The paper presents a clinical case of MPA in a 67-year-old woman following COVID-19, characterized by significant difficulties when working with the early etiological verification of diagnosis. The patient presented with polyarthritis affecting the upper and lower limbs, fever, and comorbid urological pathology in the form of urolithiasis and recurrent cystitis. This clinical presentation, hyperuricemia, azotaemia and anemia were mistakenly interpreted as chronic kidney disease: gouty nephropathy, gouty arthritis, which masked the underlying disease for a long time delaying the timely MPA diagnosis and treatment. Given that MPA is a multisystemic disease, it is essential to enhance awareness and knowledge of healthcare professionals of various specialties regarding AAVs and MPA in particular, as evidenced by the online survey data during COVID-19 pandemic among doctors in 21 countries.

Antineutrophil cytoplasmic autoantibody associated vasculitides has 3 different types: Granulomatosis with polyangiitis, eosinophilic granulomatosis and polyangiitis and microscopic polyangiitis. These vasculitides manifest differently based on which area of small and medium size vessels in our bodies that it affects. In this case report, we discuss a unique case of microscopic polyangiitis diagnosed in a 75-year-old male who was relatively asymptomatic i.e. indolent, apart from nodules present in the lung with the use of the diagnostic criteria outlined by 2022 American College of Rheumatology and European Alliance of Associations for Rheumatology. In addition, we reviewed briefly about vasculitis, its epidemiology and the workup of microscopic polyangiitis.

Vasculitis, a group of systemic inflammatory diseases that affect the cardiovascular (CV) system, presents with a variety of clinical manifestations that depend on the size of the affected blood vessels. While some types of vasculitis reveal distinct symptoms, others are characterized by more diffuse and nonspecific presentations that can result in delayed diagnosis and treatment initiation. Interestingly, patients with vasculitides share a significant comorbidity: an elevated CV risk, contributing to increased rates of CV events and mortality. This heightened risk is caused by cumulative inflammatory burden, traditional CV risk factors, medication effects, and reduced physical fitness. Traditional risk assessment tools, commonly used in the general population, frequently underestimate the CV risk in patients with inflammatory rheumatic conditions. Consequently, novel approaches are necessary to stratify the precise CV risk in vasculitis patients. A number of surrogate parameters for CV risk have been investigated, with arterial stiffness emerging as a promising marker. Pulse wave velocity (PWV) is a well-established method for assessing arterial stiffness and predicting CV risk across different populations. Among numerous PWV variants, carotid-femoral PWV (cfPWV) stands out as the most extensively studied and accepted reference standard. It has demonstrated its utility as a surrogate CV parameter both in the general population and in patients with systemic inflammatory rheumatic diseases. In recent years, research has expanded to assess arterial stiffness in systemic rheumatic diseases, such as arthritis, connective tissue diseases, rheumatologic overlap syndromes, and chronic pain disorders, using measurements of PWV and other markers of arterial compliance and elasticity. Despite burgeoning research in rheumatologic diseases, data on CV risk markers in vasculitides remain limited and fragmented. This narrative review aims to provide a comprehensive overview of arterial stiffness as a potential screening marker for CV diseases, atheromatosis, and ultimately CV risk among patients with vasculitides.

To summarise and update evidence to inform the 2022 update of the EULAR recommendations for the management of antineutrophil cytoplasm antibody-associated vasculitis (AAV).
A systematic literature review (SLR) was performed to identify current evidence regarding treatment of AAV. PubMed, EMBASE and the Cochrane library were searched from 1 February 2015 to 25 February 2022. The evidence presented here is focused on the treatment of granulomatosis with polyangiitis and microscopic polyangiitis.
3517 articles were screened and 175 assessed by full-text review. Ninety articles were included in the final evidence synthesis. Cyclophosphamide and rituximab (RTX) show similar efficacy for remission induction (level of evidence (LoE) 1a) but RTX is more effective in relapsing disease (LoE 1b). Glucocorticoid (GC) protocols with faster tapering result in similar remission rates but lower rates of serious infections (LoE 1b). Avacopan can be used to rapidly taper and replace GC (LoE 1b). Data on plasma exchange are inconsistent depending on the analysed trial populations but meta-analyses based on randomised controlled trials demonstrate a reduction of the risk of end-stage kidney disease at 1 year but not during long-term follow-up (LoE 1a). Use of RTX for maintenance of remission is associated with lower relapse rates compared with azathioprine (AZA, LoE 1b). Prolonged maintenance treatment results in lower relapse rates for both, AZA (LoE 1b) and RTX (LoE 1b).
This SLR provides current evidence to inform the 2022 update of the EULAR recommendations for the management of AAV.

Antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV), namely granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis and microscopic polyangiitis constitute a group of rare systemic vasculitides, affecting small vessels. Genders are equally affected, with symptoms most commonly presenting during and/or after the fifth decade of life, but AAV may also present in younger individuals. As advanced maternal age is becoming common and safe over the last decades, it is now more feasible for middle-aged women suffering from AAV to get pregnant. Although adverse pregnancy outcomes have been thoroughly investigated in other systemic diseases, the exact prevalence of pregnancy complications and unfavorable outcomes in pregnant women with AAV has not been systematically evaluated.
We researched PubMed, Scopus, Cochrane Library and Cinahl databases until September, 2022. Three blinded investigators extracted data and assessed the risk of bias. A random effects model was used for the analysis. The outcomes studied were pre-term delivery, intrauterine growth restriction (IUGR) neonates and disease flare.
We included six studies with 92 pregnancies in patients with AAV. The prevalence of pre-term delivery, IUGR neonates and disease flare were 18% (CI: 0.10-0.30, P=non-significant), 20% (CI: 0.11-0.33, P=non-significant) and 28% (CI: 0.09-0.59, P<0.01), respectively.
The analysis demonstrated higher occurrence of adverse outcomes in pregnant women suffering from AAV accompanied by an increased risk of disease flare during pregnancy. These findings underline the importance of preconception counseling and the necessity of close monitoring in these patients similarly to other systemic inflammatory diseases.

Interstitial lung disease is a common complication of anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). It is seen most commonly in microscopic polyangiitis owing to the pathogenic effect of myeloperoxidase in the lung. Oxidative stress, neutrophil elastase release, and expression of inflammatory proteins by neutrophil extracellular traps result in fibroblast proliferation and differentiation and therefore fibrosis. Usually, interstitial pneumonia pattern fibrosis is common and associated with poor survival. Treatment for patients with AAV and interstitial lung disease lacks evidence, and those with vasculitis are treated with immunosuppression, whereas those with progressive fibrosis may well benefit from antifibrotic therapy.

[This corrects the article DOI: 10.3389/fonc.2022.987507.].

Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV) is a multisystem disorder of small blood vessels subdivided into granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Oral manifestations (OMs) have been reported to include mucosal ulceration, gingival enlargement, alveolar bone necrosis, tooth loss, oro-antral communication, palatal perforation, parotitis, and candidal infection mainly in GPA. They may appear during the course of the disease, as a disease flare-up, or as the presenting sign. These OMs are often nonspecific and can mimic an array of conditions, therefore formulating a differential diagnosis can be challenging. This review updates the OMs of GPA, and, for the first, time includes OMs of other AAVs. It provides recommendations for the overall assessment and the diagnosis and management of all AAV OMs with considerations for treatment coordination. The role of oral health care providers in multidisciplinary care is highlighted.

Because of some similarities in organ involvement, clinical manifestations, and histopathological features, IgG4-related disease (IgG4-RD) may occur concurrently with some clinicopathologic variants of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). An overlap syndrome of IgG4-RD and AAV has recently been proposed in clinical and/or histopathological studies, indicating that there may be some potential pathophysiological associations between the two disease entities; however, the mechanisms underlying these are incompletely understood. Here, we describe a rare case of a 63-year-old man with IgG4-related tubulointerstitial nephritis (IgG4-TIN) and microscopic polyangiitis-associated glomerulonephritis (MPA-GN) overlap syndrome. The clinical diagnosis of MPA was based on the 2022 American College of Rheumatology (ACR)/European League Against Rheumatology (EULAR) classification criteria. Remission induction therapy with intravenous methylprednisolone was initiated, followed by oral prednisone maintenance therapy with gradual tapering. The patient remained asymptomatic and his renal function was essentially normalized within 3.5 months of follow-up. The serum IgG4 levels decreased to 5 g/L. We also conducted a literature review to identify clinical findings, treatment options, and outcomes of patients with concurrent IgG4-RD and MPA and briefly discussed the potential pathophysiological association between IgG4-RD and MPA. Our findings enrich the database of this rare overlap syndrome and provide a basis for the diagnosis and early intervention in both diseases. These results provide some insights for clinicians to recognize and treat this overlap syndrome.

UNASSIGNED: Microscopic polyangiitis (MPA) is a necrotizing vasculitis that involves small- and medium-sized vessels and is associated with the presence of antineutrophil cytoplasmic antibodies with a perinuclear staining pattern (p-ANCA). The kidney and lungs are the organs primarily affected. MPA is rare in children and is easily misdiagnosed. Below is a complete case history of the course of the disease.
UNASSIGNED: An 11-year-old girl with a 1-month history of cough and hemoptysis showed no improvement after imipenem-cilastatin treatment. p-ANCA and microscopic hematuria and proteinuria were positive, and a chest CT revealed an area of shadow in the bilateral lower lobe of the lungs. Renal biopsies showed crescentic glomerulonephritis, and MPA was diagnosed based on these criteria. The patient exhibited dramatic clinical and imaging improvements after immunosuppressive treatment.
UNASSIGNED: The organs most commonly involved in MPA in children are the lungs, kidneys, skin, nervous system organs, and organs of the gastrointestinal tract. Careful examination should be carried out in these patients while biopsies of the kidney or any other organs remain the gold standard for diagnostic purposes. Pulmonary involvement may be the initial symptom of the disease and should not be confused with pneumonia. A urinalysis should be performed in patients with hemoptysis. Antibiotics should be used with caution.