From the Guidelines
Environmental triggers of Anti-Neutrophil Cytoplasmic Antibody (ANCA) vasculitis include exposure to silica, organic solvents, and farming, which have been associated with an increased risk of the disease. According to a recent study published in Nature Reviews Rheumatology 1, the pathogenesis of EGPA, a type of ANCA vasculitis, is driven by genetic and environmental factors. The study highlights that exposure to silica, organic solvents, and farming was associated with an increased risk of EGPA, whereas cigarette smoking was associated with a lower risk.
Some key points to consider when evaluating environmental triggers of ANCA vasculitis include:
- Genetic studies have highlighted associations between HLA-DQ and MPO-ANCA-positive EGPA, whereas ANCA-negative EGPA is mainly associated with genetic variants involved in mucosal responses and eosinophil biology 1
- Several cell types participate in the immunopathogenesis of the disease, including eosinophils, CD4 + T cells, and type 2 innate lymphoid cells 1
- The clinical phenotype of EGPA is quite heterogeneous, and the diagnosis is not always straightforward, with ANCA detectable in ~40% of cases 1
It is essential to note that the evidence is based on a study of EGPA, a specific type of ANCA vasculitis, and may not be generalizable to all forms of ANCA vasculitis. However, identifying and avoiding potential environmental triggers is an important part of disease management, alongside appropriate immunosuppressive therapy. Further research is needed to fully understand the environmental triggers of ANCA vasculitis and to develop effective strategies for prevention and treatment.
From the Research
Environmental Triggers of ANCA Vasculitis
The environmental triggers of Anti-Neutrophil Cytoplasmic Antibody (ANCA) vasculitis include:
- Silica and asbestos exposure, which are thought to belong to the triggering factors of ANCA-associated vasculitis 2, 3, 4
- Other environmental antigens released during natural disasters and through farming 3
- Assorted geoepidemiological triggers, including seasonality and latitude-dependent factors such as UV radiation 3
- Infection, with Staphylococcus aureus being the most convincing microorganism 3
Specific Studies
- A study published in 2005 found that occupational exposure to silicon-containing chemicals was reported by 22.6% of patients with ANCA-associated vasculitis, compared to 0% of control subjects 2
- A systematic mapping review published in 2020 identified various pollutants, including silica and other environmental antigens, as potential triggers for ANCA-associated vasculitis 3
- A study published in 2006 found that long-term silica exposure may be one of the exogenous factors contributing to ANCA production, but silica exposure alone, without typical silicosis, was not associated with ANCA positivity 4