Glomerulonephritis Flashcards
6 clinical hallmarks of acute nephritis
hematuria with deformed red cells, red‐cell casts in urine acute decline in renal function proteinuria HTN edema
Cause of edema in acute nephritis
volume overload by reduction of GFR
Glomerulonephritis vs. glomerulopathy
Glomerulopathy is a non-proliferative disease of glomerulous.
Glomerulonephritis manifests cellular proliferation and inflammation of glomeruli
4 causes of primary glomerulonephritis
Acute post infectious (particularly strep)
IgA nephropathy
Anti-GBM disease
Membranoproliferative glomerulonephritis
4 systemic diseases w/ glomerulonephritis
Lupus nephritis
Microscopic polyangiitis
Wegener’s granulomatosis (this is the one they want to rename because of the Nazi)
Cryoglobulinemic glomerulonephritis
Goals of therapy
- BP control
- reduction of proteinuria preferably w/ blockage of RAAS
- immunosuppression targeting underlying dz process
Three major types of proliferative response of kidney
1) Mesangial (involving mesangial stock only)
2) endocapillary (causing occlusion of glomerular capillary lumina by prolif of endo and mesangial cells and leukocyte infiltration)
3) extracapillary (prolif of parietal cells leading to formation of crescents outside glomerular tuft). Crescentic forms are most severe.
Post strep GN timing
10-14 days after infection w/ nephritogenic strain, typically A beta-hemolytic strep (exotoxin B is causitive antigen).
Can also because post other infections, like endocarditis
Post Strep GN pathology
Endocapillary proliferative lesions, infiltrating neutrophils w/ subepithelial humps on EM and granular IgG and C3 on immunofluorescence
Post Strep test
Low C3 and positive serology for strep
IgA nephropathy age group?
Usually 2nd or 3rd decade of life
IgA pathology
mesangial proliferation on light microscopy, w/ deposition of immune complexes predominantly containing IgA
IgA presentation
Gross or microscopic hematuria (after exercise or URI), variable degrees of proteinuria. About 20% develop end stage renal failure over 20 years.
Henoch-Schonlein Purpura
Systemic form of IgA nephropathy, characterized by purpuric rash in LE, GI symptoms, arthritis and glomerulonephritis from IgA nephropathy. Can find IgA deposits in capillaries of skin, GI, kidney.
IgA pathogenesis
Defect in O-glycosylation of hinge region of IgA1, combined by generation of auto-antibodies against these abnormal IgA1 – immune complexes form and deposit in kidney
IgA neph rx
RAAS inhibition. Immunosuppressive only for pts w/ evidence of significant proteinuria and kidney dysfnx
SLE nephritis
Production of anti-DNA antibodies
SLE classical presentation
hematuria/proteinuria and renal failure w/ extrarenal manifestations of SLE (rash, arthritis, serositis)
Serologies for SLE
positive antinuclear antibodies (ANA) and low serum complement
Classic SLE pathology
diffuse endocapillary proliferation w/ wire-loop deposits and hematoxyphil bodies (swollen nuclei altered by complexing to ANA). IgG, IgM, IgA, C3 and C1q (full house) deposition in mesangium and subendothelial regions
Mechanisms of glomerular injury
Majority are immunologically mediated. Prone to injury by immune mechanisms because of high CO, hydrostatic pressure, fenestrated glomerular endothelium, and seiving effect.
Low complement levels (4)
Strep
SLE
membranoproliferative
cryoglobulinemic
Normal complement levels
IgA
ANCA-RPGN/Wegener’s/Microscopic PAN
Anti GBM dz
Nephrotic syndrome (MC, FSGS, Membranous, diabetic, amyloid)
Immunofluorescent staining
Pauci-immune (wegeners)
Granular (lupus)
Linear (goodpasture’s)
