[Crescentic and necrotizing glomerulonephritis with C3 deposition].

Case 1: A 38-year-old female with a history of tonsillitis and sinusitis was admitted to our hospital because of lung edema. On admission, her serum creatinine increased to 5.57 mg/dL. Hypocomplementemia was not found. ASO and MPO-ANCA were 24 U/mL and 12 EU, respectively. She underwent emergency hemodialysis. Renal biopsy showed global sclerosis and fibrocellular crescentic formation, and marked angionecrosis was noted by light microscopy. Granular deposition of C3, IgG and IgM was seen along the capillary walls on immunofluorescence study. Glomerular intramembranous deposits were scattered on electron microscopy. She was treated with intravenous methylprednisolone pulse therapy, and following oral prednisolone administration was decreased gradually. No therapeutic effects were observed, and intermittent hemodialysis was continued and became maintenance hemodialysis therapy. Case 2: A 28-year-old female suffering from both pharyngitis and acute renal failure with systemic edema was admitted to our hospital. On admission, her serum creatinine and ASO were 4.31 mg/dL and 239 U/mL, respectively. MPO-ANCA was negative and CH50 was normal. Hemodialysis was initiated on the 6th hospital day. In renal biopsy, most glomeruli showed cellular crescentic formation, and marked angionecrosis was noted by light microscopy. Global sclerosis was not found in this case. Granular deposition of C3 resembling a starry sky pattern was seen along the capillary walls on immunofluorescence study. Electron microscopy revealed scattered glomerular subepithelial deposits. She was treated with intravenous methylprednisolone pulse therapy and then oral prednisolone administration. Because of the gradual improvement in renal function, hemodialysis was terminated after 53 sessions, however, the patient's chronic renal failure has persisted to date. In these two cases, the pathological findings supported the diagnosis of severe acute post-infectious glomerulonephritis with the characteristic crescentic and necrotizing glomerulonephritis with C3 deposition.