Anti-neutrophil cytoplasmic antibody-associated vasculitis associated with infectious mononucleosis due to primary Epstein-Barr virus infection: report of three cases

Upper Respiratory Microbiome in Vasculitis

The pathogenesis of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), such as granulomatosis with polyangiitis, is not well understood. These diseases cause significant inflammation in the upper airway. The nares and upper airway are host to many commensal microbes as well as a frequent site of exposure to pathogenic microbes. This review explores the association between upper airway microbial dysregulation and AAV. The role of Staphylococcus aureus colonization as a possible driver of disease is discussed, as well as recent work exploring how fluctuations in the abundance and diversity of commensal microbes are related to vasculitis and risk of flare.

Deciphering the association between biopsy-confirmed systemic small vessel vasculitis and Epstein-Barr virus-positive polymorphic B-cell lymphoproliferation

The Epstein-Barr virus (EBV) is associated with various lymphoproliferative disorders (LPDs). Additionally, EBV infection has correlated with diverse autoimmune diseases. However, the association between EBV and systemic small vessel vasculitis (SVV) remains controversial. Here, we report a case of SVV with pauci-immune glomerulonephritis accompanied by an EBV-positive polymorphic B-cell LPD, not otherwise specified. The intricate distinction between EBV-positive B-cell LPD and SVV was difficult, as both diseases demonstrated similar clinical presentations. Lymph node and kidney biopsies facilitated the accurate diagnosis of these two conditions. The administration of high-dose prednisolone, combined with rituximab, proved efficacious, with no instances of relapse over the subsequent 2-year period. This case indicates an association between EBV-positive B-cell LPD and SVV. The diligent execution of biopsies is a crucial diagnostic and interpretive strategy, generating precise comprehension of this condition and guiding its appropriate therapeutic management.

Genetic and Non-Genetic Contributions to Eosinophilic Granulomatosis with Polyangiitis: Current Knowledge and Future Perspectives

In this work, we present a comprehensive overview of the genetic and non-genetic complexity of eosinophilic granulomatosis with polyangiitis (EGPA). EGPA is a rare complex systemic disease that occurs in people presenting with severe asthma and high eosinophilia. After briefly introducing EGPA and its relationship with the anti-neutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAVs), we delve into the complexity of this disease. At first, the two main biological actors, ANCA and eosinophils, are presented. Biological and clinical phenotypes related to ANCA positivity or negativity are explained, as well as the role of eosinophils and their pathological subtypes, pointing out their intricate relations with EGPA. Then, the genetics of EGPA are described, providing an overview of the research effort to unravel them. Candidate gene studies have investigated biologically relevant candidate genes; the more recent genome-wide association studies and meta-analyses, able to analyze the whole genome, have confirmed previous associations and discovered novel risk loci; in the end, family-based studies have dissected the contribution of rare variants and the heritability of EGPA. Then, we briefly present the environmental contribution to EGPA, reporting seasonal events and pollutants as triggering factors. In the end, the latest omic research is discussed and the most recent epigenomic, transcriptomic and microbiome studies are presented, highlighting the current challenges, open questions and suggesting approaches to unraveling this complex disease.

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.

Epstein-Barr virus reactivation induced myeloperoxidase-specific antineutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitis

We present a patient with systemic symptoms including 4 months of dyspnoea worsened with exertion, fatigue, rhinorrhoea, intermittent facial swelling, generalised lymphadenopathy and weight loss. Laboratory studies demonstrated proteinuria and eosinophilia. His serology was consistent with Epstein-Barr Virus (EBV) reactivation. A lymph node biopsy was consistent with EBV-associated reactive lymphoid hyperplasia. He was told to continue symptomatic treatment for EBV infection. After several admissions, vasculitis workup and myeloperoxidase-antineutrophil cytoplasmic autoantibody (ANCA) studies were positive. Evolution of clinical symptoms, laboratory parameters and our literature review suggested the diagnosis of EBV-associated ANCA vasculitis. Steroids were started after the patient continued to deteriorate; the viral load started increasing, so we added valganciclovir with favourable clinical response and no relapse during the follow-up for 6 months. This suggests that with evidence of viraemia (primary or reactivation), antiviral treatment likely has clinical benefit while immunosuppression is being considered.

Fatal Systemic Vasculitis Associated with Chronic Active Epstein-Barr Virus Infection

Chronic active Epstein-Barr virus infection is a rare disease with an often fatal outcome. Cardiovascular complications are associated with a poor prognosis. We herein describe the clinical course of an adult patient with Epstein-Barr virus-associated systemic vasculitis complicated by multi-systemic aneurysmal disease. The vascular imaging showed multiple aneurysms involving coronary arteries, abdominal arteries, cerebral arteries, and vertebral arteries. Immunophenotyping analysis of peripheral blood lymphocytes revealed the presence of an increased number of double negative T cells. The patient received multiple lines of immunosuppressive therapy with no response. Unfortunately, he succumbed to a cerebral aneurysm rupture.

Infection-induced myeloperoxidase specific antineutrophil cytoplasmic antibody (MPO-ANCA) associated vasculitis: A systematic review

BACKGROUND

We conducted a systematic review to identify cases of infection-induced anti-myeloperoxidase (MPO) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

PubMed/Medline databases were searched from inception to July of 2020, according to PRISMA guidelines.

RESULTS

Among the 618 abstracts identified, 18 articles describing 23 patients (60.9% female, mean age 50.5 years) were included. Median time between infection and vasculitis development was 3 months. Five (21.7%) patients expired during follow-up. Vasculitis regressed after the resolution of infection in 12/23 (52.2%). ANCA titers decreased significantly on follow-up in 14/16 patients and in all survivors in which they were measured. Pathogens reported included Mycobacterium spp., Coccidioides spp., Rickettsia rickettsii, Staphylococcus spp., EBV, CMV and Dengue virus.

CONCLUSIONS

MPO-AAV can occur after infection and may regress after its resolution. Infection should be considered in cases of MPO-AAV, as immunosuppressive treatment can have catastrophic results if the infection is not adequately treated.

Neutrophils in viral infection

Neutrophils are the first wave of recruited immune cells to sites of injury or infection and are crucial players in controlling bacterial and fungal infections. Although the role of neutrophils during bacterial or fungal infections is well understood, their impact on antiviral immunity is much less studied. Furthermore, neutrophil function in tumor pathogenesis and cancer treatment has recently received much attention, particularly within the context of oncolytic virus infection where neutrophils produce antitumor cytokines and enhance oncolysis. In this review, multiple functions of neutrophils in viral infections and immunity are discussed. Understanding the role of neutrophils during viral infection may provide insight into the pathogenesis of virus infections and the outcome of virus-based therapies.

Epstein-Barr virus-related cutaneous necrotizing vasculitis in a girl heterozygous for factor V Leiden

BACKGROUND

Necrotizing vasculitides are basically characterized by vessel wall neutrophil infiltration and necrosis and they can occur as a primary process or secondary to an underlying disease. Although Henoch-Schönlein purpura (HSp) is the more frequent primary vasculitis in childhood, sometimes it has to be distinguished from other secondary vasculitides induced by infections, drugs, vaccines, or immune-mediated disorders.

MAIN OBSERVATIONS

We report a case of a 14-year-old girl with cutaneous necrotizing vasculitis, appearing in the course of acute Epstein-Barr virus infection. Physical examination revealed highly aching erythematous-purple lesions with reticular edges localized on the back of feet. Pain was non-responsive to ibuprofen and required administration of tapentadol and pregabalin. The patient was also heterozygous for factor V Leiden that might have contributed to the development of cutaneous painful lesions.

CONCLUSIONS

To our knowledge this is the first documented pediatric case of necrotizing vasculitis associated with acute EBV infection in a girl heterozygous for factor V Leiden. In this patient the severity of skin manifestations might have been influenced by the concomitant factor V Leiden, which gave rise to hypercoagulability and occlusive vasculopathy with markedly severe pain, a symptom rather infrequent in other childhood vasculitides.

Henoch-Schonlein purpura associated with primary active Epstein-Barr virus infection: a case report

Henoch-Schönlein purpura (HSP) is the most common form of childhood vasculitis. Various viral and bacterial infections, drugs, vaccines, food allergy and even insect bites have been considered as triggering factors in pathogenesis of HSP. Epstein-Barr virus (EBV) infection, which is associated with HSP, have been rarely reported. Herein we present HSP patient possibly caused by EBV infection. A 8-year old boy was admitted to our department with fever, rashes on legs and arms and intermittent mild abdominal pain. Multiple purpuric rashes were on his extremities, abdomen and buttock. Laboratory investigations revealed that monospot test was positive, EBV serology tests; Anti-EA-D Ig G: 3+, Anti-VCA gp125 Ig G: 3+, Anti-VCA p19 Ig M: 2+, Anti EBNA-1 Ig M: negative, Anti EBNA-1 Ig M: negative, Anti EBNA-1 Ig G: negative. The patient was interpreted as the primary active acute EBV infection. A skin biopsy showed leucocytoclastic vasculitis. The other viral and bacterial investigations were negative. The patient was diagnosed as HSP vasculitis according to EULAR criteria and treated with intravenous hydration and ibuprofen. He was discharged after 15 days with normal laboratory findings and physical examination. We think that EBV infection may be stimulant factor for autoimmune reactions and may cause HSP vasculitis. Hence, it may be useful to investigate the EBV infection in etiology of HSP cases.