Epidemiology

• Most common and severe manifestation of lupus nephritis in systemic lupus erythematosus (SLE)
• Also seen with IgA nephropathy and with other inflammatory, autoimmune, or infectious diseases

Pathophysiology

Clinical features

• Can also be nephritic with nephrotic-range proteinuria (nephritic-nephrotic syndrome)
• Can lead to immune complex RPGN

Diagnostics

• ↓ Serum C3 complement levels
• ANA, anti-dsDNA antibodies
• LM
  • Thickening of glomerular capillaries (appear as wire loops)
  • Characterized by increased glomerular cellularity in more than half of the glomeruli
• EM
  • An immunofluorescence pattern containing IgG, IgM, IgA and C3, C1q is highly characteristic of lupus nephritis and is referred to as a full-house (三带一对, ie, a poker hand with three of a kind 3 immunoglobulin classes and two of a kind 2 complement components).
  • The full-house pattern reflects the pathogenesis of lupus: loss of immune tolerance to self-antigens (eg, double-stranded DNA) leads to generation of polyclonal autoantibodies that form circulating immune complexes; these deposit in the glomeruli, where they cause local injury by activating the classical complement cascade.

Treatment