Wegener granulomatosis is a rare (incidence 3 per 100,000) granulomatous vasculitis involving predominantly the upper airways, lower airways and kidneys. Other organs such as the heart, the peripheral nerves and the joints can also be involved. Typically, patients present with nasal congestion and bleeding, with or with out changes in hearing. They often feel tired, lose weight and have have joint and muscle aches. The initial evaluation by the physician will often reveal asymptomatic lesions on the chest x-ray and urinary abnormalities. The c-ANCA test is often positive. Microscopic polyarteritis is similar to WG, although the nature of the inflammation in the lung is different. WG demonstrates granulomatous vasculitis of small veins and arteries, while MPA demonstrates non-granulomatous capillaritis. Patients with MPA are more likely to have respiratory hemorrhage than patients with WG.
Both WG and MPA are presumably due to some inhaled infection or other antigen. They can be rapidly fatal if untreated, but have a very good prognosis if treated appropriately with steroids and cyclophosphamide. Some patients will have episodes of relapse after the intial course of treatment. Long term complications may result from recurrent infections of tissues in the upper airways that have been damaged during the active phase of WG or MPA.
SADRC-WNY has been trying to understand how inflammatory reactions that start in the airways end up in the kidneys, in the absence of immune compexes.
Wegener granulomatosis links page: www.weareb.org/WG/wglinks.html
Wegener granulomatosis support group: wgsg.org/
Microscopic polyarteritis links page: www.blackandwhite.org/micro/index.shtml