A Fatal Case of Rapidly Progressive Glomerulonephritis With Two Anti-neutrophil Cytoplasmic Antibodies and Anti-glomerular Basement Membrane Antibody: A Description of Autopsy Findings

A 79-year-old man presented with dyspnea upon exertion, marked renal dysfunction, proteinuria, and hematuria. He was diagnosed with rapidly progressive glomerulonephritis. Serological tests were positive for MPO-ANCA, PR3-ANCA, and anti-GBM antibodies. Since the anti-GBM antibody titer was significantly higher than the ANCA titer and the renal dysfunction was severe, we initially assumed anti-GBM disease and started treatment. Due to poor general condition, a definitive diagnosis could not be made by renal biopsy. Corticosteroid therapy, plasmapheresis, and cyclophosphamide treatment were performed. However, renal function did not improve, and hemodialysis was required. He died of sepsis during treatment. An autopsy was performed with the consent of the family. Renal pathological examination revealed fibrocellular crescent formation in the glomeruli. Immunofluorescence revealed no major deposition in the glomeruli, suggesting ANCA-associated nephritis but not anti-GBM disease. Gross pathological findings of the abdominal aorta showed that a part of the artificial blood vessel had formed a pseudoaneurysm and abscess. There is no evidence of inflammatory cell infiltration or vasculitis in the alveoli. Pathological findings in the other organs did not suggest vasculitis. The renal prognosis of this case could have been improved with appropriate treatment if early diagnosis by renal biopsy had been made. There have been case reports of triple-seropositive rapid progressive glomerulonephritis (RPGN). We report a rare autopsy case of triple-seropositive RPGN.