Orris

I want mechanism of Glomerulonephritis

Reading File
Finding Sources
Finding Sources
Reading File
Reading File
Reading File
Reading File
Reading File
Loading Image
Glomerulonephritis (GN) is mainly an immune-mediated injury of the glomerulus.

Core mechanism

  1. Immune trigger
  • Infection-related antigens (for example post-streptococcal)
  • Autoantigens (for example GBM components, PLA2R)
  • Systemic immune disease (for example lupus, IgA disorders)
  • ANCA-associated small-vessel vasculitis
  1. Immune attack in the glomerulus
  • Immune complex deposition in glomerular structures:
    • Mesangial
    • Subendothelial
    • Subepithelial
  • Or in-situ antibody binding to intrinsic glomerular antigens (for example anti-GBM disease)
  • Or pauci-immune injury where circulating ANCAs activate neutrophils and damage capillary walls despite little immune deposition on IF
  1. Effector pathways of injury
  • Complement activation (especially C3 pathways in many forms)
  • Leukocyte recruitment (neutrophils, monocytes, macrophages)
  • Cytokines, oxidants, proteases, and membrane attack complex-mediated damage
  • Podocyte and endothelial injury leading to barrier failure
  1. Structural consequences in glomerulus
  • Increased permeability -> hematuria and proteinuria
  • Endocapillary/mesangial hypercellularity
  • Capillary wall injury/necrosis
  • GBM rupture in severe cases -> fibrin leakage into Bowman space -> crescent formation (rapidly progressive GN)
  1. Progression to chronic kidney disease
  • Ongoing inflammation and nephron loss drive:
    • Glomerulosclerosis
    • Tubulointerstitial fibrosis
  • Proteinuria itself worsens tubular/interstitial injury and accelerates decline in GFR

Mechanistic patterns by GN type (high-yield)

  • Immune-complex GN: granular IF pattern; deposits can be mesangial/subendothelial/subepithelial
  • Anti-GBM GN: linear IgG along GBM (type II hypersensitivity-like pattern)
  • Pauci-immune (ANCA) GN: severe necrotizing crescentic GN with minimal immune deposits on IF
  • IgA nephropathy: mesangial IgA immune deposition with complement-mediated inflammation

Simple one-line summary

GN happens when immune mechanisms target the glomerular filtration unit, activate complement and inflammatory cells, damage capillary/GBM/podocyte structures, and lead from acute inflammation to sclerosis and fibrosis if injury persists.
Glomerular microanatomy and filtration barrier
Sources:
  • Robbins, Cotran & Kumar Pathologic Basis of Disease, p. 833-839
  • Smith and Tanagho's General Urology, 19th Edition, p. 2454-2487
  • Comprehensive Clinical Nephrology, 7th Edition, p. 345
This is a shared conversation. Sign in to Orris to start your own chat.