Proteinase 3-ANCA Research Articles

Granulomatosis with polyangiitis with lacrimal gland enlargement and pancreatic swelling: case report and literature review.

A 62-year-old man had bilateral eyelid swelling for 4 months. Two months before admission, he developed fatigue and lost 5 kg of bodyweight. Further examination revealed elevated serum C-reactive protein, normal angiotensin-converting enzyme, elevated proteinase-3 antineutrophil cytoplasmic antibody (PR3-ANCA), and normal IgG4 concentration. Chest X-ray and computed tomography showed no enlarged hilar lymph nodes, but positron emission tomography-computed tomography showed fluorodeoxyglucose accumulation in both lacrimal glands, in lung nodules, and in the pancreas. Tissue biopsies of the lacrimal glands and pulmonary nodules showed granuloma with giant cells, but no IgG4-positive cells or fibrosis. Pancreatic tissue showed no findings of autoimmune pancreatitis. In the 2022 ACR/EULAR classification criteria for granulomatosis with polyangiitis, the total score was 10 points. Final comprehensive diagnosis was granulomatosis with polyangiitis, based on the negative results of differential diseases, such as IgG4-related diseases and sarcoidosis. Prednisolone 60 mg/day was started on day 8, and rituximab 500 mg/body/week on day 12. After beginning treatment, general malaise and lacrimal gland enlargement were resolved, PR3-ANCA and C-reactive protein became negative, and the nodular shadow in the lungs disappeared. This is the first report of granulomatosis with polyangiitis presenting both lacrimal gland and pancreatic lesions.

Study protocol for a randomised, phase II, double-blind, experimental medicine study of obinutuzumab versus rituximab in ANCA-associated vasculitis: ObiVas

IntroductionRelapses in ANCA-associated vasculitis (AAV) increase the incidence of end-organ damage and their prevention requires prolonged immunosuppressive therapy. Rituximab, a type I anti-CD20 B cell depleting monoclonal antibody, is the...

Sinonasal manifestations of granulomatosis with polyangiitis: A retrospective analysis

ObjectiveThis study aimed to examine the characteristics of nasal and imaging findings of sinonasal lesions in granulomatosis with polyangiitis (GPA) patients and how these lesions change over time in both the active and remission phases of the disease. MethodsWe retrospectively reviewed GPA patients with sinonasal lesions who were followed up at our department between January 2005 and December 2020. The following data were collected: age, sex, symptoms at initial presentation, anti-neutrophil cytoplasmic antibody (ANCA) type, and histopathological, nasal (initial and follow-up), and imaging (initial and follow-up) findings. ResultsThis study included 17 patients with GPA aged 30 to 79 years. Computed tomography (CT) of the sinuses showed mucosal thickening in 16 patients, bone thickening in 12, bone destruction in 4, and an orbital invasion mass in 3 at the time of diagnosis. After initiating treatment, mucosal thickening of the sinuses improved in 3 of 16 patients and remained unchanged in 13. Bone thickening at the time of diagnosis remained unchanged in 10 of 12 patients and worsened in 2; 1 patient displayed newly developed bone thickening. Destructive nasal findings on CT were positive for proteinase 3-ANCA. ConclusionsOur study revealed that mucosal thickening, bone thickening, bone destruction, and orbital invasion mass were major CT findings in patients with GPA. Intranasal findings such as granulations, crusting, and necrosis were seen in the active phase; moreover, saddle nose, loss of turbinate, and nasal septal perforation were subsequently seen in the course of the disease. Sinonasal findings of GPA vary depending on the disease stage and period.

Risk of Relapse of Antineutrophil Cytoplasmic Antibody-Associated Vasculitis in a Randomized Controlled Trial of Plasma Exchange and Glucocorticoids.

Relapses of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis are important events that can cause organ dysfunction and reduce quality of life. Understanding the effects of the initial treatments for ANCA-associated vasculitis on the subsequent risk of relapse may help guide monitoring and treatment. We performed a post hoc analysis of participants with severe ANCA-associated vasculitis enrolled in an international two-by-two factorial randomized controlled trial comparing the effects of plasma exchange (PLEX) to no PLEX and a regimen of reduced glucocorticoid exposure to a standard regimen. We estimated the effects of treatments on relapses of any severity using three competing risk time-to-event models adjusted for patient and disease characteristics and other treatments. Each model was adjusted for disease manifestations in different ways. Of 704 participants, 649 (92.2%) achieved remission and 147 (22.7%) experienced 204 relapses. The relapse rate was 10.3 (95% confidence interval [CI] 8.4-12.1) relapses per 100 patient-years. Neither the use of PLEX (subhazard ratio 0.91-0.94; 95% CIs range from 0.66 to 1.31) nor a glucocorticoid regimen (subhazard ratio 0.93-0.94; 95% CIs range from 0.67 to 1.35) appreciably changed the risk of relapse. Proteinase 3-ANCA and the presence of nonhemorrhagic respiratory manifestations of the disease at trial entry were associated with increased risks of relapse. Receiving dialysis at baseline and administration of oral cyclophosphamide as induction therapy were associated with lower risks of relapse. In patients with severe ANCA-associated vasculitis, relapses remain common; neither the use of PLEX nor an initial glucocorticoid tapering regimen impacted relapse risk.

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

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

Prevalence and characteristics of bronchiectasis in ANCA-associated vasculitis: A systematic review and meta-analysis

Objectives: This systematic review and meta-analysis aimed to investigate the prevalence of bronchiectasis (BR) in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), the association of BR with manifestations of AAV, and the features of BR in AAV. Materials and methods: PubMed, EMBASE, Web of Science, and Cochrane Library were searched for publications related to AAV and BR in English from January 1, 1994, until December 7, 2022. The prevalence of BR was synthesized using random-effects models, and sources of heterogeneity were assessed by sensitivity and subgroup analyses. Odds ratios (ORs) were calculated using fixed-effects models to evaluate the association of BR with manifestations of AAV. Only qualitative synthesis was performed on the features of BR. Results: Studies that reported on the prevalence (n=24), the association (n=6), and the features (n=8) of BR were identified. The pooled overall prevalence of BR among AAV was 19% (95% confidence interval [CI] 13-27%). The prevalence of patients with myeloperoxidase (MPO)-ANCA was significantly higher than those with proteinase 3-ANCA (28% vs. 13%, p=0.01). The female sex (OR=2.41), peripheral neuropathy (OR=4.58), MPO-ANCA (OR=4.73), and microscopic polyangiitis (OR=2.72) were associated with BR in AAV. Compared to individuals without BR, AAV-BR patients exhibited relatively lower levels of proteinuria. The diagnosis of BR could follow, be concomitant to, or precede that of AAV. However, BR usually did not respond to immunosuppressive therapy. Conclusion: AAV with BR is a common condition with special manifestations. The association of BR with AAV may not be accidental; however, the underlying pathogenesis remains to be clarified.

Clinical characteristics of hypertrophic cranial pachymeningitis in granulomatosis with polyangiitis: a retrospective single-center study in China.

Hypertrophic cranial pachymeningitis (HCP) is uncommon but a poorly understood complication of granulomatosis with polyangiitis (GPA). We conducted this retrospective study to elucidate the clinical characteristics and factors independently associated with granulomatosis with polyangiitis (GPA) complicated by hypertrophic cranial pachymeningitis (HCP) in China. We collected the medical records of 78 patients diagnosed with GPA who were admitted to the inpatient department of Peking Union Medical College Hospital between January 2003 and September 2021. Clinical features, laboratory and radiological findings, and Birmingham Vasculitis Activity Scores (excluding meningitis score) were recorded. A binary logistic regression analysis was performed to analyze factors independently associated with GPA-related HCP. Headache (100%) and cranial nerve palsy (61.5%) were common manifestations of HCP. Compared to 52 GPA patients without HCP, 26 patients with HCP required more time from initial symptoms to diagnosis, with a lower ratio of pulmonary and renal involvement, a higher ratio of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) positivity, conductive or sensorineural hearing loss, mastoiditis, and decreased vision or sudden visual loss. Binary logistic regression analysis indicated that proteinase 3-antineutrophil cytoplasmic antibody (PR3-ANCA) negativity (OR 10.698, p = 0.001), conductive or sensorineural hearing loss (OR 10.855, p = 0.005), and decreased vision or sudden visual loss (OR 8.647, p = 0.015) were significantly associated with GPA-related HCP. Of the 26 patients, 18 received methylprednisolone pulse treatment, and 18 received intrathecal injections of dexamethasone and methotrexate. HCP was a severe manifestation of GPA in our study. Independent factors associated with the occurrence of HCP in patients with GPA included PR3-ANCA negativity, conductive or sensorineural hearing loss, and decreased vision or sudden visual loss. Furthermore, GPA-related HCP was associated with higher disease activity, requiring more intensive treatments.

Antineutrophil Cytoplasmic Autoantibody-negative Pauci-immune Necrotizing Glomerulonephritis with Plasma Cell-rich Tubulointerstitial Nephritis Complicated with Pleuritis and Digital Ischemia.

Antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) predominantly affects small vessels. Almost all AAV patients are positive for myeloperoxidase- or proteinase 3-ANCA, and ANCA plays a crucial role in the pathogenesis of AAV. We herein report an ANCA-negative AAV patient with pauci-immune necrotizing glomerulonephritis and plasma cell-rich tubulointerstitial nephritis who was complicated with pleuritis and digital ischemia. ANCA-negative AAV is a rare clinical entity that is difficult to diagnose, and pleuritis and digital ischemia are rare manifestations of AAV. An early diagnosis and appropriate treatment are important, as any delay in the diagnosis may worsen the prognosis.

Impact of different ANCA serotypes on the long-term outcome of ANCA-associated vasculitis patients

Objectives To investigate the clinical features and long-term outcomes of Chinese anti-neutrophil cytoplasmic antibodies (ANCAs)-associated vasculitis (AAV) patients with different ANCA serotypes. Methods Two hundred and twenty-four AAV patients from January 2010 to June 2021 were divided into myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA groups. Clinical and long-term outcomes were compared. Results In this study, the average follow-up was 46.4 months (range 0.3–188.4 months). One hundred and seventy-seven (79.0%) patients were MPO–ANCA-positive and 47 were PR3–ANCA-positive; the mean age of MPO–ANCA positive patients at diagnosis was elder than that of PR3–ANCA positive patients (67.0 vs. 60.0 years, p = .004). Among PR3–ANCA-positive patients, ear, nose and throat symptoms were more common (p = .014). Between two ANCA serotypes, there were no differences in complement 3 (C3), Birmingham vasculitis activity score (BVAS), five-factor score (FFS) or other organ involvements. For all AAV patients, the overall survival rates at one, three and five years were 80.0%, 67.0% and 56.4%, respectively. The cumulative relapse-free rates of one, three and five years were 89.5%, 76.4% and 68.4%, respectively. The survival of AAV patients was unaffected by the ANCA serotype (p = .23). The ANCA serotype also had no effect on either disease relapse (p = .20) or remission rates (p = .10). In our study, PR3–ANCA patients showed a better long-term survival, as the 5-year survival rate and the 5-year relapse-free survival rate of PR3–ANCA patients were 60.7% and 76.9%, while that of MPO–ANCA patients were 55.2% and 65.8%, respectively. Rather than ANCA serotype, younger patients with milder kidney involvement and lower disease assessment scores (BVAS and FFS) might be more relevant to better prognosis. Conclusions The likelihood of induced remission, patient survival or disease recurrence is all unaffected by ANCA serotypes. A better prognosis is seen in younger patients with milder kidney involvement and lower BVAS/FFS scores.

Intestinal injury and vasculitis biomarkers in cats with feline enteric coronavirus and effusive feline infectious peritonitis.

To investigate intestinal injury, repair and vasculitis biomarkers that may illuminate the progression and/or pathogenesis of feline infectious peritonitis (FIP) or feline enteric coronavirus (FECV) infection. A total of 40 cats with effusive FIP (30 with abdominal effusion, AE group; 10 with thoracic effusion, TE group) and 10 asymptomatic but FECV positive cats (FECV group), all were confirmed by reverse transcription polymerase chain reaction either in faeces or effusion samples. Physical examinations and effusion tests were performed. Trefoil factor-3 (TFF-3), intestinal alkaline phosphatase (IAP), intestinal fatty acid binding protein (I-FABP), myeloperoxidase-anti-neutrophilic cytoplasmic antibody (MPO-ANCA) and proteinase 3-ANCA (PR3-ANCA) concentrations were measured both in serum and effusion samples. Rectal temperature and respiratory rate were highest in the TE group (p<0.000). Effusion white blood cell count was higher in the AE group than TE group (p<0.042). Serum TFF-3, IAP and I-FABP concentrations were higher in cats with effusive FIP than the cats with FECV (p<0.05). Compared with the AE group, TE group had lower effusion MPO-ANCA (p<0.036), higher IAP (p<0.050) and higher TFF-3 (p<0.016) concentrations. Markers of intestinal and epithelial surface injury were higher in cats with effusive FIP than those with FECV. Compared to cats with abdominal effusions, markers of apoptosis inhibition and immunostimulation to the injured epithelium were more potent in cats with thoracic effusion, suggesting the possibility of a poorer prognosis or more advanced disease in these patients.

The Association Between Age at Diagnosis and Disease Characteristics and Damage in Patients With ANCA-Associated Vasculitis.

This study examined the relationship between age at diagnosis and disease characteristics and damage in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Analysis of a prospective longitudinal cohort of patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic GPA (EGPA) in the Vasculitis Clinical Research Consortium (2013-2021). Disease cohorts were divided by age at diagnosis (years): children (<18), young adults (18-40), middle-aged adults (41-65), and older adults (>65). Data included demographics, ANCA type, clinical characteristics, Vasculitis Damage Index (VDI) scores, ANCA Vasculitis Index of Damage (AVID) scores, and novel disease-specific and non-disease-specific damage scores built from VDI and AVID items. Analysis included data from 1020 patients with GPA/MPA and 357 with EGPA. Female predominance in GPA/MPA decreased with age at diagnosis. AAV in childhood was more often GPA and proteinase 3-ANCA positive. Children with GPA/MPA experienced more subglottic stenosis and alveolar hemorrhage; children and young adults with EGPA experienced more alveolar hemorrhage, need for intubation, and gastrointestinal involvement. Older adults (GPA/MPA) had more neurologic manifestations. After adjusting for disease duration, medications, tobacco, and ANCA, all damage scores increased with age at diagnosis for GPA/MPA (P < 0.001) except the disease-specific damage score, which did not differ (P = 0.44). For EGPA, VDI scores increased with age at diagnosis (P < 0.009), whereas all other scores were not significantly different. Age at diagnosis is associated with clinical characteristics in AAV. Although VDI and AVID scores increase with age at diagnosis, this is driven by non-disease-specific damage items.

Role of bronchoscopy for respiratory involvement in granulomatosis with polyangiitis and microscopic polyangiitis.

This study describes data from bronchoscopy performed at the diagnosis of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). We conducted a retrospective study between 2004 and 2019 in patients aged >18 years with a diagnosis of microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA) who underwent bronchoscopy at onset of the disease. We collected bronchoalveolar lavage (BAL) and histological findings obtained during bronchoscopy. 274 patients with AAV were identified. Among 92 bronchoscopies, 62 were performed at diagnosis, and 58 procedures were finally analysed. Cough was more frequent in patients with MPA than GPA (p=0.02). The presence of endobronchial lesions (24.1%) was found to be significantly associated with GPA (p<0.0001) and proteinase 3-ANCA (p=0.01). The most frequent endobronchial lesions were inflammation and hyperaemia of the bronchial mucosa (50%), followed by stenoses (28%), ulcerations (21%) and mass-like granulomatosis (7%). The diagnostic yield of bronchial biopsies was useful for visible lesions (66.6% versus 0%; p=0.006). On BAL, diffuse alveolar haemorrhage (DAH) was detected in 31 (53.4%) patients and was more frequent in MPA patients (70.4% versus 38.7%; p=0.016). In 16.1% of DAH cases, BAL confirmed the diagnosis despite the absence of clinical or biological arguments. The incidence of microbial infections on BAL (38%) was similar between MPA and GPA (p=0.54). Bronchoscopy is an informative procedure at the onset of AAV disease in patients with respiratory manifestations. Endobronchial lesions are more frequently found in GPA and should be biopsied. BAL can be used to confirm DAH or diagnose superadded infection.

Development of a scoring system for predicting the severity of ulcerative colitis

Background and study aimsMonitoring disease activity in ulcerative colitis (UC) is critical in preventing long-term complications. This study aims to develop a scoring system using non-invasive indicators to predict endoscopic activities for ulcerative colitis (UC) patients. Patients and methodsAll enrolled patients with UC admitted to Shanghai Xinhua Hospital between June 2017 and January 2021 were enrolled, and their clinical data were retrospectively collected and a number of serological biomarkers concentrations were analyzed. Patients were categorized into mild and moderate-to-severe disease groups. Univariate and multivariate logistic regression was used to predict moderate-to-severe endoscopic activities, which were then incorporated into a nomogram to establish a prediction scoring model. ResultOverall, 231 patients were divided into a mild group (n = 111, 48.0%) and a moderate-to-severe group (n = 120, 52.0%). The following variables were independently associated with the disease severity and were subsequently included into the prediction model: Proteinase 3 antineutrophil cytoplasmic antibody (PR3-ANCA), C-reactive protein (CRP), hemoglobin(Hb), IL-10, stool frequency ≥ 5 times/day and hematochezia. Incorporating these 6 factors, the nomogram showed good discrimination with C-index of 0.819 and reliable calibration. A scoring model was established with the area under the curve 0.818. Moreover, PR3-ANCA and CRP correlated with the duration of hospital stay. ConclusionWe developed a predictive model for endoscopic disease activities by using noninvasive factors based on PR3-ANCA, CRP, Hb, IL-10, stool frequency and hematochezia. This prediction model might assist clinicians in managing patients with UC.

Comparative Effectiveness of Rituximab- Versus Cyclophosphamide-Based Remission Induction Strategies in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis for the Risk of Kidney Failure and Mortality.

To compare rituximab- versus cyclophosphamide-based remission induction strategies for the long-term risks of kidney failure and death in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in a real-world cohort. We performed a cohort study using the Mass General Brigham AAV Cohort, which includes proteinase 3-ANCA+ and myeloperoxidase (MPO)-ANCA+ AAV patients diagnosed from January 1, 2002 to December 31, 2019. We included cases in which the initial remission induction strategy was based either on rituximab or cyclophosphamide. The primary outcome was the composite outcome of kidney failure or death. We used multivariable Cox proportional hazards models and propensity score-matched analyses to assess the association of rituximab- versus cyclophosphamide-based treatment strategies with the composite outcome of kidney failure or death. Of 595 included patients, 352 patients (~60%) received rituximab-based and 243 patients (~40%) received cyclophosphamide-based regimens. The mean age was 61 years, 58% of patients were female, 70% of patients were MPO-ANCA+, and 69% of patients had renal involvement (median estimated glomerular filtration rate 37.3 ml/minute/1.73 m2 ). There were 133 events at 5 years, and the incidence rates in rituximab- and cyclophosphamide-based regimens were 6.8 and 6.1 per 100 person-years, respectively. The risk of kidney failure or death was similar in both groups in multivariable-adjusted analyses (hazard ratio [HR] 1.03 [95% confidence interval (95% CI) 0.55-1.93]) and in propensity score-matched analyses (HR 1.05 [95% CI 0.55-1.99]) at 5 years. Our findings were similar when outcomes were assessed at 1 and 2 years as well as in subgroups stratified according to renal involvement and severity as well as major organ involvement. Rituximab- and cyclophosphamide-based remission induction strategies for AAV are associated with similar risks of kidney failure and death.

Association Between HLA-DPB1 and Antineutrophil Cytoplasmic Antibody-Associated Vasculitis in Children.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare, life-threatening inflammation of blood vessels that can affect both adults and children. Compared to adult-onset disease, AAV is especially rare in children, with an annual prevalence of 0.5-6.4 cases per million children. The etiology of AAV remains largely unknown, and both environmental and genetic factors are likely involved. The present study was undertaken to explore the genetic susceptibility factors recently identified in adult patients, including HLA-DP and HLA-DQ, in pediatric patients. We performed a genome-wide association study of pediatric AAV in patients of European ancestry (n=63 AAV cases, n=315 population-matched controls). We identified a significant genetic association between pediatric AAV and the HLA-DPB1*04:01 allele (P=1.5 × 10-8 , odds ratio [OR] 3.5), with a stronger association observed in children with proteinase 3-ANCA positivity than in children with myeloperoxidase-ANCA positivity. Among the HLA alleles, the HLA-DPB1*04:01 allele was the most highly associated with AAV, although not significantly, in a follow-up adult AAV cohort (P=2.6 × 10-4 , OR 0.4). T cell receptor and interferon signaling pathways were also shown to be enriched in the pediatric AAV cohort. The HLA-DPB1 locus showed an association with pediatric AAV, as similarly shown previously in adult AAV. Despite the difference in the age of onset, these findings suggest that childhood- and adult-onset vasculitis share a common genetic predisposition. The identification of genetic variants contributing to AAV is an important step to improved classification tools and treatment strategies.

Association of HLA-class II alleles with risk of relapse in myeloperoxidase-antineutrophil cytoplasmic antibody positive vasculitis in the Japanese population.

Disease relapse remains a major problem in the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). In European populations, HLA-DPB1*04:01 is associated with both susceptibility and relapse risk in proteinase 3-ANCA positive AAV. In a Japanese population, we previously reported an association between HLA-DRB1*09:01 and DQB1*03:03 with susceptibility to, and DRB1*13:02 with protection from, myeloperoxidase-ANCA positive AAV (MPO-AAV). Subsequently, the association of DQA1*03:02, which is in strong linkage disequilibrium with DRB1*09:01 and DQB1*03:03, with MPO-AAV susceptibility was reported in a Chinese population. However, an association between these alleles and risk of relapse has not yet been reported. Here, we examined whether HLA-class II is associated with the risk of relapse in MPO-AAV. First, the association of HLA-DQA1*03:02 with susceptibility to MPO-AAV and microscopic polyangiitis (MPA) and its relationship with previously reported DRB1*09:01 and DQB1*03:03 were examined in 440 Japanese patients and 779 healthy controls. Next, the association with risk of relapse was analyzed in 199 MPO-ANCA positive, PR3-ANCA negative patients enrolled in previously reported cohort studies on remission induction therapy. Uncorrected P values (Puncorr) were corrected for multiple comparisons in each analysis using the false discovery rate method. The association of DQA1*03:02 with susceptibility to MPO-AAV and MPA was confirmed in a Japanese population (MPO-AAV: Puncorr=5.8x10-7, odds ratio [OR] 1.74, 95% confidence interval [CI] 1.40-2.16, MPA: Puncorr=1.1x10-5, OR 1.71, 95%CI 1.34-2.17). DQA1*03:02 was in strong linkage disequilibrium with DRB1*09:01 and DQB1*03:03, and the causal allele could not be determined using conditional logistic regression analysis. Relapse-free survival was shorter with nominal significance in carriers of DRB1*09:01 (Puncorr=0.049, Q=0.42, hazard ratio [HR]:1.87), DQA1*03:02 (Puncorr=0.020, Q=0.22, HR:2.11) and DQB1*03:03 (Puncorr=0.043, Q=0.48, HR:1.91) than in non-carriers in the log-rank test. Conversely, serine carriers at position 13 of HLA-DRβ1 (HLA-DRβ1_13S), including DRB1*13:02 carriers, showed longer relapse-free survival with nominal significance (Puncorr=0.010, Q=0.42, HR:0.31). By combining DQA1*03:02 and HLA-DRβ1_13S, a significant difference was detected between groups with the highest and lowest risk for relapse (Puncorr=0.0055, Q=0.033, HR:4.02). HLA-class II is associated not only with susceptibility to MPO-AAV but also with risk of relapse in the Japanese population.

PRTN3 variant correlates with increased autoantigen levels and relapse risk in PR3-ANCA versus MPO-ANCA disease.

A GWAS of patients with anti-neutrophil cytoplasmic antibodies (ANCAs) found an association between proteinase-3 ANCA (PR3-ANCA) and a single nucleotide polymorphism (rs62132293) upstream of PRTN3, encoding PR3. The variant (G allele) was shown to be an expression quantitative trait locus in healthy controls, but the clinical impact remains unknown. Longitudinally followed patients with ANCA and healthy controls were genotyped. Gene expression was quantified by real-time quantitative PCR from leukocyte RNA. Plasma PR3 was quantified by ELISA. Among patients, variant carriers had elevated leukocyte PRTN3 expression compared with noncarriers (C/G vs. C/C and G/G vs. C/C). Healthy controls had low PRTN3 regardless of genotype. Myeloperoxidase (MPO) expression did not differ by genotype. PRTN3 expression correlated with circulating PR3, and variant carriers had higher plasma PR3 compared with noncarriers. Among variant carriers, there was an increased risk of relapse in patients with PR3-ANCA versus MPO-ANCA. The risk allele marked by rs62132293 is clinically significant as it is associated with increased autoantigen and may, in part, explain increased relapse in PR3-ANCA. Our results underscore the role of autoantigen availability in ANCA vasculitis.

Vasculitis Activity-Predicting Ability of IL-12 Family Cytokines in Patients with Microscopic Polyangiitis and Granulomatosis with Polyangiitis.

The present study investigated and compared the antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) activity-predicting ability of the serum concentrations of the four interleukin (IL)-12 family cytokines including IL-23, IL-27, IL-35, and IL-39 in patients with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA). The present study included 70 patients with MPA and GPA. Clinical and laboratory data, particularly Birmingham Vasculitis Activity Score (BVAS), at the time of blood collection were obtained. The serum concentrations of IL-23, IL-27, IL-35, and IL-37 were measured using sera stored at -80℃. Patients were divided into two groups: the upper half of BVAS (BVAS ≥12) and the lower half of BVAS (BVAS <12). The serum concentrations of IL-23 and IL-27 reflected AAV activity. Patients with the upper half of BVAS exhibited significantly higher serum concentrations of IL-23 and IL-27 than those without. Patients with the serum concentrations of IL-23 ≥132.1 pg/mL or IL-27 ≥684.7 pg/mL exhibited higher frequency and risk for the upper half of BVAS than those without [relative risks (RR) 5.143 and RR 4.091, respectively]. The serum concentrations of IL-27 were associated with age ≥65 years and proteinase 3-ANCA (or C-ANCA) negativity, whereas, those of IL-23 were associated with MPA. However, the serum concentrations of IL-35 and IL-39 were not useful in predicting AAV activity in this study. The present study is the first to demonstrate that among the various members of IL-12 family cytokines, the serum concentrations of IL-23 and IL-27 possess AAV activity-predicting ability.

Skin Ulcer Localized to the Scalp Due to Granulomatous Vasculitis with Positive Proteinase 3-antineutrophil Cytoplasmic Antibody

88 歳，男性。2 型糖尿病，高血圧症，脂質異常症，高尿酸血症などがある。当科初診の半月前に，頭皮全体に強い痛みを伴う皮疹を自覚し，近医皮膚科を受診した。皮疹部から皮膚生検を行うも，診断には至らなかった。痛みと共に病変の壊死が著明となり進行するため当科を紹介され受診した。当科初診時，前頭部から頭頂部を中心に，頭皮全体にわたり強い疼痛を伴う暗紅色斑から紫斑，壊死へと進行する皮疹を認めた。頭皮以外には皮疹はみられなかった。発熱および明らかな全身症状はなかった。血液検査では proteinase 3（PR3）-ANCA が 14.2 U/ml と軽度高値であった。病変部からの皮膚生検病理検査で肉芽腫性血管炎の所見を認めた。多発血管炎性肉芽腫症 granulomatosis with polyangiitis（GPA）を疑い，画像検査，他科コンサルトを行ったが，頭皮以外に特記すべき異常所見は認めなかった。プレドニゾロン 20 mg/日内服を主とした治療を開始したところ，皮疹および疼痛は比較的速やかに改善した。自験例は頭皮に生じた皮膚限局性 GPA ではないかと考えた。皮膚限局性 GPA は比較的稀な病態と思われるため，報告する。

IgA vasculitis with transient glomerular hematuria, diarrhea, and pericarditis following COVID-19 mRNA vaccination in a young patient with possible pre-existing ulcerative colitis.

Exacerbations or de novo autoimmune/autoinflammatory disease have been reported after COVID-19 vaccination. A young male presented with cutaneous IgA vasculitis with glomerular hematuria, diarrhea and pericarditis following his second COVID-19 mRNA vaccination. He also showed positivity for proteinase 3 anti-neutrophil cytoplasmic antibody (PR3-ANCA) and anti-cardiolipin antibody. Skin biopsy was compatible to IgA vasculitis. His purpura subsided and hematuria spontaneously disappeared. Treatment with anti-inflammatory medications and prednisolone resolved the pericarditis. He had a history of persistent diarrhea, and colonic biopsies showed possible ulcerative colitis without vasculitis. Kidney biopsy after prednisolone therapy revealed minor glomerular abnormalities without any immune reactants and did not show vasculitis. After prednisolone treatment, PR3-ANCA decreased in a medium degree despite of improvement of symptoms and inflammatory data, suggesting that his PR3-ANCA may be associated with ulcerative colitis. The cause of the transient glomerular hematuria was unclear, however, it might be caused by focal glomerular active lesions (glomerular vasculitis) due to vaccine-induced IgA vasculitis with nephritis. This case highlights that COVID-19 mRNA vaccination can activate multiple autoimmune/autoinflammatory systems. The conditions might help us better understand the mutual mechanisms of the relevant disorders.