Severe glomerulonephritis with late emergence of classic Wegener's granulomatosis. Report of 4 cases and review of the literature.

We have analyzed an unusual group of 19 patients (15 previously reported) with Wegener's granulomatosis, who presented with severe glomerulonephritis and developed diagnostic respiratory lesions only after 4 to 78 months. Necrotizing glomerulonephritis, often with crescents, and rarely with vasculitis, was the predominant renal lesion. Wegener's granulomatosis was unsuspected initially, since systemic manifestations, such as fever, arthralgias, malaise, and even pulmonary hemorrhage, were nonspecific or transient, and because renal biopsy findings resembled those seen in microscopic polyarteritis or idiopathic crescentic nephritis. Despite therapy, usually with corticosteroids, only 4 patients maintained adequate renal function. Most patients were receiving chronic dialysis when respiratory involvement developed. Cavitary nodular pulmonary infiltrates were seen in 12 of the 17 patients with lung involvement, and otorhinological disease occurred in 10 patients. Arthralgias, fever, and cough, with or without hemoptysis, were common. Wegener's granulomatosis was diagnosed by lung biopsy in 15 cases and by nasal biopsy in 4. Specific treatment was required for the respiratory disease and was delayed in many patients, because of lack of awareness that Wegener's granulomatosis may present with primary glomerulonephritis and become active during chronic renal failure or dialysis. Nevertheless, all but 1 patient eventually responded to treatment, although 3 additional patients died of late complications.