2022 American College of Rheumatology/European Alliance of Associations for Rheumatology classification criteria for granulomatosis with polyangiitis

IL-6 Receptor Expression on the Surface of T Cells and Serum Soluble IL-6 Receptor Levels in Patients with Microscopic Polyangiitis and Granulomatosis with Polyangiitis

We investigated the IL-6 receptor (IL-6R) expression on the surface of T cells isolated from peripheral blood mononuclear cells (PBMCs) of microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) patients and measured the serum soluble IL-6R (sIL-6R) levels in these patients. Sera and PBMCs were obtained from 51 patients with MPA (n = 32) and GPA (n = 19), with 25 patients having active disease (defined as a Birmingham Vasculitis Activity Score [BVAS] ≥ 5). The median age of patients was 67.0 years, and 52.9% were women. Serum IL-6 levels were significantly correlated with the BVAS (r = 0.384); however, IL-6R expression on the surface of T cells did not significantly differ based on disease activity. Meanwhile, IL-6R expression on the surface of stimulated CD4+ (median mean fluorescence intensity [MFI] 588.0 vs. 1314.8; p < 0.001), CD4+CD25+ (MFI 853.3 vs. 1527.3; p < 0.001), and CD4+CD45RO+ (MFI 679.5 vs. 1241.5; p < 0.001) T cells was significantly reduced compared with unstimulated conditions. Conversely, patients with active disease exhibited a significantly higher median serum sIL-6R level than those with inactive disease (38.1 ng/mL vs. 34.7 ng/mL; p = 0.029). These results imply that the trans-signalling IL-6 pathway may be more activated than the classical signalling pathway in patients with MPA and GPA, suggesting the therapeutic potential of targeting sIL-6R.

Induction failure in granulomatosis with polyangiitis: a nationwide case-control study of risk factors and outcomes

OBJECTIVE

To identify characteristics of granulomatosis with polyangiitis (GPA) associated with induction failure, describe salvage therapies and their efficacy.

METHODS

We conducted a nationwide retrospective case-control study of GPA with induction failure between 2006 and 2021. Each patient with induction failure was randomly paired to three controls matched for age, sex and induction treatment.

RESULTS

We included 51 patients with GPA and induction failure (29 men and 22 women). At induction therapy, median age was 49 years. Twenty-seven patients received intravenous cyclophosphamide (ivCYC) and 24 rituximab (RTX) as induction therapy. Patients with ivCYC induction failure more frequently had PR3-ANCA (93% vs 70%, P = 0.02), relapsing disease (41% vs 7%, P < 0.001) and orbital mass (15% vs 0%, P < 0.01) compared with controls. Patients with disease progression despite RTX induction therapy more frequently had renal involvement (67% vs 25%, P = 0.02) with renal failure (serum creatinine >100 µmol/l in 42% vs 8%, P = 0.02) compared with controls. After salvage therapy, remission was achieved at 6 months in 35 (69%) patients. The most frequent salvage therapy was switching from ivCYC to RTX (or vice versa), showing an efficacy in 21/29 (72%). Remission was achieved in nine (50%) patients with inappropriate response to ivCYC, while in patients with progression after RTX induction, remission was achieved in four (100%) who received ivCYC (with or without immunomodulatory therapy), but only in three (50%) after adding immunomodulatory therapy alone.

CONCLUSION

In patients with induction failure, characteristics of GPA, salvage therapies and their efficacy vary according to induction therapy and failure modality.

Immune-Mediated Hypertrophic Pachymeningitis and its Mimickers: Magnetic Resonance Imaging Findings

Hypertrophic pachymeningitis (HP) is a rare and chronic inflammatory disorder presenting as localized or diffuse thickening of the dura mater. It can be idiopathic or an unusual manifestation of immune-mediated, infectious, and neoplastic conditions. Although some cases may remain asymptomatic, HP can lead to progressive headaches, cranial nerve palsies, hydrocephalus, and other neurological complications, which makes its recognition a fundamental step for prompt treatment. Regarding the diagnosis workup, enhanced MRI is the most useful imaging method to evaluate dural thickening. This article addresses the MR imaging patterns of immune-mediated HP, including immunoglobulin G4-related disease, neurosarcoidosis, granulomatosis with polyangiitis, rheumatoid pachymeningitis, and idiopathic HP. The main infectious and neoplastic mimicking entities are also discussed with reference to conventional and advanced MR sequences.

Fever of Unknown Origin in a Patient With Human Immunodeficiency Virus

Fever of unknown origin (FUO) presents a diagnostic challenge, particularly in patients with human immunodeficiency virus (HIV) due to their immunocompromised state. We report a case of a 21-year-old male with HIV who presented with persistent fever and was found to have a positive proteinase-3 antibody, raising suspicion of granulomatosis with polyangiitis (GPA). The patient's symptoms, negative infectious workup, and elevated proteinase-3 levels prompted consideration of non-infectious etiologies. Despite the absence of renal involvement, corticosteroid therapy was initiated, leading to the resolution of fever. However, the false positive association of proteinase-3 in HIV patients introduces uncertainty regarding the definitive diagnosis of GPA. A tissue biopsy would have provided further clarity, but it was not performed in this case. Our workup aligns more closely with a diagnosis of GPA, considering the patient's response to treatment and the absence of clinical deterioration. This case highlights the complexity of diagnosing non-infectious causes of FUO in HIV-infected individuals. It emphasizes the need for a multidisciplinary approach involving infectious disease specialists and rheumatologists to ensure accurate diagnosis and appropriate management.

Overlap Syndrome Consisting of Polymyositis/Dermatomyositis and ANCA-Associated Vasculitis According to the 2022 ACR/EULAR Criteria for Vasculitis: A Korean Single-Centre Study

The present study applied the 2022 American College of Rheumatology and European Alliance of Associations for Rheumatology classification criteria (the 2022 ACR/EULAR criteria) for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) to ANCA-positive patients with polymyositis (PM)/dermatomyositis (DM). Also, this study investigated how many patients could be diagnosed with overlap syndrome consisting of PM/DM and AAV. Twelve ANCA-positive patients with PM/DM were included and analysed in this study. The 2022 ACR/EULAR classification criteria for microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic GPA (EGPA) are scoring systems, and when a total score is over five in cases of MPA and GPA and over six in cases of EGPA, AAV can be classified. The median age of 12 ANCA-positive patients (six with PM and six with DM) was 54.0 years and one patient (8.3%) was male. Of the 12 ANCA-positive patients with PM/DM, 11 had myeloperoxidase (MPO)-ANCA (or perinuclear [P]-ANCA) and the remaining one had proteinase 3 (PR3)-ANCA (or cytoplasmic [C]-ANCA). Nine (75.5%) and one (8.3%) ANCA-positive patients with PM/DM were diagnosed with overlap syndrome consisting of PM/DM and MPA and overlap syndrome consisting of PM/DM and GPA, respectively. The main contributors to the classification of MPA and GPA were interstitial lung disease and renal vasculitis, along with ANCA positivity, respectively. In conclusion, this study was the first to demonstrate that 83.3% of them could be diagnosed with overlap syndrome consisting of PM/DM and AAV according to the 2022 ACR/EULAR criteria for AAV.

Changes in Lipids in Granulomatosis with Polyangiitis Relates to Glucocorticoids and History of Hypertension

Granulomatosis with polyangiitis (GPA) is an ANCA-associated small-vessel vasculitis. Vessel wall inflammation induces multiple vascular damages, leading to accelerated atherosclerosis. Metabolic profile and cardiovascular risk are somewhat understood in GPA patients. Cardiovascular atherosclerotic disease (ASCVD) may represent a risk for outcomes. Our purpose is to evaluate ASCVD risk in GPA patients. Thirty-six patients received GPA diagnosis (T0) and were evaluated after 1 (T1) and 2 (T2) years follow-up. All patients were treated with high-dose glucocorticoid, one-year tapered, along with immunosuppressants. Total cholesterol significantly increased in T1 vs. T0 and T2. LDL exhibited the same trend, while triglycerides increased in both T1 and T2 vs. T0. No difference was found in HDL. A significant hsCRP decrease was detected at T1 and T2 vs. T0, but not between T2 and T1. Moreover, we found a significant reduction in ESR at T2 compared with T1 and T0 and at T1 compared to T0. Hypertensive patients presented a pronounced increase in lipids, while inflammation reduced slowly compared to normotensives. Our data suggest that the increase in cholesterol and LDL in T1 is a consequence of glucocorticoids. These data can be useful in the evaluation of both CV diseases and lipid metabolism, which are closely related to vessel inflammation.

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

PURPOSE

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).

MATERIALS AND METHODS

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).

RESULTS

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.

CONCLUSION

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.

Soluble triggering receptor expressed on myeloid cell-1 reflects the cross-sectional activity of microscopic polyangiitis and granulomatosis with polyangiitis

Objectives

We investigated whether soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) reflects cross-sectional activity of microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA).

Methods

Forty-seven MPA and 32 GPA patients with well-documented clinical records and stored sera were enrolled. sTREM-1 levels were evaluated using Magnetic Luminex® assay, and disease activity was assessed using Birmingham vasculitis activity score (BVAS). Patients were divided into two groups according to the upper and lower halves of BVAS. Receiver operator characteristic (ROC) curve analysis was used to identify cut-off for determining upper half of BVAS. Linear and binary logistic regression was performed to evaluate the association between sTREM-1 and disease activity and status.

Results

The median age of patients was 67.0 years, and 58.2 % were women. The median BVAS and sTREM-1 were 12.0 and 467.1 pg/mL. sTREM-1 was significantly correlated with BVAS along with five-factor score, Short-Form 36-Item Health Surveys, and C-reactive protein. In multivariable linear regression analysis, erythrocyte sedimentation rate (standardised β 0.241), and sTREM-1 (standardised β 0.288) were correlated with BVAS. ROC analysis revealed that the cut-off of sTREM-1 for the upper half of BVAS was 474.1 pg/mL. MPA and GPA patients with sTREM-1 ≥474.1 pg/mL exhibited a significantly higher risk for the upper half of BVAS than those without (relative risk 5.932). Multivariable logistic regression analysis demonstrated sTREM-1 ≥474.1 pg/mL (odds ratio 5.662) was associated with the upper half of BVAS.

Conclusion

sTREM-1 reflects the activity of MPA and GPA, suggesting its role as a potential biomarker for assessing disease severity.

Not Everything Is as It Seems: A Case Series and Overview of Diseases Mimicking Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare heterogeneous disease in which treatment must be initiated early to prevent irreversible organ damage and death. There are several diseases that can mimic AAV, even in the presence of positive ANCA serology and/or histological evidence of vasculitis, as demonstrated in this case series. We reflect on the diagnostic approach of patients with AAV and provide an overview of AAV-mimicking diseases that can be considered in patients with atypical disease presentation or course.

Eosinophilic Granulomatosis with Polyangiitis: Latest Findings and Updated Treatment Recommendations

Eosinophilic granulomatosis with polyangiitis (EGPA) causes necrotizing vasculitis and eosinophil-rich granulomatous inflammation in small- to medium-sized vessels, resulting in multiple organ damage. EGPA is classified as an antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, with myeloperoxidase-ANCA detected in approximately one-third of the patients. Conventional treatment of EGPA relies on systemic glucocorticoids (GCs) in combination with cyclophosphamide when poor prognostic factors are present; however, the dilemma between disease control and drug-related adverse effects has long been a challenge. Recent studies have revealed that the genetic background, pathophysiology, and clinical manifestations differ between ANCA-positive and ANCA-negative patients; however, mepolizumab, an interleukin (IL)-5 inhibitor, is effective in both groups, suggesting that the IL-5-eosinophil axis is deeply involved in the pathogenesis of both ANCA-positive and ANCA-negative EGPA. This review summarizes the latest knowledge on the pathophysiology of EGPA and focuses on the roles of eosinophils and ANCA. We then introduce the current treatment recommendations and accumulated evidence for mepolizumab on EGPA. Based on current unmet clinical needs, we discuss potential future therapeutic strategies for EGPA.

Unilateral diaphragmatic palsy and pleuropericarditis in a patient with granulomatosis with polyangiitis: a case report

BACKGROUND

Granulomatosis with polyangiitis (GPA) is a rare small vessel vasculitis predominantly affecting upper and lower respiratory tract and kidneys. Unilateral diaphragmatic palsy could be a rare manifestation of GPA. Here we report a case of GPA in a 45-year-old male with unilateral diaphragmatic palsy with pleuropericarditis.

CASE PRESENTATION

We report a case of a 45-year-old Khas male who presented with acute onset chest pain and shortness of breath who had elevated right hemidiaphragm, bilateral pleural effusion and pericardial effusion who was later diagnosed as GPA.

CONCLUSIONS

GPA should be suspected in all patients with diaphragmatic palsy and pleuropericarditis with appropriate clinical and laboratory picture.

Vasculitis: When to Consider this Diagnosis?

Vasculitis is a diverse group of disorders involving inflammation of the blood vessels. Approaching the diagnosis of vasculitis can be challenging, given the differing clinical presentation and organ manifestations. Often vasculitis is a diagnosis that is considered too late, given the heterogeneous presentation and various mimics. This article aims to provide physicians with a diagnostic approach to vasculitis.

Systematic review and meta-analysis for 2023 clinical practice guidelines of the Japan Research Committee of the Ministry of Health, Labour, and Welfare for Intractable Vasculitis for the management of ANCA-associated vasculitis

OBJECTIVES

The objective of this study is to provide evidence for the revision of clinical practice guidelines for the management of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis by the Japan Research Committee for Intractable Vasculitis.

METHODS

PubMed, CENTRAL, and the Japan Medical Abstracts Society databases were searched for articles published between 2015 and 2020 to update the systematic review for existing clinical questions, while PubMed, CENTRAL, EMBASE, and the Japan Medical Abstracts Society were searched for articles published between 2000 and 2020 to conduct a systematic review for newly developed clinical questions. The certainty of evidence was assessed with the GRADE approach.

RESULTS

For remission induction, when used in conjunction with cyclophosphamide or rituximab, reduced-dose glucocorticoid lowered the risk of serious adverse events compared to standard-dose glucocorticoid. Avacopan improved sustained remission at 12 months compared to high-dose glucocorticoid. Addition of plasma exchange to remission induction therapy did not reduce the risk of death, end-stage kidney disease, or relapse. For remission maintenance, rituximab reduced the risk of relapse compared to azathioprine. Long-term rituximab or azathioprine reduced the risk of relapse compared to short-term rituximab or azathioprine, respectively.

CONCLUSIONS

This systematic review provided evidence required to develop the 2023 clinical practice guideline for the management of ANCA-associated vasculitis.

[Complement in vasculitis associated with anti-neutrophil cytoplasm antibodies with renal involvement: pathogenic, prognostic and therapeutic implications]

Antineutrophil cytoplasmic antibody-associated vasculitides are primary vasculitides that affect small vessels in various organs, including the kidney. Renal involvement is characterized by the presence of glomerulonephritis with crescents and necrosis in light microscopy and a pauci-immune pattern in immunofluorescence. The participation of complement in the pathogenesis of these entities has been valued in recent years, initially in animal models and later in studies in humans, by demonstrating the presence of fragments of the alternative complement pathway, in plasma and urine, together with complement deposits in glomeruli and small vessels of patients affected by antineutrophil cytoplasmic antibody vasculitis. The presence of complement in these entities confers a worse general and renal prognosis.

Vasculitis and Pregnancy: Disease State and Management

Family planning in women with vasculitis requires an interdisciplinary approach. This article summarizes recommendations and guidance for each phase of family planning in persons with vasculitis including preconception counseling, birth control, pregnancy, and breastfeeding. Pregnancy complications are presented by category of vasculitis with accompanying diagnostic and therapeutic recommendations. Birth control and assisted reproductive technology options are reviewed with special considerations for women who are high risk or have a history of blood clots. This article can be used as a clinical reference for reproductive discussions in all patients with vasculitis.

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

Background

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

Methods

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

Results

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

Conclusion

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

Case report: A pediatric case of MPO-ANCA-associated granulomatosis with polyangiitis superimposed on post-streptococcal acute glomerulonephritis

An eight-year-old girl was admitted with vomiting, gross hematuria, and progressive renal dysfunction. A renal biopsy revealed endocapillary proliferative glomerulopathy and crescent formation. Immunofluorescence staining revealed diffuse granular deposits of IgG and C3. Post-streptococcal acute glomerulonephritis (PSAGN) was suspected, based on the elevated anti-streptolysin O levels, decreased serum C3 concentrations, and histologic findings. The myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA) test was positive, and the young patient gradually developed palisaded neutrophilic and granulomatous dermatitis (PNGD), orbital and paranasal sinus granulomatous neoplasms, along with intermittent nose, head, and orbital pain. Finally, she was diagnosed with the rare MPO-ANCA-associated granulomatosis with polyangiitis (GPA) superimposed on PSAGN. The patient was treated with aggressive renal replacement therapy, methylprednisolone pulse therapy, and intravenous pulse cyclophosphamide; her renal function normalized, and her pain symptoms improved.

Limited Antineutrophil Cytoplasmic Antibodies (ANCA)-Negative Granulomatosis With Polyangiitis: Successful Response to Rituximab

Granulomatosis with polyangiitis (GPA), a systemic vasculitis, is commonly characterized by the presence of antineutrophil cytoplasmic antibodies (ANCA). However, a subset of patients with limited disease may exhibit ANCA negativity. In this article, we report the case of a 40-year-old female diagnosed with GPA with intolerance to methotrexate titration and glucocorticoid therapy, leading to the initiation of rituximab treatment. Subsequently, the patient exhibited sustained clinical, laboratory, and radiological improvement. The identification of limited GPA has important therapeutic implications as the effectiveness of the medical treatment in ANCA-negative GPA may differ. Rituximab has emerged as an optimal treatment, irrespective of ANCA status, offering prolonged responses and a favorable tolerance profile in these patients.

Total Globulin Fraction at Diagnosis Could Forecast All-Cause Mortality during the Disease Course in Patients with Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

Total globulin fraction (TGF) is calculated by subtracting serum albumin levels from serum total protein levels. The present study examined whether TGF at diagnosis could forecast all-cause mortality during the disease course in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). The present study included 283 patients with AAV. The variables at AAV diagnosis such as demographic data, AAV-specific data including the Birmingham vasculitis activity score (BVAS), five-factor score (FFS), and laboratory data including ANCA, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were collected. The number of deceased patients during the follow-up duration based on all-cause mortality was counted. The median age of the 283 AAV patients was 60 years, and 35.7% were men. ANCAs were detected in 228 patients, and the median TGF was 2.9. A total of 39 patients (13.8%) died within a median follow-up duration of 46.9 months. TGF at AAV diagnosis was significantly correlated with ESR and CRP rather than AAV activity. Patients with ANCA positivity exhibited a significantly higher median TGF at AAV diagnosis than those without. Patients with TGF ≥ 3.1 g/dL at AAV diagnosis exhibited a significantly lower cumulative survival rate than those without. Furthermore, in the multivariable Cox hazards model analysis, TGF ≥ 3.1 g/dL (hazard ratio 2.611) was independently associated with all-cause mortality, along with age, male sex, and body mass index. The present study is the first to demonstrate that TGF at AAV diagnosis can forecast all-cause mortality during the disease course in AAV patients.

Differential diagnosis of pulmonary sarcoidosis: a review

Diagnosing pulmonary sarcoidosis raises challenges due to both the absence of a specific diagnostic criterion and the varied presentations capable of mimicking many other conditions. The aim of this review is to help non-sarcoidosis experts establish optimal differential-diagnosis strategies tailored to each situation. Alternative granulomatous diseases that must be ruled out include infections (notably tuberculosis, nontuberculous mycobacterial infections, and histoplasmosis), chronic beryllium disease, hypersensitivity pneumonitis, granulomatous talcosis, drug-induced granulomatosis (notably due to TNF-a antagonists, immune checkpoint inhibitors, targeted therapies, and interferons), immune deficiencies, genetic disorders (Blau syndrome), Crohn's disease, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and malignancy-associated granulomatosis. Ruling out lymphoproliferative disorders may also be very challenging before obtaining typical biopsy specimen. The first step is an assessment of epidemiological factors, notably the incidence of sarcoidosis and of alternative diagnoses; exposure to risk factors (e.g., infectious, occupational, and environmental agents); and exposure to drugs taken for therapeutic or recreational purposes. The clinical history, physical examination and, above all, chest computed tomography indicate which differential diagnoses are most likely, thereby guiding the choice of subsequent investigations (e.g., microbiological investigations, lymphocyte proliferation tests with metals, autoantibody assays, and genetic tests). The goal is to rule out all diagnoses other than sarcoidosis that are consistent with the clinical situation. Chest computed tomography findings, from common to rare and from typical to atypical, are described for sarcoidosis and the alternatives. The pathology of granulomas and associated lesions is discussed and diagnostically helpful stains specified. In some patients, the definite diagnosis may require the continuous gathering of information during follow-up. Diseases that often closely mimic sarcoidosis include chronic beryllium disease and drug-induced granulomatosis. Tuberculosis rarely resembles sarcoidosis but is a leading differential diagnosis in regions of high tuberculosis endemicity.

Characteristics of ANCA-associated vasculitis with aneurysms: Case series and review of the literature

INTRODUCTION

ANCA-associated vasculitis (AAV) is an exceptional cause of small and large vascular aneurysms. Here, we present the phenotypic characteristics of patients with AAV associated with the presence of aneurysms.

METHODS

We conducted a retrospective multicenter study and a systematic review of the literature. Only AAV patients with positive ANCA results and > 1 aneurysm(s) were enrolled. Patients were recruited through a call of observations among the French Vasculitis Study Group (FVSG) and the French Internal Medicine Network. Patients with aneurysm rupture were compared to those without.

RESULTS

We enrolled 51 patients in the cohort, including 31 (67%) with granulomatosis with polyangiitis. The median Birmingham Vasculitis Activity Score was 18 [6-41]. A total of 92 aneurysms were noted, 74% of which involved medium-sized arteries, particularly the renal artery. During a follow-up of 24 [6-56] months, 22 (43%) patients experienced aneurysmal rupture, 91% of which involved medium-sized vessels. Patients with aneurysmal rupture showed significantly more pulmonary infiltrates and higher creatinine levels at baseline than patients without rupture. Initial treatments did not differ between the two groups. Ten (20%) patients died during the follow-up, including three from an aneurysmal rupture.

CONCLUSION

Aneurysms were more frequently observed in GPA patients and predominantly affected medium-sized vessels, especially the renal arteries. The risk of rupture was high and occurred in >40% of patients. Because of their increased mortality, further studies are required to better manage this subset of patients.

A Runny Nose Leads to a Rare Diagnosis: Chronic Sinusitis as a Sole Manifestation of Limited Granulomatosis With Polyangiitis

Granulomatosis with polyangiitis (GPA) is an antineutrophil cytoplasmic antibody (ANCA)-associated necrotizing vasculitis of small to medium-sized blood vessels. The typical presentation is the classic triad of upper airway, pulmonary, and renal involvement. However, it can rarely present with the involvement of a single organ system known as limited granulomatosis with polyangiitis. We present a case of a 53-year-old male with chronic rhinosinusitis as the only manifestation of limited GPA. The diagnosis was established incidentally based on biopsy findings from the paranasal sinuses obtained during functional endoscopic sinus surgery. Subsequent testing revealed a positive cytoplasmic antineutrophilic antibody. No evidence of systemic involvement was noted. Prednisone and azathioprine were initiated leading to significant improvement. Although upper respiratory tract involvement is common in GPA, it is rare for the condition to be limited to this organ system. Our case of limited GPA is distinct in that it represents a rare presentation of this already rare disease.

Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis (AAV) Masquerading As Mononeuritis Multiplex: A Case Report

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of disorders that causes severe small-vessel inflammation with systemic manifestations. There are three subtypes of AAV, namely granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic GPA (EGPA). The most commonly affected organs are the upper and lower respiratory tract and the kidneys with occasional and varied neurological manifestations. Here we report a case of a 61-year-old female who presented with a one-month history of numbness, paresthesia, and asymmetric distal weakness of both lower limbs without any bladder or bowel involvement. Similar complaints appeared in her upper limbs three days prior to admission. She also suffered from myalgia, arthralgia, reduced appetite, and lost 8-10 kg weight over the past six months. Her nerve conduction study (NCV) revealed asymmetrical, predominantly motor, mixed, axonal and demyelinating polyneuropathy affecting both lower limbs, which was suggestive of mononeuritis multiplex. After a detailed workup, she tested strongly positive for cytoplasmic ANCA (c-ANCA). Although there was no clinical involvement of the respiratory tract, a contrast-enhanced computed tomography scan of the thorax and abdomen showed multifocal subpleural and lung parenchymal soft tissue lesions and mediastinal and bilateral hilar lymphadenopathy suggestive of a granulomatous lesion. She was diagnosed with the GPA variant of ANCA-associated vasculitis. Remission induction was achieved with high-dose methylprednisolone and cyclophosphamide along with alternate-day cotrimoxazole. Remission was maintained with tapering doses of steroid and mycophenolate mofetil with a slow but sustained recovery. On follow-up after one year, she walked without support with mild residual burning paresthesia in both feet. This case highlights the fact that neurological symptoms can be the presenting manifestation of AAV, and clinicians should have a high level of suspicion for AAV in patients presenting with mononeuritis multiplex, especially after ruling out common causes. By considering such etiologies, it may be possible to diagnose the condition at an earlier stage and initiate treatment to prevent potential pulmonary or renal damage.

Cutaneous Deep Ulcerations as Initial Presentations of Granulomatosis with Polyangiitis: Two Case Reports and Differential Diagnosis

Background: Granulomatosis with polyangiitis (GPA) is an antineutrophil-cytoplasmic-antibody (ANCA)-associated small-vessel vasculitis characterized by necrotizing granulomatous inflammation. Symptoms of skin involvement can appear in 30–50% of patients with GPA, and may present as the initial presentation. Case Presentation: We describe two patients who presented with multiple deep, large, nonhealing skin ulcers postoperatively with purulent drainage and fever. Both patients were diagnosed with GPA after an extensive evaluation, including histopathology. Infectious, connective tissue disease and malignant etiologies were excluded. Their cANCA and PR3-ANCA levels were positive. Patient 2 was diagnosed early and recovered well after treatment with corticosteroids and rituximab; however, Patient 1 had a poor prognosis due to a long disease course. Conclusions: Diseases with multiple deep, large skin ulcers and fever can be infectious or noninfectious. Atypical manifestations may lead to missed diagnosis and misdiagnosis. GPA may initially present in a localized form before progressing to a generalized disease. The two cases we have highlighted will prompt clinicians to nevertheless call for a low threshold for diagnosis.

Monocular Vision Loss in a Patient With Earache and Night Sweats

A 62-year-old patient with a history of painless vision loss in her right eye, right ear pain and fullness, discomfort over her frontal and maxillary sinuses, nasal congestion without discharge, drenching night sweats, cramps in her quadriceps, and weight loss presented to the ophthalmology department. Examination revealed normal tympanic membranes and a dry but otherwise normal nasal mucosa on flexible endoscopy. What would you do next?

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

Background

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.

Methods

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.

Results

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).

Conclusion

HLA-class II is associated not only with susceptibility to MPO-AAV but also with risk of relapse in the Japanese population.

Classification and epidemiology of vasculitis: Emerging concepts

The recent publication of the American College of Rheumatology (ACR)-European Alliance of Associations for Rheumatology (EULAR) classification criteria for large vessel vasculitis and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) has provided modern criteria for the classification of these conditions, which incorporate contemporary methods of investigation and diagnosis. Further validation is required in independent cohorts, especially from populations that were not well represented in the development cohort. Studies of the occurrence of large vessel vasculitis report that Takayasu arteritis is a rare disease in most populations, and giant cell arteritis is the most common vasculitis in older populations. The incidence of AAV appears to have plateaued, but the prevalence is increasing as a result of lower mortality. The new classification criteria may affect the reported incidence and prevalence, and studies will be needed to confirm this. The impact of COVID-19 on the occurrence of the vasculitides is not completely known, but there is evidence of reduced occurrence of Kawasaki disease and IgA-associated vasculitis following lockdowns with reduced transmission of possible trigger infectious agents.

Polyangiitis overlap syndrome: a rare clinical entity

Polyangiitis overlap syndrome is a rare clinical entity comprising patients with overlapping features of more than one vasculitis, usually eosinophilic granulomatosis with polyangiitis (EGPA) and granulomatosis with polyangiitis (GPA). Few cases of polyangiitis overlap syndrome have been described in the literature, mostly associated with c-ANCA, anti-proteinase (PR)-3 positivity, a protean clinical picture characterized by vasculitis, eosinophilia and eosinophilic infiltrates in tissues and a favorable response to steroids and immunosuppressant treatments. Herein, we present a case of a 66-year-old woman with nasal obstruction, external nose deformity, sensorineural hearing loss, peripheral blood eosinophilia, high titer anti-PR3 antibodies and lung involvement. Nasal septum biopsies showed inflammatory infiltrate with eosinophilic component; histopathology of the lung demonstrated necrotizing granulomas associated with inflammatory infiltrate composed of numerous neutrophils and some eosinophils. The patient was diagnosed with polyangiitis overlap syndrome and successfully treated with cyclophosphamide. Recognizing this entity is fundamental given the distinct clinical phenotype and outcomes to therapy in the complex scenario of ANCA-associated vasculitides.

Unmet needs in ANCA-associated vasculitis: Physicians' and patients' perspectives

In recent years, clinical research has increased significantly and therapies for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis have improved. However, there are still unanswered questions and unmet needs about AAV patients. The purpose of this review is to examine the frontiers of research related to emerging biomarkers eventually predicting relapse, and new therapeutic approaches, not to mention new quality of life assessment tools. Identifying predictors of relapse may help optimize therapeutic strategies, minimize disease recurrence, and reduce treatment-related side effects. In addition, it is important to recognize that patients may suffer long-term consequences of the disease and its treatment, which, although life-saving, is often associated with significant side effects. Our goal, therefore, is to highlight what has been achieved, the pitfalls, and what still needs to be done, comparing the views of physicians and patients.

Differential diagnosis of a local form of granulomatosis with polyangiitis: nasal cavity and paranasal sinuses lesions (part 1)

Granulomatosis with polyangiitis (GPA) is a primary vasculitis associated with antineutrophil cytoplasmic antibodies, characterized by necrotizing vasculitis with predominant involvement of small vessels of various localizations and necrotizing granulomatous inflammation with multiple clinical manifestations. GPA remains one of the most severe systemic vasculitis with unfavorable prognosis. When analyzing the course of the disease, there are two variants of GPA, local (with lesions of the upper respiratory tract, URT, organs of vision and hearing) and generalized (with lesions of the URT, organs of vision and hearing in combination with the lungs and/or kidneys, gastrointestinal tract, nervous systems, skin involvement).The article discusses the differential diagnosis of the disease with the nasal cavity and paranasal sinuses lesions onset, which requires an interdisciplinary approach and interaction of doctors of different specialties.

Coexistence of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and IgA nephropathy

Co-occurrence of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and IgA nephropathy (IgAN) is extremely uncommon. To date, only a few case reports have described such patients. Here, we describe the clinical presentation, pathologic features, treatment response, and outcome data of five patients with the rare form of co-existing AAV and IgAN and compared the characteristics of these patients to AAV patients with pauci-immune glomerulonephritis (n = 10) and IgAN patients (n = 10) that were selected as controls by stratified random sampling. In addition, we summarize all the previously reported cases of AAV and IgAN. In total, including the current study, 16 AAV/IgAN overlap cases were reported. Our five patients with the coexistence of AAV and IgAN were younger than the ten AAV patients with pauci-immune glomerulonephritis (22.6 ± 8.2 years versus 48.9 ± 15.7 years, respectively, P = 0.004). Histologically, they had a significantly lower percentage of glomeruli with fibrous crescents compared with AAV patients (0.0% versus 4.0%, P = 0.038). Compared with ten IgAN patients, our five AAV/IgAN patients had higher levels of ESR (P = 0.032) and CRP (P = 0.031). After accepting treatment with a combination of steroid and immunosuppressants, all patients showed a positive response to therapy, except for one patient in our cohort and another previously reported patient. We described the clinical presentation, pathologic features, treatment response, and outcome data of five patients with overlapping AAV and IgAN. They had mild glomerular pathological lesions and a positive response to aggressive immunosuppressive therapy. They were quite similar to pauci-immune AAV patients in clinical features, except for younger age. They had a lower percentage of glomeruli with fibrous crescents compared with AAV patients. In contrast to IgAN patients, they had higher levels of ESR and CRP. The mechanism of the coexistence of IgAN and AAV needs further study.

The Reclassification of Patients With Previously Diagnosed Eosinophilic Granulomatosis With Polyangiitis Based on the 2022 ACR/EULAR Criteria for Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

OBJECTIVE

The American College of Rheumatology (ACR) and the European Alliance of Associations for Rheumatology (EULAR) have proposed the 2022 classification criteria for eosinophilic granulomatosis with polyangiitis (EGPA). This study applied the 2022 ACR/EULAR criteria to Korean patients with previously diagnosed EGPA to investigate the concordance rate between the 2022 ACR/EULAR criteria and the old criteria for EGPA.

METHODS

In total, 51 patients with EGPA who met the 1990 ACR criteria, the 2007 European Medicines Agency algorithm, and the 2012 Chapel Hill Consensus Conference definitions were reclassified based on the 2022 ACR/EULAR criteria.

RESULTS

Of 51 patients, 44 (86.3%) were reclassified as having EGPA according to the 2022 ACR/EULAR criteria. Among the 7 patients who failed to meet the 2022 ACR/EULAR criteria, 3 patients were reclassified as having microscopic polyangiitis (MPA) and 1 was reclassified as having granulomatosis with polyangiitis (GPA) based on the 2022 ACR/EULAR criteria; as well, 3 patients were reclassified as having unclassifiable vasculitis. Moreover, 6 patients who met the 2022 ACR/EULAR criteria for EGPA simultaneously met the criteria for MPA based on the 2022 ACR/EULAR criteria for MPA, and 1 who met the criteria for EGPA simultaneously met the criteria for GPA based on the 2022 ACR/EULAR criteria for GPA.

CONCLUSION

The concordance rate between the 2022 ACR/EULAR criteria for EGPA and the old criteria was 86.3%. The most important factor in the failure to reclassify patients as having EGPA was the exclusion of nonfixed pulmonary infiltrates in the 1990 ACR criteria for EGPA. We cautiously suggest reconsidering nonfixed pulmonary infiltrates in cases reclassified as unclassifiable vasculitis. Further, additional classification strategies are needed for patients who simultaneously satisfy both antineutrophil cytoplasmic antibody-associated vasculitis subtypes.

The eye is a common site of granulomatosis with polyangiitis. A collaborative study

BACKGROUND

Ocular manifestations of granulomatosis with polyangiitis (GPA) have been reported in a limited number of studies and with largely variable frequency. Here we report on the clinical, diagnostic, and therapeutic features of a cohort of 63 GPA patients, with particular regard to 22 of them with ophthalmic involvement (35%).

METHODS

Clinical manifestations, results of immunological findings, histopathological pictures, imaging data, Birmingham Vasculitis Activity Score, therapeutic regimens, and outcomes were retrospectively analyzed. At diagnosis, in addition to a structured clinical assessment, all patients underwent a comprehensive ophthalmologic examination.

RESULTS

The most frequently involved organs were kidneys, lungs, ear/nose/throat, and eyes. Ocular manifestations were bilateral in 32%. The three most commonly diagnosed ophthalmologic manifestations were scleritis (36%), retro-orbital pseudotumor or orbital mass (23%), and episcleritis (13%). Ocular and systemic involvement were simultaneously present at onset in 41% of the patients; systemic involvement was followed by ocular lesions in 36%; ocular inflammation was followed by systemic manifestations in 18%; and an orbital mass in the absence of systemic disease characterized 5%. Glucocorticoids plus cyclophosphamide and glucocorticoids plus rituximab were the combined therapies most frequently employed during remission induction and remission maintenance, respectively. Persistent ophthalmologic and extra-ocular remissions were achieved in 77 and 64% of the patients, respectively. One to three systemic relapses were diagnosed in 7 patients (31.8%). At the last follow-up, a visual outcome 20/40 or better in 31 (70%) of 44 eyes was determined.

CONCLUSIONS

The eye was involved in over one third of our patients with GPA. Increased awareness, early diagnosis, and multi-specialty collaboration are critical in achieving a favorable outcome of GPA.

Polyautoimmunity in systemic lupus erythematosus patients: New insights from a cross-sectional study

Objective

To assess the frequency of polyautoimmunity (PolyA) in a cohort of Colombian patients with systemic lupus erythematosus (SLE) and to identify associated factors.

Methods

This is an analytical cross-sectional study in a specialized center., a comprehensive review of the medical records of SLE patients was performed from 2015 to 2020 in order to obtain demographic, clinical data, laboratory, and treatment information. Associations between PolyA, demographic, and characteristics of the disease were explored.

Results

A total of 463 patients were included in the analysis. The average age was 47.3 ± 15 years. Most of this population were female (87.4%), whom were diagnosed with SLE in a long-term SLE (10.6 ± 10.1 years). Out of the total patients, 34.7% were diagnosed with PolyA. Among the most frequent clinical criteria for SLICC, arthritis (65%), kidney impairment (39.5%), and alopecia (34.8%) were found. The most frequent SLE-associated PolyA were antiphospholipid syndrome (APS) and Sjögren's syndrome (SS) (16.63% and 10.58%, respectively). PolyA-associated factors were age, xerophthalmia, central nervous system occlusion, and deep vein thrombosis (DVT). In contrast, renal impairment was significantly less frequent in PolyA patients after multivariate analysis.

Conclusion

The results have showed associated factors with PolyA like age, xerophthalmia, central nervous system occlusion, and deep vein thrombosis in this cohort. On the other hand, lupus nephritis was less frequent in patients with PolyA. This study provides a spotlight of a specific SLE population as real-life evidence for a better characterization of PolyA in the future.

Sinonasal Amoebiasis: An Unexpected Cause of Sinonasal Necroinflammatory Disease

While amoebic infection is widely known as a cause of gastroenteritis, keratitis, and meningoencephalitis, amoebae are challenging to recognize at unexpected sites. Despite multiple case reports of sinonasal amoebiasis, amoebic infection is not regularly considered in the differential diagnosis of sinonasal necroinflammatory disease. Here, we aim to characterize the pathologic features of sinonasal amoebiasis to facilitate better recognition. We identified sinonasal amoebiasis in 4 men, median age of 67 years (range: 37 to 71 y). All were immunocompromised, including 2 with chronic lymphocytic leukemia, 1 with human immunodeficiency virus, and 1 with human immunodeficiency virus and kidney transplant. Patients presented with nasal mucosal necrosis or polypoid masses, with facial ulceration in 1 patient and distant dermal nodules in another. Biopsies displayed extensive necrotic debris and inflammation. Although amoebic cysts were abundant in 3 cases, they were mistaken for yeast at frozen section in 1 case; 1 case showed only rare trophozoites that were not recognized on initial biopsy. Periodic acid Schiff and Grocott Methenamine Silver stains highlighted the organisms, and polymerase chain reaction confirmed Acanthamoeba species in 3 cases tested. 2 patients responded well to antiprotozoal medications, but 2 died of disease. Overall, sinonasal amoebiasis presents as a necroinflammatory process in patients immunocompromised for various reasons. Amoebae can mimic other organisms or be incredibly scarce, requiring active consideration to recognize amoebiasis and differentiate it from overlapping conditions like invasive fungal sinusitis, granulomatosis with polyangiitis, and natural killer/T-cell lymphoma. Because sinonasal amoebiasis is highly treatable when diagnosed promptly, pathologists play a critical role in the recognition of this rare necroinflammatory disease.

Targeting immune checkpoints in anti-neutrophil cytoplasmic antibodies associated vasculitis: the potential therapeutic targets in the future

Anti-neutrophil cytoplasmic autoantibodies (ANCA) associated vasculitis (AAV) is a necrotizing vasculitis mainly involving small blood vessels. It is demonstrated that T cells are important in the pathogenesis of AAV, including regulatory T cells (Treg) and helper T cells (Th), especially Th2, Th17, and follicular Th cells (Tfh). In addition, the exhaustion of T cells predicted the favorable prognosis of AAV. The immune checkpoints (ICs) consist of a group of co-stimulatory and co-inhibitory molecules expressed on the surface of T cells, which maintains a balance between the activation and exhaustion of T cells. CD28, inducible T-cell co-stimulator (ICOS), OX40, CD40L, glucocorticoid induced tumor necrosis factor receptor (GITR), and CD137 are the common co-stimulatory molecules, while the programmed cell death 1 (PD-1), cytotoxic T lymphocyte-associated molecule 4 (CTLA-4), T cell immunoglobulin (Ig) and mucin domain-containing protein 3 (TIM-3), B and T lymphocyte attenuator (BTLA), V-domain Ig suppressor of T cell activation (VISTA), T-cell Ig and ITIM domain (TIGIT), CD200, and lymphocyte activation gene 3 (LAG-3) belong to co-inhibitory molecules. If this balance was disrupted and the activation of T cells was increased, autoimmune diseases (AIDs) might be induced. Even in the treatment of malignant tumors, activation of T cells by immune checkpoint inhibitors (ICIs) may result in AIDs known as rheumatic immune-related adverse events (Rh-irAEs), suggesting the importance of ICs in AIDs. In this review, we summarized the features of AAV induced by immunotherapy using ICIs in patients with malignant tumors, and then reviewed the biological characteristics of different ICs. Our aim was to explore potential targets in ICs for future treatment of AAV.

A Diagnostic Dilemma of a Case of Granulomatosis With Polyangiitis (GPA) Presenting With Thrombotic Vasculopathy

Granulomatosis with polyangiitis (GPA) is a rare disease with a prevalence of about three in 100,000 persons in the United States. GPA is an antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis affecting predominantly small-sized vessels. It can present with localized or systemic symptoms with multiple organ involvement, thus making diagnosis challenging. Common skin lesions in GPA are palpable purpura, petechiae, ulcers, and livedo reticularis. These lesions usually have underlying vasculitis with or without granuloma on histology findings. To date, there have been no previous reports about thrombotic vasculopathy in GPA before. We present a case of a 25-year-old female who presented with intermittent joint pain for weeks, purpuric rash, and mild hemoptysis for a few days. A review of systems was notable for a 15-pound weight loss in one year. Physical examination was significant for a purpuric rash on the left elbow and toe, and left knee swelling and erythema. Presenting laboratory results were notable for anemia, indirect hyperbilirubinemia, mildly elevated D-dimers, and microscopic hematuria. Chest radiograph revealed confluent airspace disease. Extensive infectious workup was negative. A skin biopsy of her left toe revealed dermal intravascular thrombi without evidence of vasculitis. The thrombotic vasculopathy did not favor vasculitis but raised concern for a hypercoagulable state. However, extensive hematologic workup was negative. Bronchoscopy findings were consistent with diffuse alveolar hemorrhage. Later, cytoplasmic ANCA (c-ANCA) and anti-proteinase 3 (PR3) antibody titers were positive. Her diagnosis was unclear since both skin biopsy and bronchoscopy were nonspecific and inconsistent with her positive antibody results. The patient eventually underwent a kidney biopsy, which showed pauci-immune necrotizing and crescentic glomerulonephritis. Finally, a diagnosis of granulomatosis with polyangiitis was made based on the kidney biopsy and positive c-ANCA. The patient was treated with steroids and IV rituximab and discharged home with outpatient rheumatology follow-up. Due to multiple signs and symptoms including thrombotic vasculopathy, there was a diagnostic dilemma requiring a multidisciplinary approach. This case highlights the importance of pattern recognition for the diagnostic framework of rare disease entities and the multidisciplinary collaborative efforts required to reach the final diagnosis.

Comparison of the 2022 ACR/EULAR Classification Criteria for Antineutrophil Cytoplasmic Antibody-Associated Vasculitis with Previous Criteria

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) comprises group of small vessel vasculitides, including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). In 2022, the American College of Rheumatology (ACR) and the European Alliance of Associations for Rheumatology (EULAR) jointly proposed new classification criteria for AAV (the 2022 ACR/EULAR criteria). In this review, we briefly summarize the 2022 ACR/EULAR criteria for GPA, MPA, and EGPA, and introduce our clinical experience with applying them to patients who were previously diagnosed with AAV based on three criteria: firstly, the classification criteria for GPA and EGPA proposed by the ACR in 1990; secondly, the algorithm for the classification of AAV and polyarteritis nodosa proposed by the European Medicines Agency algorithm in 2007 (the 2007 EMA algorithm); and thirdly, the revised International Chapel Hill Consensus Conference nomenclature of vasculitides in 2012 (the 2012 CHCC definitions). We found that concordance rate was highest in patients with MPA (96.6%), followed by those with EGPA (86.3%) and GPA (73.8%). In addition, compared to previous criteria, we noted several issues of the undervalued or overvalued items in the 2022 ACR/EULAR criteria for classifying AAV and provided several suggestions. To increase the diagnostic accuracy and reduce the discordance rate among the new and previous criteria for AAV, we suggest that the previous criteria should be considered together with the 2022 ACR/EULAR criteria when applying the classification criteria for AAV to patients suspected of AAV.

Cutaneous Small Vessel Vasculitis: A Practical Guide to Diagnosis and Management

Cutaneous vasculitis may be a cutaneous manifestation of systemic vasculitis, a skin-limited variant of systemic vasculitis, or a type of single-organ vasculitis limited to the skin. Careful evaluation is necessary to distinguish these possibilities, differentiate skin-limited from systemic disease, and identify important underlying conditions, if present. Appropriate management depends on disease type and severity. In the case of cutaneous small vessel vasculitis (CSVV), treatment is primarily based on case reports and expert opinion, using a range of immunomodulatory or immunosuppressive therapies. This manuscript presents a systematic and stepwise approach to the evaluation of patients presenting with cutaneous vasculitis, as well as the management of those diagnosed with CSVV, using best available evidence. Studies relevant to the classification, evaluation, and management of skin vasculitis are ongoing.

Gastrointestinal Hemorrhage With Gastritis and Pancolitis as the Sole Presentation for Granulomatosis With Polyangiitis Flare

Granulomatosis with polyangiitis (GPA), previously known as Wegener granulomatosis, is a rare small vessel vasculitis affecting mainly Whites. The prevalence of GPA in the United States is estimated to be 3 of 100,000 individuals. Classically, GPA affects upper airways, lungs, and kidneys, with the upper airways being the most common site. Occasionally, other organs affected by GPA include eyes, skin, joints, and the nervous system. The gastrointestinal system is rarely affected; however, some cases have been reported. In this case report, we present a patient with hemorrhagic gastritis and pancolitis consistent with GPA and discuss features from the literature of gastrointestinal manifestations in patients with GPA.

Favourable outcome of acute hepatitis E infection in patients with ANCA-associated vasculitis

BACKGROUND

Hepatitis E virus (HEV) infection is a frequent cause of acute viral hepatitis. Immunocompromised patients are at increased risk for viral infection and chronic courses of hepatitis. Whether patients with autoimmune diseases are at risk of developing clinically relevant hepatitis or even chronic liver disease after HEV infection is discussed controversially. ANCA-associated vasculitis is a rare autoimmune disease with potentially life-threatening organ involvement, thus requiring intensive immunosuppression with glucocorticoids, cyclophosphamide, or rituximab. As there are no reports available on the infection with HEV in patients with ANCA-associated vasculitis, clinical decision making in such cases is based on experiences from other disease entities. Therefore, in this study we analyzed the course of liver disease and the therapeutic management of autoimmune vasculitis in a retrospective cohort of five patients with ANCA-associated vasculitis and acute hepatitis E.

RESULTS

Four patients were on immunosuppressive maintenance therapy and one patient was on remission induction therapy with cyclophosphamide and high dose glucocorticoids. All patients had at least one potentially hepatotoxic co-medication at the time of hepatitis. Hepatitis-associated clinical symptoms were recorded in four of five patients. The course of hepatitis was characterized by strongly elevated transaminases, a temporary liver failure was observed in one case. The management of hepatitis E included cessation of the immunosuppressants in all patients, whereas oral glucocorticoids were not discontinued. Under this regime, all patients cleared the virus without additional anti-viral treatment. Liver enzymes normalized one month after they peaked. In the follow-up period of at least 1.5 years (range 1.5-12 years), no chronic liver disease was observed, although one patient died of cholangiocarcinoma with liver metastases some years after HEV infection. Vasculitis was not active in our patient cohort at the time of HEV infection. However, inflammatory flares occured in three of five patients after discontinuation of the immunosuppressive therapy. Immunosuppressants were paused for a median time of 4 weeks and after their resumption vasculitic disease activity was controlled in all patients.

CONCLUSIONS

Acute HEV infection in patients with ANCA-associated vasculitis shows a favorable outcome of liver disease but bears the risk of inflammatory flares due to cessation of immunosuppression.

Granulomatous polyangiitis misdiagnosed as hematogenous lung abscess: A case report

Granuloma polyangiitis (GPA) is a necrotizing granulomatous inflammation, which is a systemic autoimmune disease that mainly affects the upper respiratory tract, lungs, and kidneys. Clinically, the clinical manifestations of GPA vary greatly, and it is extremely easy to be misdiagnosed. We report a 60-year-old man with granulomatous polyangiitis with dysuria and parotid gland enlargement as the first symptom. As the condition worsened, he gradually developed symptoms in multiple systems such as persistent high fever, nosebleeds, hemoptysis, skin rash, and multiple cavities in the lungs. Due to high fever, hemoptysis, and the gradual expansion of lung cavities, the suspected hematogenous lung abscess was not well controlled and transferred to the respiratory department. The manifestation of involvement was finally confirmed by skin biopsy. Biopsy was performed on the skin of the lower extremities with a dark red rash with multiple microprojections. Pathology indicated neutrophilic infiltration and necrosis of small vessel walls, and granuloma formation. Blood anti-protease 3 antibody (PR3) was positive Monotherapy with prednisone. Body temperature gradually returned to normal; hemoptysis and nasal bleeding disappeared; parotid gland enlargement and dysuria relieved, and lung cavities gradually reduced. When anti-infective treatment is ineffective, we should consider the presence of some non-infectious diseases, especially when multiple systems are involved; biopsy should be performed as soon as possible. Granulomatous polyangiitis has various manifestations. Parotid glands and prostate may also be the first organs involved, not limited to common targets such as the respiratory tract and kidneys.

Adult case of chronic granulomatous disease mimicking granulomatosis with polyangiitis

BACKGROUND

This article presents a patient who was initially diagnosed as having granulomatosis with polyangiitis (GPA), and was later diagnosed as having chronic granulomatous disease (CGD) in adulthood. We aimed to raise awareness of CGD, which can be confused with rheumatic diseases.

CASE REPORT

We present a 33-year-old male patient with CGD with recurrent opportunistic bacterial and fungal infections who was diagnosed as having GPA, and had a history of recurrent lung infections and brain abscesses since childhood. The patient, who had cavitary lesions in the lung and mucosal lesions in the nose, was diagnosed as having GPA based on antineutrophil cytoplasmic antibody positivity. CGD was suspected in his last hospitalization after the patient underwent a nitro blue tetrazolium test. Accordingly, neutrophil oxidative function was tested using a dihydrorhodamine assay, which confirmed CGD. Molecular analysis of the patient revealed that the NCF1 gene had a GT deletion at the beginning of exon 2. Our patient was diagnosed as having late-onset CGD; he is currently well and taking antibiotic prophylaxis.

CONCLUSION

As a result of the altered humoral immune response in CGD, there is unregulated inflammation and sustained antigen stimulation. This excessive inflammatory response can be confused with autoimmune diseases and cause delays in diagnosis. This case is important in the differential diagnosis of CGD in adult patients with recurrent opportunistic infections.

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

Introduction

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

Methods

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

Results

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

Conclusions

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