pauci-immune glomerulonephritis

Etiology

• ANCA-associated vasculitis
  • Wegener's granulomatosis
  • microscopic polyangiitis
  • Churg-Strauss syndrome

Epidemiology

• 15-25% of glomerulonephritis

Pathology

• microscopic vessel vasculitis
• necrotizing lesions in glomeruli
• little of no immune deposits
• may occur with or without systemic vasculitis
• ANCA-associated vasculitis

Clinical manifestations

• variable: minimal change with hematuria to rapidly progressive glomerulonephritis
• constitutional symptoms
  • low grade fever
  • myalgia, arthralgia
  • fatigue
• leukocytoclastic vasculitis resulting in palpable purpura
• pulmonary infiltrates to pulmonary hemorrhage

Laboratory

• anti-neutrophil cytoplasmic antibody (ANCA)
• urinalysis: hematura
• serum complement: normal

Diagnostic procedures

• renal biopsy
  • absent or minimal staining for immunoglobulin

Complications

• frequent cause of rapidly progressive glomerulonephritis

Management

• induction with glucocorticoids plus cyclophosphamide +/- plasmapheresis
  • rituximab may be as effective & safer than cyclophosphamide in patients with mild-moderate disease

maintenance with azathioprine, mycophenolate, or methotrexate

prognosis -older age, severe pulmonary disease, & severe renal failure at presentation portend poor prognosis

More general terms

• glomerulonephritis (GN, nephritic syndrome)