The exact cause of Wegener's Disease (GPA) is currently unknown. It is believed to be an auto-immune disease, where the body mistakenly attacks it's own tissues. In a similar way to other auto-immune diseases it is thought that there is a genetic component to Wegener's. Sufferers are likely to have a gene or genes which makes them more likely to contract the disease. The immune system is influenced by many thousands of genes, and it may be the case that there has to be a variation in several different genes in combination which results in that person being more susceptible to Wegener's. Men are more likely to contract GPA than women and the disease is most common in those in their forties, fifties and sixties. Caucasians are at more risk than any other ethnicities.
But it isn't all down to genetics. Wegener's Granulomatosis is very unusual to occur more than once in the same family. This means that you are unlikely to pass Wegener's on to your children.
It's is believed that the GPA is triggered by an external factor such as an infection with a virus, fungus or bacteria. When the immune system kicks into action abnormally against a particular infection, chemical or toxin the Wegener's Disease begins.
Some research suggests that Wegener's Disease may be triggered by exposure to silica or to infection with staphylococcus aureus bacteria, though this has yet to be proven. As the upper airways are invariably affected, the suspicion is that the allergen is inhaled.
Wegener's Disease is definitely not a form of cancer.
As the cause of Wegener's Disease is unknown, there is no known way to prevent the disease.
Image used under Creative Commons Licence by Nathan Reading.