Increase in the number of new cases of ANCA-associated vasculitis in the COVID-19 vaccine era.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is an autoimmune vasculitis characterized by the production of antibodies against ANCA, with unclear pathogenesis. With the ongoing COVID-19 pandemic, COVID-19 mRNA vaccination has been available in Japan since February 2021. Although autoimmune symptoms have been reported after COVID-19 vaccinations, there have been no clinical investigations regarding the relationship between COVID-19 mRNA vaccines and the pathogenesis of AAV. Thus, the present study aimed to investigate whether the administration of COVID-19 mRNA vaccines affects the development of AAV. The study identified patients with new-onset AAV who were MPO-ANCA or PR3-ANCA positive and met the entry criteria of the AAV EMA classification algorithm. The study compared the number of new AAV cases per year before and after the start of the COVID-19 mRNA vaccine program in Japan. The study found that the annual number of new cases of AAV in Japan's Nagasaki Prefecture increased by approximately 1.5-fold since the COVID-19 vaccine program was initiated, suggesting a possible link between the COVID-19 mRNA vaccines and the development of AAV. Although the study provides insight into the clinical evaluation and management of autoimmune symptoms following COVID-19 vaccination, further investigation of the possible association between COVID-19 mRNA vaccines and the pathogenesis of AAV is required.

Cellular and humoral responses after second and third SARS-CoV-2 vaccinations in patients with autoimmune diseases treated with rituximab: specific T cell immunity remains longer and plays a protective role against SARS-CoV-2 reinfections.

Background: Humoral and cellular immune responses are known to be crucial for patients to recover from COVID-19 and to protect them against SARS-CoV-2 reinfection once infected or vaccinated. Objectives: This study aimed to investigate humoral and T cell responses to SARS-CoV-2 vaccination in patients with autoimmune diseases after the second and third vaccine doses while on rituximab and their potential protective role against reinfection. Methods: Ten COVID-19-naïve patients were included. Three time points were used for monitoring cellular and humoral responses: pre-vaccine to exclude virus exposure (time point 1) and post-second and post-third vaccine (time points 2 and 3). Specific IgG antibodies were monitored by Luminex and T cells against SARS-CoV-2 spike-protein by ELISpot and CoVITEST. All episodes of symptomatic COVID-19 were recorded. Results: Nine patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis and one with an undifferentiated autoimmune disease were included. Nine patients received mRNA vaccines. The last rituximab infusion was administered for a mean (SD) of 15 (10) weeks before the first vaccine and six patients were CD19-B cell-depleted. After a mean (SD) of 19 (10) and 16 (2) days from the second and third vaccine dose, IgG anti-SARS-CoV-2 antibodies were detected in six (60%) and eight (80%) patients, respectively. All patients developed specific T cell responses by ELISpot and CoVITEST in time points 2 and 3. Previous B cell depletion correlated with anti-SARS-CoV-2 IgG levels. Nine (90%) patients developed mild COVID-19 after a median of 7 months of the third dose. Conclusion: Rituximab in patients with autoimmune diseases reduces humoral responses but does not avoid the development of T cell responses to SARS-CoV-2 vaccination, which remain present after a booster dose. A steady cellular immunity appears to be protective against subsequent reinfections.

Patient reported outcomes in systemic vasculitis.

PURPOSE OF REVIEW: This review paper evaluates the use of patient reported outcome (PROs) in systemic vasculitis and the increasing incorporation of these measures in the evaluation of clinical outcomes and healthcare provision. RECENT FINDINGS: Generic PROs such as the SF-12, SF-36, EQ-5D have been used to evaluate health-related quality of life (HRQOL) across the spectrum of vasculitis; including giant cell arteritis, antineutrophil cytoplasmic antibody (ANCA)-related vasculitis and immunoglobulin A vasculitis (IgA) vasculitis. More recently disease-specific PROs have been developed including the associated vasculitis (AAV)-PRO and GCA-PRO, whilst further work is ongoing including a Steroid-PRO. SUMMARY: Generic and disease-specific PROs are complimentary in nature, but the advent of disease-specific PROs allows evaluation of the impact of specific symptoms and intervention on patient HRQOL. Following the COVID-19 pandemic, the advent of increasing virtual work has brought the potential for electronic-PRO measures to the forefront and is a current area of interest.

The HAVEN study-hydroxychloroquine in ANCA vasculitis evaluation-a multicentre, randomised, double-blind, placebo-controlled trial: study protocol and statistical analysis plan.

BACKGROUND: Patients with non-severe ANCA-associated vasculitis (AAV) are often prescribed immunosuppressive medications that are associated with severe side effects and a reduced quality of life. There is an unmet need for safer effective treatments for these patients. Hydroxychloroquine is being explored due to its effect in similar autoimmune conditions such as systemic lupus erythematosus. METHODS: Double-blind, placebo-controlled multicentre trial recruiting 76 patients across 20 sites. Participants will be randomised 1:1 to hydroxychloroquine or placebo in addition to standard of care immunosuppressive therapies over the course of 52 weeks. A phase II selection design will be used to determine hdroxychloroquine's efficacy, using prednisolone dosage and Birmingham Vasculitis Activity Score as a measure of disease activity. Secondary outcomes will explore other elements of AAV progression, including disease flares and time to remission. DISCUSSION: This trial aims to explore Hydroxychloroquine as a treatment for patients with AAV. If effective, the need for immunosuppressive treatments such as prednisolone could be reduced. Hydroxychloroquine is safer, cheaper and has fewer adverse effects than conventional immunosuppressive treatments. This could improve patient outcomes while saving money for the NHS. TRIAL REGISTRATION: ISRCTN: ISRCTN79334891. Registered 07 June 2021. EudraCT: 2018-001268-40. Registered 13 September 2019. CLINICALTRIALS: gov: NCT04316494. Registered 20 March 2020.

Glomerulonephritis associated with systemic sclerosis: a case report.

BACKGROUND: Systemic sclerosis is a multiorgan autoimmune disease that can overlap with other rheumatologic disorders; however, co-occurrence with antineutrophil cytoplasmic antibody-associated vasculitis is rare. CASE PRESENTATION: A 39-year-old Persian female patient with systemic sclerosis according to American College of Rheumatology/European League Against Rheumatism 2013 criteria with a disease duration of 6 years was admitted to the hospital due to a rise in creatinine level in July 2021. She had complaints of nasal speech and feeling of nasal perforation. The first symptoms of antineutrophil cytoplasmic antibody-associated vasculitis had started 5 years earlier with palpable purpura in the lower limbs, hemoptysis, and positive perinuclear (p)-antibody-associated vasculitis level (> 300 AU/mL). Still, the diagnosis was not achieved due to the patient's reluctance to undergo a biopsy. She was treated with azathioprine (150 mg/day) and prednisolone (10 mg/day) during the 5-year follow-up. Her renal biopsy results showed cortical renal tissue with a cellular crescent in more than 50% of the specimen, rupture of the Bowman capsule and the glomerular basement membrane, peri-glomerular inflammation, and mild tubular atrophy in microscopic examinations. The immunofluorescence study resulted in a granular pattern of immune deposits along the glomerular basement membrane, mesangial tissue, and tubular basement membranes. CONCLUSION: We reported a rare case of comorbid systemic sclerosis and antineutrophil cytoplasmic antibody-associated vasculitis with nasal perforation. Her renal biopsy showed immune deposits along the glomerular basement membrane, mesangial tissue, and tubular basement membranes. Overlapping with other collagen vascular diseases can occur in rheumatology patients with uncommon manifestations. In systemic sclerosis, renal involvement in the form of glomerulonephritis is infrequent, and comorbid systemic lupus erythematosus or antineutrophil cytoplasmic antibody-associated vasculitis should be considered.

Identification of differentially expressed genes and pathways in kidney of ANCA-associated vasculitis by integrated bioinformatics analysis.

The antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systematic of relatively rare autoimmune diseases with unknown cause. Kidney involvement is one of the most common clinical manifestations, and the degree of renal damage is closely associated with the development and prognosis of AAV. In this study, we utilized the Robust Rank Aggreg (RRA) method in R to integrate GSE104948, GSE104954, GSE108109, GSE108112, and GSE108113 profile datasets loaded from Gene Expression Omnibus (GEO) database and identified a set of differentially expressed genes (DEGs) in kidney between AAV patients and living donors. Then, the results of gene ontology (GO) functional annotation showed that immunity and metabolism involved process of AAV both in glomerulus and tubulointerstitial. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that following pathways, such as complement and coagulation cascades pathway; Staphylococcus aureus infection; disease-COVID-19; and systemic lupus erythematosus (SLE) pathway play a crucial role in AAV. Next, the results analyzed by protein-protein interaction (PPI) network and Cytoscape software exhibited the hub genes ALB, TYROBP, and CYBB existed in both glomerular and tubulointerstitial compartments datasets. Finally, KEGG analysis using genes of two most important modules also further validated complement and coagulation cascades pathway and S. aureus infection existed both in glomerulus and tubulointerstitial compartments datasets. In conclusion, this study identified key genes and pathways involved in kidney of AAV, which was benefit to further uncover the mechanisms underlying the development and progress of AAV, biomarkers, and potential therapeutic targets as well.

Successful Treatment of Post-COVID-19 Severe ANCA-Associated Vasculitis: Case Report (preprint)

Background The SARS-CoV-2 pandemic has become the most serious health problem of today globally. Kidney involvement in patients with coronavirus disease 2019 (COVID-19) is common and associated with high mortality. Although acute tubular necrosis due to hemodynamic instability is the most common cause, other complex and destructive processes related to cytokine storm and activation of innate and adaptive immunity have also been reported.Case presentation: Herein, we present successful treatment of proteinase-3 anti-neutrophil cytoplasmic antibodies (PR3-ANCA)-associated vasculitis case presenting with severe pulmonary-renal syndrome as a rare and fatal complication of COVID-19 infection.Conclusions AAV is a serious disease and prompt treatment is one of the most important factors in patient survival.

Hepatic and pulmonary involvement in a patient with PR3-ANCA vasculitis following SARS-CoV-2 vaccination: A case report.

We here report the first case of anti-proteinase 3-positive anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis following the severe acute respiratory syndrome coronavirus 2 Pfizer-BioNTech vaccine presenting with prominent liver involvement and alveolar haemorrhage. Two weeks after vaccination, a 49-year-old man developed inflammatory arthralgias and hypertransaminasaemia. Two months later, fever and haemoptysis appeared; the patient tested positive for anti-proteinase 3 autoantibodies. High-dose steroids and rituximab were started, and complete remission was achieved. Systemic autoimmune diseases, including ANCA-associated vasculitis, should always be considered in the differential diagnosis of hypertransaminasaemia, especially when the clinical context is suspicious.

Development of ANCA-associated vasculitis followed by SARS-CoV-2 vaccination in a patient with HLA-DRB1*09:01 allele.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), presents with severe pneumonia and fatal systemic complications. Currently, SARS-CoV-2 vaccines are effective in reducing the risk of new onset and getting worse of the disease. However, autoimmune diseases such as antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) have been reported to develop after COVID-19 vaccine administration. A 71-year-old woman presented with fever, malaise, urinary abnormalities, and renal dysfunction after receiving the COVID-19 vaccine (Pfizer-BioNTech). We clinically diagnosed AAV with her manifestations and serological test (myeloperoxidase-ANCA-positive). Her clinical findings were improved after immunosuppressive therapy. We examined her genetic susceptibility to AAV, and we found that her allele was HLA-DRB1*09:01, which is a risk allele of myeloperoxidase-AAV. Mechanistically, SARS-CoV-2 vaccines would activate immunity, including neutrophils, and trigger AAV onset in this patient with a genetic risk to develop AAV. The pathophysiology of this case would share with that of autoimmune/inflammatory syndrome induced by adjuvants in the absence of external adjuvants.

Targeting Cathepsin C in PR3-ANCA Vasculitis.

BACKGROUND: The ANCA autoantigens proteinase 3 (PR3) and myeloperoxidase (MPO) are exclusively expressed by neutrophils and monocytes. ANCA-mediated activation of these cells is the key driver of the vascular injury process in ANCA-associated vasculitis (AAV), and neutrophil serine proteases (NSPs) are disease mediators. Cathepsin C (CatC) from zymogens activates the proteolytic function of NSPs, including PR3. Lack of NSP zymogen activation results in neutrophils with strongly reduced NSP proteins. METHODS: To explore AAV-relevant consequences of blocking NSP zymogen activation by CatC, we used myeloid cells from patients with Papillon-Lefèvre syndrome, a genetic deficiency of CatC, to assess NSPs and NSP-mediated endothelial cell injury. We also examined pharmacologic CatC inhibition in neutrophil-differentiated human hematopoietic stem cells, primary human umbilical vein cells, and primary glomerular microvascular endothelial cells. RESULTS: Patients with Papillon-Lefèvre syndrome showed strongly reduced NSPs in neutrophils and monocytes. Neutrophils from these patients produced a negative PR3-ANCA test, presented less PR3 on the surface of viable and apoptotic cells, and caused significantly less damage in human umbilical vein cells. These findings were recapitulated in human stem cells, in which a highly specific CatC inhibitor, but not prednisolone, reduced NSPs without affecting neutrophil differentiation, reduced membrane PR3, and diminished neutrophil activation upon PR3-ANCA but not MPO-ANCA stimulation. Compared with healthy controls, neutrophils from patients with Papillon-Lefèvre syndrome transferred less proteolytically active NSPs to glomerular microvascular endothelial cells, the cell type targeted in ANCA-induced necrotizing crescentic glomerulonephritis. Finally, both genetic CatC deficiency and pharmacologic inhibition, but not prednisolone, reduced neutrophil-induced glomerular microvascular endothelial cell damage. CONCLUSIONS: These findings may offer encouragement for clinical studies of adjunctive CatC inhibitor in patients with PR3-AAV.

Anti-SARS-CoV-2 inactivated vaccine in patients with ANCA-associated vasculitis: Immunogenicity, safety, antibody decay and the booster dose.

OBJECTIVE: To evaluate inactivated CoronaVac prime vaccination, antibody decay, booster dose, and safety in ANCA-Associated Vasculitis (AAV) patients. METHODS: Fifty-three AAV patients and 106 Controls (CG) received CoronaVac on days: D0 (first dose), D28(second dose), and D210 (booster dose, 32 AAV: 32 CG). The primary outcome was immunogenicity after the second vaccine dose (day 69) assessed by Seroconversion Rates (SC) of anti-SARS-CoV-2 S1/S2 IgG and Neutralizing Antibodies (NAb). Secondary outcomes were safety, immunogenicity (D28/D240), 6-months antibody decay (D210) and the booster dose response (D240). RESULTS: At D69 SC (65.1% vs. 96.8%, p = 0.0001), GMT (21.3 UA/mL vs. 67.7 UA/mL, p < 0.001) and NAb- positivity (53.7% vs. 80.6%, p = 0.001) were moderate but lower in naïve-AAV patients than CG. Patients without SC used more often IS (93.3% vs. 53.3%, p = 0.015), mycophenolate mofetil (20% vs. 0%, p = 0.037) and prednisone (60.0% vs. 28.6%, p = 0.057) than seroconverted. NAb negativity in AAV patients was associated with prednisone treatment (57.9% vs. 18.2%, p = 0.015) and IS (84.2% vs. 55.0%, p = 0.046). Logistic regression analysis models showed that only prednisone was associated with lower seroconversion (OR = 0.2, 0,95% CI 0.05‒0.86, p = 0.030) and with lower NAb positivity (OR = 0.2, 0,95% CI 0.05‒0.88, p = 0.034). After six months (D69‒D210) a decrease in IgG positivity occurred in 32 AAV patients (15.7%, p = 0.074) and 32 CG (18.7%, p = 0.041). For the NAb positivity, the 6-month decrease was not significant (p = 0.114) whereas a major reduction occurred for CG (p < 0.001). A booster dose (D240) resulted in an increment in IgG-positivity (21.9%, p = 0.023) and NAb-positivity (34.4%, p = 0.006) in AAV patients. No moderate/severe adverse events attributable to the vaccine were observed. CONCLUSION: This study provides novel data on the excellent safety and moderate immunogenicity of CoronaVac in AAV patients. A six-month mild antibody waning was observed with a good response to the booster dose, although levels remained lower than CG (CoronavRheum-NCT04754698).

Environmental factors influencing the risk of ANCA-associated vasculitis.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of diseases characterized by inflammation and destruction of small and medium-sized blood vessels. Clinical disease phenotypes include microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic granulomatosis with polyangiitis (EGPA). The incidence of AAV has been on the rise in recent years with advances in ANCA testing. The etiology and pathogenesis of AAV are multifactorial and influenced by both genetic and environmental factors, as well as innate and adaptive immune system responses. Multiple case reports have shown that sustained exposure to silica in an occupational environment resulted in a significantly increased risk of ANCA positivity. A meta-analysis involving six case-control studies showed that silica exposure was positively associated with AAV incidence. Additionally, exposure to air pollutants, such as carbon monoxide (CO), is a risk factor for AAV. AAV has seasonal trends. Studies have shown that various environmental factors stimulate the body to activate neutrophils and expose their own antigens, resulting in the release of proteases and neutrophil extracellular traps, which damage vascular endothelial cells. Additionally, the activation of complement replacement pathways may exacerbate vascular inflammation. However, the role of environmental factors in the etiology of AAV remains unclear and has received little attention. In this review, we summarized the recent literature on the study of environmental factors, such as seasons, air pollution, latitude, silica, and microbial infection, in AAV with the aim of exploring the relationship between environmental factors and AAV and possible mechanisms of action to provide a scientific basis for the prevention and treatment of AAV.

Antineutrophil Cytoplasmic Antibody-associated Vasculitis after COVID-19 Vaccination with Pfizer-BioNTech.

The extent of rare side effects of mRNA vaccines for coronavirus disease 2019 (COVID-19) remains unclear. Several cases of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) following COVID-19 vaccination have been reported. We herein report a 72-year-old man who presented with a fever after receiving the second dose of the Pfizer-BioNTech COVID-19 vaccine. He was diagnosed with acute kidney injury due to myeloperoxidase-ANCA-associated vasculitis and was treated with intermittent hemodialysis, high-dose prednisolone, and intravenous rituximab. His general symptoms and renal impairment subsequently improved. When systemic symptoms are prolonged or renal abnormalities appear after COVID-19 vaccination, the possibility of AAV should be considered.

A case of ANCA-associated vasculitis in a 16-year-old female following SARS-COV-2 infection and a systematic review of the literature.

BACKGROUND: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare form of vasculitis in children. SARS-CoV-2, the virus that causes COVID-19 infection, seems to trigger autoimmunity and new-onset autoimmune disease in pediatric and adult patients. We present a case of new-onset AAV following COVID-19 infection in an adolescent patient, and we review the literature of AAV following COVID-19 infection. CASE PRESENTATION: An adolescent female with a history of asthma was diagnosed with mild COVID-19 infection and subsequently developed persistent cough, wheezing, hearing loss, arthralgias, and rash. Her imaging and laboratory workup showed pulmonary nodules and cavitary lesions, elevated inflammatory markers, negative infectious testing, and positive ANCA. She was treated with glucocorticoids, rituximab, and mycophenolate mofetil. At six-month follow-up, she had improvement in her symptoms, pulmonary function tests, imaging findings, and laboratory markers. CONCLUSIONS: We report the second case of new-onset anti-PR3, C-ANCA vasculitis and the fourth case of pediatric-onset AAV following COVID-19 infection. A systematic review of the literature found 6 cases of new-onset AAV in adults after COVID-19 infection. Pediatric and adult patients who develop AAV post COVID-19 infection have few, if any, comorbidities, and show marked radiographic and symptomatic improvement after treatment. There is increasing evidence for COVID-19-induced autoimmunity in children and our case highlights the importance of considering AAV in a child following a recent COVID-19 infection because timely treatment may improve clinical outcomes.

Managing ANCA-associated vasculitis during COVID-19 pandemic: a single-center cross-sectional study.

The objective of the study is to report the outcomes of COVID-19 in ANCA-associated vasculitis (AAV) patients. This was a registry-based observational study conducted at a tertiary care center in north India. AAV patients with at least one follow-up visit between March 2020 and September 2021 were included. Demographic features, clinical manifestations, disease activity, and treatment details of underlying AAV were noted in all patients. Details of COVID-19 infection including severity, treatment, and outcomes were noted. Predictors of COVID-19 severity were determined using univariate analysis. A total of 33 (18.3%) out of 180 AAV patients contracted COVID-19 infection. Moderate COVID-19 infection was seen in 33.3% and severe or critical infection was seen in 36.3% of patients. Seventeen patients (51.5%) required supplemental oxygen therapy. Nine patients had active disease at the time of COVID-19 infection and three of them died due to COVID-19 infection. The risk of COVID-19 infection and its severity did not differ between patients receiving different immunosuppressants including rituximab induction. Hypothyroidism (p = 0.046) and ocular (p = 0.038) involvement due to AAV predicted the development of moderate to severe/critical COVID-19. Three (9.1%) patients died from COVID-19 and the rate of AAV flare after COVID-19 was similar to that in non-COVID-19 patients (15.3/100 person-year vs. 15.6/100 person-year, p = 0.95). Majority of the patients with AAV had moderate to severe or critical COVID-19 infection. The rate of death due to COVID-19 in AAV is higher than in general population. Use of standard remission induction regimens did not lead to increased risk of COVID-19 infection in our AAV cohort.

A Case Report of MPO-ANCA-Associated Vasculitis Following Heterologous mRNA1273 COVID-19 Booster Vaccination.

Despite that clinical trials have been examining the safety profile of coronavirus disease 2019 (COVID-19) vaccines, there are concerns about long-term side effects as the number of vaccinations increases. Herein, we report a case of new-onset renal-limited anti-myeloperoxidase (MPO) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis after booster vaccination with the mRNA 1273 (Moderna) vaccine. A 72-year-old woman with no specific past history, and who had a normal renal function, developed ANCA-associated vasculitis following heterologous booster with mRNA1273 (Moderna) vaccine. After a kidney biopsy, she was diagnosed with ANCA-associated pauci-immune crescentic glomerulonephritis. Her renal function and constitutional symptoms have been improved with treatment with plasmapheresis, intravenous cyclophosphamide and steroid pulse therapy (intravenous 500 mg of methylprednisolone sodium succinate for 3 days) followed by a reduced steroid regimen.

Expert Perspective: Management of Antineutrophil Cytoplasmic Antibody-Associated Vasculitis.

The antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) comprise a major subset of diseases that cause destructive inflammation of small and medium-sized blood vessels. Although these conditions have a predilection for pulmonary and renal involvement, they are in fact protean diseases that can involve essentially any organ system. AAV is among the most difficult rheumatic diseases to diagnose and treat. Therapy for AAV has evolved over the past two decades. Rituximab, an anti-CD20 monoclonal antibody, is now the preferred agent for remission induction in conjunction with a reduced-dose glucocorticoid taper. Rituximab is also often a key therapy for remission maintenance. Glucocorticoid toxicity reduction has become a major priority for treatment regimens. Avacopan, an important new adjunct to remission induction therapy, may reduce glucocorticoid use and its resulting toxicity. The role of avacopan as a remission maintenance agent requires further study. The duration of immunosuppression following remission is guided by a number of factors, including the patient's overall clinical state, the degree of damage from previous disease activity, the tolerability of remission maintenance medications, and SARS-CoV-2 vaccination and immunity status. Certain features, including history of previous relapse, the presence of ANCA directed against proteinase 3, and a diagnosis of granulomatosis with polyangiitis, favor prolonged remission maintenance therapy. The interval between rituximab doses can usually be lengthened over time during the maintenance phase.

COVID-19 associated pediatric vasculitis: A systematic review and detailed analysis of the pathogenesis.

OBJECTIVES: Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2, has opened a new era in the practice of pediatric rheumatology since it has been associated with inflammatory complications such as vasculitis and arthritis. In this review, we aimed to present a detailed analysis of COVID-19 associated pediatric vasculitis. METHODS: A systematic review of the English literature was performed through Pubmed/MEDLINE and Scopus up to January 1st, 2022. Articles including data about the patients with 1) onset of vasculitis <18 years of age, 2) evidence of SARS-CoV-2 exposure, 3) evidence of vasculitis diagnosis (imaging, histopathologic evidences or fulfilling the specific diagnostic/classification criteria) were included in the final analysis. Patients with Kawasaki disease-like vasculitis associated with multisystem inflammatory syndrome in children (MIS-C) were excluded. RESULTS: A total of 25 articles describing 36 patients with COVID-19 associated pediatric vasculitis (median age 13 years; M/F: 2.3) were included. The most frequent phenotype was IgA vasculitis (n=9) followed by chilblains (n=7) and ANCA associated vasculitis (AAV) (n=5). Skin (58.3%) and renal (30.5%) involvements were the most common manifestations of vasculitis. The majority of patients received corticosteroids (40%), while rituximab (14.2%) and cyclophosphamide (11.4%) were the most frequently used immunosuppressive drugs. Remission was achieved in 23 of 28 patients. Five patients (4 with central nervous system vasculitis; 1 with AAV) died. CONCLUSION: Although COVID-19 associated pediatric vasculitis is very rare, awareness of this rare entity is important to secure earlier diagnosis and treatment. The clinical features of COVID-19 associated pediatric vasculitis subtypes look similar to those in pediatric vasculitis not associated with COVID-19. Whether COVID-19 is the reason of the vasculitis or only the trigger remains unknown.