“Triple-positive” renal limited vasculitis presenting with rapidly progressive glomerulonephritis: A case report

Abstract

Rationale: Coexistence of anti-glomerular basement membrane (anti-GBM) disease with anti-neutrophil cytoplasmic antibody (ANCA) in a case of glomerulonephritis is often identified as a “double-positive” disease. Interestingly, the majority of “double positive” ANCA is myeloperoxidase (MPO)-ANCA and some of the MPO-ANCA positive cases showed intrarenal arteritis, suggesting an ANCA-associated kidney lesion. Proteinase 3-ANCA positive diseases are also rarely reported. Patients positive for all three antibodies, i.e., triple-positive patients, are extremely rare. Patient’s Concern: A 53 year-old female presented with anasarca and oliguria of 2 months’ duration. Diagnosis: Pauci-immune type renal limited crescentic glomerulonephritis positive for MPO-ANCA, proteinase 3-ANCA, and anti-GBM antibody (triple-positive). Interventions: Intravenous high dose cyclophosphamide, oral azathioprine, intravenous methylprednisolone, and plasma exchange as per British Health Professionals in Rheumatology Guidelines. Outcomes: After one-month follow-up, anasarca and proteinuria were lessened, serum creatinine was normalized, titers of MPO-ANCA levels were decreased, and anti-GBM antibody levels were normalized. Lessons: Triple-positive renal limited vasculitis is rare and response to combined immunosuppressive therapy and plasma exchange can contribute to successful remission.

Keywords

• anti-glomerular basement membrane; anti-neutrophil cytoplasmic antibody; rapidly progressive glomerulonephritis; myeloperoxidase; proteinase 3