CD36 regulates macrophage and endothelial cell activation and multinucleate giant cell formation in anti neutrophil cytoplasm antibody vasculitis.

OBJECTIVE: To investigate CD36 in ANCA-associated vasculitis (AAV), a condition characterized by monocyte/macrophage activation and vascular damage. METHODS: CD36 expression was assessed in AAV patients and healthy controls (HC). The impact of palmitic acid (PA) stimulation on multinucleate giant cell (MNGC) formation, macrophage, and endothelial cell activation, with or without CD36 knockdown, was examined. RESULTS: CD36 was overexpressed on AAV patients' monocytes compared to HC, regardless of disease activity. AAV patients exhibited elevated soluble CD36 levels in serum and plasma and PR3-ANCA patients' monocytes demonstrated increased MNGC formation following PA stimulation compared to HC. PA stimulation of macrophages or endothelial cells resulted in heightened CD36 expression, cell activation, increased macrophage migration inhibitory factor (MIF) production, and c-Myc expression, with attenuation upon CD36 knockdown. CONCLUSION: CD36 participates in macrophage and endothelial cell activation and MNGC formation, features of AAV pathogenesis. AAV treatment may involve targeting CD36 or MIF.

A case of rapid avacopan-induced liver injury in pediatric granulomatosis with polyangiitis.

Children with anti-neutrophil cytoplasmic antibody-associated vasculitis benefit immensely from avacopan as it reduces the requirement for steroids. However, descriptions of adverse drug reactions in children are lacking, and the dosage and follow-up intervals are unclear. A 10-year-old boy with initial granulomatosis and polyangiitis presented with diffuse pulmonary hemorrhage. Rituximab and 30 mg avacopan were administered twice daily as induction therapy following methylprednisolone pulse therapy. However, sudden liver function test abnormalities were observed on day 31 of avacopan treatment, despite liver enzyme levels being within the normal range 5 days earlier. A drug-induced lymphocyte stimulation and various infectious disease tests yielded negative results. Discontinuation of rituximab and avacopan resulted in improved liver function; no change in the Birmingham Vasculitis Activity Score during liver function test abnormalities was observed. Avacopan-associated abnormalities in liver function tests suggest that drug-induced liver injury may occur rapidly in children, and appropriate dosing strategies should be reconsidered.

Detailed tracking of antigen and antibody levels during coronavirus disease 2019 treatment in an immunosuppressed patient with anti-neutrophil cytoplasmic autoantibody-associated vasculitis.

A 67-year-old woman with anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis was not vaccinated against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and was on multiple immunosuppressive drugs. She was hospitalized because of interstitial shadowing in the lungs and diagnosed with persistent coronavirus disease 2019 (COVID-19). Despite treatment with a recombinant monoclonal antibody and antivirals, her symptoms persisted and she lacked a specific antibody response. She tested negative for SARS-CoV-2 antigen after the second antiviral treatment, and a subsequent chest radiograph showed improvement. However, the antibody levels did not change. This case highlights the importance of careful monitoring of the SARS-CoV-2 antigen and antibody levels during COVID-19 treatment in patients with immunosuppression.

Incidence of anti-neutrophil cytoplasmic antibody-associated renal vasculitis: a retrospective study in rural and regional Victoria, Australia.

BACKGROUND: The epidemiology of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) varies worldwide. Previous Australian studies described a higher incidence of AAV in rural areas; however, this has not yet been investigated in Victoria. AIMS: To calculate the incidence of AAV in rural and regional Victoria and characterise the demographics and clinical outcomes of this cohort. METHODS: We performed a retrospective review of patients with newly diagnosed AAV confirmed on renal biopsy at Bendigo Health between 2013 and 2021. Cases were classified according to the 2022 American College of Rheumatology/European Alliance of Associations for Rheumatology criteria. Local disease incidence was calculated using Estimated Resident Population data for our catchment, the Loddon Mallee region. RESULTS: Twenty-eight cases of new AAV were identified; 17 were classified as microscopic polyangiitis (MPA) and the remainder as granulomatosis with polyangiitis (GPA). The median age at diagnosis was 68 years (interquartile range (IQR): 59-77). The incidence per million person-years was 9.3 for AAV overall (95% CI: 6.2-13.5), 5.7 for MPA (95% CI: 3.3-9.1) and 3.7 for GPA (95% CI: 1.8-6.6). With a median follow-up time of 3.3 years (IQR: 1.9-5.6), one-quarter of patients relapsed (n = 7, 25%), and six required ongoing renal-replacement therapy (21%). CONCLUSIONS: The calculated incidence of AAV in rural and regional Victoria is not higher than the reported incidence in most urban Australian cohorts. This study may underestimate the true local disease incidence as only patients with renal vasculitis were included.

Variation in approaches to acute ANCA-associated vasculitis in Australia and New Zealand: rituximab, plasma exchange and glucocorticoids.

BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare autoimmune disease which is managed by a range of specialities. There are limited data on treatment practices in Australia and New Zealand. AIMS: To understand current patterns of acute AAV treatment in Australia and New Zealand. METHODS: An online survey was conducted between July and October 2022 investigating physicians' views on the management of AAV, focusing on induction therapy. The survey contained questions pertaining to access to treatment and responses to clinical management scenarios. Eosinophilic granulomatosis with polyangiitis was not included. A chi-squared test of independence was performed for statistical analysis. RESULTS: From a total of 55 responses, plasma exchange was difficult to access for 44% of respondents, more so in rural centres, and they also had difficulty accessing infusion centres. New Zealand clinicians had more difficulty accessing rituximab, with only 44% reporting easy access compared with Australian clinicians (93%). With clinical management scenarios, there was variation in the dosing regimen of glucocorticoids and initiation of plasma exchange, with 42% of respondents prescribing a glucocorticoid regimen different from the standard of care, the 'reduced-dose' arm of the Plasma Exchange and Glucocorticoids for the Treatment of ANCA-Associated Vasculitis trial. The choice of cyclophosphamide or rituximab for induction therapy was based on patient characteristics and medical history. CONCLUSIONS: There is substantial variation in approaches to the acute management of AAV in Australia and New Zealand, including differences in resource availability. This variation in care demonstrates the need to implement current practice guidelines and institute contemporary monitoring of AAV management, to achieve best patient outcomes.

Diagnostic delays in systemic vasculitides.

Systemic vasculitides are among the less common disorders encountered in routine rheumatology practice. The low incidence and heterogeneous presentation at onset can potentially lead to delayed diagnosis. Not recognizing these in the early phase may prove detrimental, as some vasculitis may progress to a catastrophic course with major morbidity or mortality. The causes of diagnostic delay may vary among different types of vasculitis and may also be disease-, patient-, or physician-related. Disease-related factors include the myriad presentations with diverse and non-specific symptoms, mimicking other conditions like infections. In addition, some forms have prolonged prodromal phases before evident organ damage. Limited awareness among healthcare professionals, particularly outside rheumatology, and a lack of readily available diagnostic tools contribute to missed diagnoses. Delays in seeking care due to non-specific symptoms or lack of access to specialist care can worsen outcomes. The economic burden also increases with delayed diagnosis and damage accrual when the disease remains unrecognized or untreated for prolonged periods. Although the causes of vasculitis are numerous, including secondary causes, in this review, we focus on diagnostic delays in primary vasculitides and suggest potential steps to identify and treat these diseases early. These include educating both healthcare professionals and the public about the signs and symptoms of vasculitis; expanding the rheumatology workforce and facilitating timely referrals; implementing readily available and reliable tests for early detection; and streamlining care and diagnostic pathways. Such measures have the potential to improve the overall outcomes of the disease, with prolonged remission, minimal damage accrual, and improved quality of life.

Use of mesna prophylaxis in patients with cyclophosphamide-treated ANCA-associated vasculitis: cross-sectional survey of practitioners.

BACKGROUND: There may be some diversity in the practice of co-prescribing 2-mercaptoethane sodium sulfonate (mesna) with cyclophosphamide (CYC) for ANCA-associated vasculitis (AAV). OBJECTIVES: To assess the practice of prescribing mesna prophylaxis for CYC-treated patients with AAV. METHODS: We invited authors of publications on AAV referenced in MEDLINE over the previous 10 years to participate in an anonymous online survey. Respondents were eligible if they were involved in CYC treatments for AAV. The survey asked about the characteristics of the respondents and their practice in using CYC and mesna to treat AAV and the underlying rationale. We compared 18 variables between mesna prescribers and their counterparts to identify factors associated with mesna use. RESULTS: In total, 139 eligible individuals completed the survey. The participants were from 34 countries and were essentially physicians (98%). Overall, 68%, 19% and 13% of respondents prescribed mesna systematically, never, or on a selective basis. As compared with never/selective-prescribers, systematic-prescribers were more often ≤ 39 years old (P = 0.008), more often used intermittent pulse therapy as the exclusive/predominant CYC administration scheme (P < 0.001), were more frequently based in France/Germany/Italy than in England/United States (P < 0.001), and more often indicated adherence to local standards (P = 0.003) or (inter)national guidelines for AAV (P < 0.001) as a rationale for their mesna practice. Never/selective-prescribers more commonly reported that their mesna prescription pattern had changed as compared with their former practice (P < 0.001). CONCLUSIONS: Systematic co-prescription of mesna is the prevailing practice for CYC treatments for AAV. The practice seems to involve practicability considerations and differs between generations.

Investigation of Clinical Features and Association between Vascular Endothelial Injury Markers and Cytomegalovirus Infection Associated with Thrombotic Microangiopathy in Patients with Anti-Neutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis: Case-Based Research.

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) can occasionally trigger thrombotic microangiopathy (TMA). Cytomegalovirus (CMV) may be reactivated during intensive immunosuppressive therapy for AAV and cause TMA. Therefore, we aimed to evaluate the clinical features of and the association between vascular endothelial injury markers and TMA due to CMV in patients with AAV. A 61-year-old female was diagnosed with AAV and severe kidney injury. Immunosuppressive therapy gradually improved her symptoms and laboratory findings. However, 2 weeks after induction therapy initiation, she exhibited altered consciousness, a significant decrease in platelet count, and hemolytic anemia, resulting in a TMA diagnosis. Plasma exchange did not improve TMA findings and routine screening test revealed CMV infection. Ganciclovir injection improved the infection and TMA findings. Consequently, we diagnosed her with CMV-induced TMA. Both AAV and CMV may induce severe vascular endothelial injury, potentially leading to TMA development. CMV-induced TMA should be considered when TMA develops during induction therapy against AAV. Moreover, of the three serum markers of vascular injury-serum sulfatides, soluble thrombomodulin, and pentraxin 3-serum sulfatides may be associated with the development of TMA, and a high level of soluble thrombomodulin may be associated with the development of CMV viremia during the clinical course of AAV.

[Clinical characteristics of children with anti-neutrophil cytoplasmic antibody-associated vasculitis]. / å„¿ç«¥æŠ—ä¸­æ€§ç²’ç»†èƒžèƒžè´¨æŠ—ä½“ç›¸å ³æ€§è¡€ç®¡ç‚Žä¸´åºŠç‰¹å¾åˆ†æž.

OBJECTIVES: To study the clinical characteristics of children with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: A retrospective analysis was conducted on the clinical data of 25 children diagnosed with AAV at the Second Xiangya Hospital of Central South University from January 2010 to June 2022. RESULTS: Among the AAV children, there were 5 males and 20 females, with a median age of onset of 11.0 years. Involvement of the urinary system was seen in 18 cases (72%); respiratory system involvement in 10 cases (40%); skin involvement in 6 cases (24%); eye, ear, and nose involvement in 5 cases (20%); joint involvement in 4 cases (16%); digestive system involvement in 2 cases (8%). Eleven cases underwent kidney biopsy, with 5 cases (46%) showing focal type, 2 cases (18%) showing crescentic type, 2 cases (18%) showing mixed type, and 2 cases (18%) showing sclerotic type. Immune complex deposits were present in 5 cases (45%). Seven cases reached chronic kidney disease (CKD) stage V, with 2 cases resulting in death. Two cases underwent kidney transplantation. At the end of the follow-up period, 2 cases were at CKD stage II, and 1 case was at CKD stage III. Of the 16 cases of microscopic polyangiitis (MPA) group, 13 (81%) involved the urinary system. Of the 9 cases of granulomatosis with polyangiitis (GPA), 6 cases (66%) had sinusitis. Serum creatinine and uric acid levels were higher in the MPA group than in the GPA group (P<0.05), while red blood cell count and glomerular filtration rate were lower in the MPA group (P<0.05). CONCLUSIONS: AAV is more common in school-age female children, with MPA being the most common clinical subtype. The onset of AAV in children is mainly characterized by renal involvement, followed by respiratory system involvement. The renal pathology often presents as focal type with possible immune complex deposits. Children with MPA often have renal involvement, while those with GPA commonly have sinusitis. The prognosis of children with AAV is poor, often accompanied by renal insufficiency.

Neutrophil extracellular trap formation in anti-neutrophil cytoplasmic antibody-associated and large-vessel vasculitis.

Levels of neutrophil extracellular traps (NETs) were measured in plasma of healthy controls (HC, n = 30) and patients with granulomatosis with polyangiitis (GPA, n = 123), microscopic polyangiitis (MPA, n = 61), Takayasu's arteritis (TAK, n = 58), and giant cell arteritis (GCA, n = 68), at times of remission or activity and correlated with levels of the platelet-derived thrombospondin-1 (TSP-1). Levels of NETs were elevated during active disease in patients with GPA (p < 0.0001), MPA (p = 0.0038), TAK (p < 0.0001), and GCA (p < 0.0001), and in remission for GPA, p < 0.0001, MPA, p = 0.005, TAK, p = 0.03, and GCA, p = 0.0009. All cohorts demonstrated impaired NET degradation. Patients with GPA (p = 0.0045) and MPA (p = 0.005) had anti-NET IgG antibodies. Patients with TAK had anti-histone antibodies (p < 0.01), correlating with presence of NETs. Levels of TSP-1 were increased in all patients with vasculitis, and associated with NET formation. NET formation is a common process in vasculitides. Targeting NET formation or degradation could be potential therapeutic approaches for vasculitides.

Prognostic value of proteinuria monitoring in anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVE: To determine the prognostic significance of proteinuria monitoring in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). METHODS: We retrospectively analyzed the data of kidney biopsy-confirmed patients with AAV. Proteinuria was evaluated by a urine dipstick test. Poor renal outcome was defined as stage 4/5 chronic kidney disease (CKD) (estimated glomerular filtration rate < 30 mL/min/1.73 m2). RESULTS: We enrolled 77 patients with a median follow-up duration of 36 months (interquartile range, 18-79) in this study. Excluding 8 patients on dialysis at 6 months, 59/69 (85.5%) achieved remission after induction therapy. Patients were then divided into two groups according to the presence of proteinuria at 6 months after induction therapy (n = 29 with proteinuria, 40 without proteinuria). There was no significant difference in the rate of relapse or death according to the presence of proteinuria (p = 0.304 relapse, 0.401 death). In contrast, patients with proteinuria had significantly lower kidney function than those without proteinuria (41 vs. 53.5 mL/min/1.73 m2, p = 0.003). Multivariate analysis revealed that eGFR values at 6 months (hazard ratio [HR] 0.925; 95% CI 0.875-0.978, p = 0.006) and proteinuria at 6 months (HR 4.613; 95% CI 1.230-17.298, p = 0.023) were significantly associated with stage 4/5 CKD. CONCLUSION: The presence of proteinuria at 6 months after induction therapy and low renal function was significantly associated with a higher risk of stage 4/5 CKD in patients with AAV. Monitoring for proteinuria after induction therapy may help predict poor renal outcomes in patients with AAV.

Kidney Histopathology Can Predict Kidney Function in ANCA-Associated Vasculitides with Acute Kidney Injury Treated with Plasma Exchanges.

BACKGROUND: Data from the PEXIVAS trial challenged the role of plasma exchange (PLEX) in ANCA-associated vasculitides (AAV). We aimed to describe kidney biopsy from patients with AAV treated with PLEX, evaluate whether histopathologic findings could predict kidney function, and identify which patients would most benefit from PLEX. METHODS: We performed a multicenter, retrospective study on 188 patients with AAV and AKI treated with PLEX and 237 not treated with PLEX. The primary outcome was mortality or KRT at 12 months (M12). RESULTS: No significant benefit of PLEX for the primary outcome was found. To identify patients benefitting from PLEX, we developed a model predicting the average treatment effect of PLEX for an individual depending on covariables. Using the prediction model, 223 patients had a better predicted outcome with PLEX than without PLEX, and 177 of them had >5% increased predicted probability with PLEX compared with without PLEX of being alive and free from KRT at M12, which defined the PLEX-recommended group. Risk difference for death or KRT at M12 was significantly lower with PLEX in the PLEX-recommended group (-15.9%; 95% CI, -29.4 to -2.5) compared with the PLEX not recommended group (-4.8%; 95% CI, 14.9 to 5.3). Microscopic polyangiitis, MPO-ANCA, higher serum creatinine, crescentic and sclerotic classes, and higher Brix score were more frequent in the PLEX-recommended group. An easy to use score identified patients who would benefit from PLEX. The average treatment effect of PLEX for those with recommended treatment corresponded to an absolute risk reduction for death or KRT at M12 of 24.6%. CONCLUSIONS: PLEX was not associated with a better primary outcome in the whole study population, but we identified a subset of patients who could benefit from PLEX. However, these findings must be validated before utilized in clinical decision making.

Serum Complement C4 Levels Are a Useful Biomarker for Predicting End-Stage Renal Disease in Microscopic Polyangiitis.

This study aimed to evaluate the risk factors for end-stage renal disease (ESRD) in microscopic polyangiitis (MPA). In total, 74 patients with MPA were enrolled, and we compared the baseline clinical characteristics and disease activity between MPA patients who have progressed to ESRD and those without ESRD to select predictive factors for ESRD. Out of 74 patients, 12 patients (16.2%) had ESRD during follow-up. Serum C4 levels were significantly higher in MPA patients who have progressed to ESRD than in those without ESRD (p = 0.009). Multivariate analyses revealed that high serum creatinine levels (odds ratio (OR) 4.4, 95% confidence interval (CI) 1.25-15.5) and high serum C4 levels (OR 1.24, 95% CI 1.03-1.49) were risk factors for ESRD. Using receiver operating characteristic analysis, the cut-off value for initial serum C4 levels and serum creatinine levels were 29.6 mg/dL and 3.54 mg/dL, respectively. Patients with MPA with a greater number of risk factors (serum C4 levels > 29.6 mg/dL and serum creatinine levels > 3.54 mg/dL) had a higher ESRD progression rate. Serum C4 levels were significantly positively correlated with serum creatinine levels and kidney Birmingham vasculitis activity score (p = 0.02 and 0.04, respectively). These results suggest that serum C4 levels are useful tools for assessing renal disease activity and prognosis in MPA.

Outcome of rituximab treatment in Japanese patients with ANCA-associated vasculitis in daily clinical practice: A two-centre study in Fukushima, Japan.

OBJECTIVES: Rituximab (RTX) efficacy for anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) has been reported in large randomized studies; however, the efficacy of RTX in Japanese AAV patients, especially the elderly, is not well known. We aimed to determine the clinical efficacy of RTX in Japanese AAV patients including elderly patients. METHODS: This study included 78 AAV patients newly diagnosed with AAV and treated in Fukushima Medical University Hospital or Ohta-Nishinouchi Hospital from April 2004 to September 2019. Clinical records were retrospectively reviewed, and clinical efficacy and outcome (1-year survival) between the RTX treatment group (23 cases) and the conventional therapy group (immunosuppressive therapy other than RTX, 55 cases) were compared. We also analysed the clinical efficacy and outcome in elderly-onset (>75 years) AAV patients. RESULTS: The RTX group showed similar efficacy and 1-year survival compared to the conventional therapy group. Conversely, after 6 months of treatment, prednisolone doses significantly decreased in the RTX group compared to the conventional therapy group (p < 0.01). In the elderly-onset AAV patients, clinical efficacy and outcome were not significantly different. CONCLUSIONS: RTX was effective in Japanese AAV patients and may be useful for prompt tapering of prednisolone doses, even in elderly-onset AAV patients.

Antiphospholipid antibody positivity and the thrombotic risk in Japanese patients with anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVES: It has been reported that 21.0-51.7% of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) patients were antiphospholipid antibody (aPL)-positive. However, the clinical significance of aPL positivity in AAV is not fully understood. METHODS: We retrospectively assessed patients with AAV diagnosed from 2013 to 2020 at our hospital. Positivity of aPL was defined as positivity of anti-cardiolipin antibody, anti-cardiolipin ß2 glycoprotein 1 complex antibody, and/or lupus anticoagulant at least one time during the follow-up periods. The thrombotic risk of aPL positivity was examined by multivariate analyses with the Cox regression model. RESULTS: A total of 93 patients with a median age of 71.9 years were included in the study. The median follow-up period was 35.4 months. Thirty-one patients (33.3%) were aPL-positive. Twenty-two thrombotic events occurred in 17 patients (18.3%). Thrombotic events occurred more frequently in aPL-positive patients than in aPL-negative patients (P = 0.011). Multivariate analyses with two different models identified aPL positivity as a thrombotic risk factor (hazard ratios 4.302 and 5.956, 95% confidence intervals 1.546-11.968 and 1.940-18.281, respectively). CONCLUSIONS: The proportion of aPL-positive patients was 33.3%, and aPL positivity increased the thrombotic risk in Japanese patients with AAV.

Clinical efficacy of protein A immunoadsorption therapy on severe ANCA-associated vasculitis renal injury. / 蛋白Aå ç–«å¸é™„æ²»ç–—é‡ç—‡ANCAç›¸å ³æ€§è¡€ç®¡ç‚Žè‚¾æŸä¼¤çš„ä¸´åºŠæ•ˆæžœ.

OBJECTIVES: The anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of diseases involving multiple systems, and kidney is one of the most commonly involved target organs. Some patients may rapidly progress to end-stage renal disease in a short time. Whereas some patients have poor remission and renal prognosis after standard induction therapy. As a selective blood purification therapy, protein a immunoadsorption (PAIA) has shown great advantages on treating of severe autoimmune diseases. This study aims to evaluate the short-term efficacy of PAIA therapy combined with glucocorticoids and immunosuppressants on treating of severe AAV renal injury. METHODS: A total of 10 AAV cases with severe kidney involvement in the Second Xiangya Hospital of Central South University from 2019 to 2020 were selected for this retrospective study. During the induction remission stage, each patient was treated with PAIA on the basis of standard therapy of glucocorticoids and immunosuppressive treatment. Before and after the initial treatment, 1 month and 3 months after treatment, clinical data including demographic characteristics, immunological indicators, and Birmingham Vasculitis Activity Score (BVAS) were compared. The related adverse reactions during treatment were recorded to evaluate the short-term efficacy. RESULTS: In this study, all 10 patients were MPO positive, and 2 patients were PR3 positive (≥2.3 U/mL). There are 6 males and 4 females at (61.5±11.4) years old, with the median time from onset to admission to hospital at (2.8±1.8) months. Multisystem damage, especially kidney damage, can be seen with eGFR lower than 30 mL/(min·1.73 m2). During the 3-month follow-up, BVAS, erythrocyte sedimentation rate, and hemoglobin of 10 patients showed continuous improvement compared with the initial admission levels (all P<0.05). ANCA titer, serum creatinine and urine red blood cell were all decreased and eGFR levels were increased in 3 months after treatment (all P<0.05). Serum albumin, urinary protein, C-reactive protein and complement levels showed no significant changes after treatment (all P>0.05). One patient who had received renal replacement therapy was still dialysis dependent after PAIA treatment. One patient who had transient hypotension was corrected by routine treatment. The rest of the patients were all tolerant with PAIA during their treatments. CONCLUSIONS: Treatment with PAIA combined with glucocorticoids and cyclophosphamide can rapidly lower serum ANCA level and improve disease activity in patients with AAV complicated with severe kidney damage, suggesting a good short-term renal prognosis and good overall safety.

Impaired repair properties of endothelial colony-forming cells in patients with granulomatosis with polyangiitis.

In patients with ANCA-associated vasculitis, interactions between neutrophils and endothelial cells cause endothelial damage and imbalance. Endothelial colony-forming cells (ECFCs) represent a cellular population of the endothelial lineage with proliferative capacity and vasoreparative properties. This study aimed to evaluate the angiogenic capacity of ECFCs of patients with granulomatosis with polyangiitis (GPA). The ECFCs of 13 patients with PR3-positive GPA and 14 healthy controls were isolated and characterized using fluorescence-activated cell sorting, capillary tube formation measurement, scratching assays and migration assays with and without plasma stimulation. Furthermore, three patients with active disease underwent post-treatment recollection of ECFCs for longitudinal evaluation. The ECFCs from the patients and controls showed similar capillary structure formation. However, the ECFCs from the patients with inactive GPA exhibited early losses of angiogenic capacity. Impairments in the migration capacities of the ECFCs were also observed in patients with GPA and controls (12th h, p = 0.05). Incubation of ECFCs from patients with GPA in remission with plasma from healthy controls significantly decreased migration capacity (p = 0.0001). Longitudinal analysis revealed that treatment significantly lowered ECFC migration rates. This study revealed that ECFCs from the patients with PR3-positive GPA in remission demonstrated early losses of tube formation and reduced migration capacity compared to those of the healthy controls, suggesting impairment of endothelial function.

ANCA-associated vasculitis with protein-losing enteropathy is characterized by hypocomplementemia.

Protein-losing enteropathy (PLE) has been reported to be associated with various systemic autoimmune diseases. However, reports regarding PLE in ANCA-associated vasculitis (AAV) patients are limited. We herein aimed to describe the clinical characteristics of AAV with PLE. We conducted a retrospective chart review of patients who were diagnosed with AAV and who began treatment at the University of Tokyo Hospital between June 2003 and June 2020. Among 68 AAV patients, there were four patients (5.9%) with PLE, consisting of two patients with MPA, one patient with GPA, and one patient with EGPA. Clinical courses were described, and their data were compared with AAV patients without PLE. Demographic characteristics, disease activity, and the pattern of organ involvement were similar between patients with PLE and without PLE. Patients with PLE had hypocomplementemia more frequently than the patients without PLE (CH50 75.0% vs 1.8%, p < 0.001, C3 50.0% vs 1.8%, p = 0.01, C4 75.0% vs 3.5%, p = 0.001). Although hypoalbuminemia improved with immunosuppressive therapy for AAV, the improvement in hypoalbuminemia was slow in most cases. We also performed a systematic review on PLE associated with vasculitis. Thirteen reports were included, and Henoch-Schonlein Purpura patients with PLE also tended to have hypocomplementemia. In conclusion, PLE is a rare complication of AAV and complement system may associate with the mechanism of PLE.

Anti-neutrophil cytoplasmic antibody associated vasculitis in patients with rheumatoid arthritis.

BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) may coexist with rheumatoid arthritis (RA). However, it is unclear whether the manifestations of AAV with and without coexisting RA are similar. This observational study aimed to investigate the clinicopathological manifestations of AAV with coexisting RA and to explore potential predictors for identifying AAV superimposed on RA. METHODS: Patients with both AAV and RA were identified by searching our hospital database and the literature. Data including age, sex, clinical manifestation, laboratory tests, renal pathology, and therapeutic regimens were retrieved. To assess the difference in clinical features and renal pathology between AAV patients with and without RA, we conducted 1:4 matched case-control studies. RESULTS: A total of 47 patients were identified, 15 from our hospital and 32 from the literature, and 33 (70.2%) were women. AAV was diagnosed later than RA in 83.0% of the patients and manifested as microscopic polyangiitis (MPA) in 78.7% of the patients. The kidney was the most frequently involved extra-articular organ (74.5%), followed by the lung (51.1%), and skin (8.5%). Patients with both AAV and RA were more likely to be asymptomatic (26.7% vs 3.3%, p = 0.013) than those with isolated AAV. However, they did not differ in other clinicopathological features. In RA patients, those with ANCA associated glomerulonephritis, were more likely to have decreased renal function at renal biopsy as opposed to those with primary glomerulonephritis. CONCLUSIONS: AAV can coexist with RA. In this coexistence, AAV usually develops after RA, is more likely to be asymptomatic, and manifests predominately as MPA with renal involvement. Thus, we should remain vigilant to superimposed AAV on RA.

Renal Amyloidosis Secondary to ANCA-Associated Vasculitis: A Case Report.

Renal amyloidosis secondary to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is extremely rare. Here, we reported a 77-year-old woman with ANCA-associated vasculitis. Renal biopsy with Masson trichrome staining showed pauci-immune crescentic glomerulonephritis, and electron microscopy showed amyloid deposition in the mesangial area. Immunofluorescence revealed kappa light chain and lambda light chain negative. Bone marrow biopsy revealed no clonal plasma cell. Finally, she was diagnosed as ANCA-associated vasculitis with secondary renal amyloid A amyloidosis.