Wegener granulomatosis (WG) is a systemic disease that is often associated with an immune-mediated form of glomerulonephritis (GN). Renal disease most often manifests as microscopic hematuria with or without red blood cell or mixed cellular casts, proteinuria, and an elevated serum creatinine concentration.We conducted the current study to determine whether persistent hematuria, in the setting of apparent clinical remission, may reflect glomerular injury and not active renal disease. We performed a retrospective analysis of data from 82 patients with new-onset WG, of whom 25 had GN at presentation.Twenty of 25 patients with GN achieved sustained remissions (>6 consecutive months' duration). During initial periods of active disease the median peak serum creatinine was 1.9 mg/dL (range, 0.6-13.6 mg/dL). The median time to remission was 4 months (range, 2-13 mo). After effective therapy, median creatinine was 1.1 mg/dL (range, 0.4-1.8 mg/dL). Ten of 20 patients had prolonged hematuria over a period of >6 months. Within this subset, 5 subsequently normalized urine over a median period of 11 months and 5 did not achieve normal urine sediment over a median follow-up of 38 months. Thus, 10 of 25 patients with WG and GN had sustained hematuria in spite of apparent prolonged clinical remission.Patients with WG and GN may achieve enduring remissions that allow withdrawal of medications in spite of continued microscopic hematuria with or without red blood cell casts that may persist for months or even years. Continued use of aggressive immunosuppressive therapies in such patients would be ill-advised and could lead to irreversible and even life-threatening side effects from cyclophosphamide or high-dose corticosteroids.