rises correlated with relapses in patients who presented with renal involvement (hazard ratio [HR], 11.09; 95% confidence interval [95% CI], 5.01 to 24.55), but in comparison, associated only weakly with relapses in patients who presented with nonrenal disease (HR, 2.79; 95% CI, 1.30 to 5.98). In conclusion, longitudinal ANCA measurements may be useful in patients with renal involvement but is less valuable in patients with nonrenal disease.

T cell-macrophage interactions and granuloma formation in vasculitis

Granuloma formation, bringing into close proximity highly activated macrophages and T cells, is a typical event in inflammatory blood vessel diseases, and is noted in the name of several of the vasculitides. It is not known whether specific properties of the microenvironment in the blood vessel wall or the immediate surroundings of blood vessels contribute to granuloma formation and, in some cases, generation of multinucleated giant cells. Granulomas provide a specialized niche to optimize macrophage-T cell interactions, strongly activating both cell types. This is mirrored by the intensity of the systemic inflammation encountered in patients with vasculitis, often presenting with malaise, weight loss, fever, and strongly upregulated acute phase responses. As a sophisticated and highly organized structure, granulomas can serve as an ideal site to induce differentiation and maturation of T cells. The granulomas possibly seed aberrant Th1 and Th17 cells into the circulation, which are known to be the main pathogenic cells in vasculitis. Through the induction of memory T cells, aberrant innate immune responses can imprint the host immune system for decades to come and promote chronicity of the disease process. Improved understanding of T cell-macrophage interactions will redefine pathogenic models in the vasculitides and provide new avenues for immunomodulatory therapy.

[Wegener's granulomatosis]

Wegener's granulomatosis is a necrotizing inflammation of small and medium size vessels with granuloma formation. It is a very heterogeneous disease in respect of severity and clinical manifestation. While it can be a rapidly progressive disease with fatal ending, there are forms limited only to one organ. Diagnosis is supported by the positivity of anti-neutrophil cytoplasmatic antibody and the presence of the typical histological findings. Unfortunately, these examinations cannot confirm clinical suspicion relatively frequently. In addition, there may be only symptoms related to one single organ for a long time at the beginning of the disease and, therefore, one have to be aware of the clinical signs and symptoms of the different organ systems. This may allow us to make an early diagnosis and start treatment in time.