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.

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.

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.

A Transient Increase in the Serum ANCAs in Patients with SARS-CoV-2 Infection: A Signal of Subclinical Vasculitis or an Epiphenomenon with No Clinical Manifestations? A Pilot Study.

A relationship is emerging between SARS-CoV-2 infections and ANCA-associated vasculitis (AAV) because: (i) the pulmonary involvement of COVID-19 may mimic that observed in patients with AAV; (ii) the two diseases may occur together; (iii) COVID-19 may trigger AAV. However, few cases of AAV have been identified so far in COVID-19 patients. To define the frequency of ANCA autoimmunity in patients with SARS-CoV-2 infection, we analyzed the serum ANCAs and the serum PR3 and MPO antigens by immunoassays in 124 adult patients with a diagnosis of SARS-CoV-2 infection (16 were asymptomatic and 108 were hospitalized) and 48 control subjects. The serum ANCAs were significantly higher in the hospitalized patients compared with either the controls or the asymptomatic patients and increased with the progression of the COVID-19 severity. After one week of hospitalization, the values were significantly lower. In contrast, no differences emerged among the controls, asymptomatic and hospitalized patients for the PR3 and MPO serum levels. None of the patients had clinical signs of AAV with the exception of a severe pulmonary involvement. Further studies are necessary to define whether the increase in the serum ANCAs might mask subclinical vasculitis in a percentage of patients with SARS-CoV-2 infection or it is an epiphenomenon of SARS-CoV-2 infection with no clinical manifestations.

Acute ANCA Vasculitis and Asymptomatic COVID-19.

We describe the presentation and diagnosis of a child with newly diagnosed antineutrophil cytoplasmic antibody-associated vasculitis and associated diffuse alveolar hemorrhage who was positive for coronavirus disease 2019 immunoglobulin G antibodies, indicative of a previous asymptomatic infection. Results of multiple polymerase chain reaction tests coinciding with the start of symptoms were negative, indicating that acute infection was not the cause of the patient's symptoms. Coronavirus disease 2019-induced autoimmune diseases have been described in adults, but this case report represents the first case described in a pediatric patient.