Renal involvement is the hallmark of generalized disease. Urinalysis shows proteinuria, hematuria, and RBC casts. Renal impairment is inevitable without immediate appropriate therapy. Serum complement levels are normal or elevated. The ESR is elevated.
Leukocytosis is present.
Anemia may be profound. Antinuclear antibodies and LE cells are absent. Diagnosis Wegener's granulomatosis is diagnosed by characteristic clinical, serologic, and pathologic findings. Renal biopsy determines the extent of renal involvement. Open pulmonary biopsy of a solid or cavitating lesion sometimes leads to diagnosis.