Rapidly progressive glomerulonephritis and Wegener's granulomatosis.

Wegener's granulomatosis is estimated at 1/100.000/year. Histological proof of the characteristic granuloma is only demonstrated in 1/3 of patients suspected of having WG. The ANCA test is essential in making the diagnosis. Wegener's granulomatosis can affect any organ system. That the beginning of the disease is restricted to one organ (limited WG) is postulated to be true in at least 1/3 of all patients. One peculiar organ manifestation of WG is the pulmonary-renal syndrome. Renal involvement in WG is common and can reach from pauci-immune mild mesangial to crescentic lesions, depending on the severity of the disease. Predictors of renal outcome are glomerular obsolescence and degree of tubulo-interstitial lesions.