Granulomatosis with polyangiitis (Wegener): clinical aspects and treatment.

Granulomatosis with polyangiitis (GPA) is a systemic necrotizing vasculitis, which affects small- and medium-sized blood vessels and is often associated with cytoplasmic ANCA. GPA occurs in patients between 45 and 60 years old of both genders, and is rarely observed in blacks. The prevalence of GPA increases along a south-north gradient in Europe (20 to 150/million). The main clinical characteristics involve the upper and/or lower respiratory tract and kidneys. Ear, nose and throat manifestations with recurrent sinusitis and crusting rhinorrhea are usually severe. Lung nodules are frequently seen, sometimes excavated. Renal involvement is characterized by rapidly progressive necrotizing glomerulonephritis with extracapillary crescents. Limited forms of GPA predominantly affect the upper respiratory tract, whereas generalized forms of GPA include renal manifestations and/or alveolar hemorrhage and/or vital organ involvement with an altered general condition. The combination of immunosuppressant drugs and corticosteroids has converted this typically fatal illness into one in which 80% of patients achieve remission. However, despite considerable therapeutic progress over the last decades, relapses remain frequent (50% at 5 years), and maintenance treatment is now the main therapeutic challenge.