glomerular nephritis + nephrosis Flashcards
group A strep infection (pharyngitis, impetigo) 1-3 wks before glomerulonephritis
children
brown urine “coca-cola”: heme pigment from hematuria
↓ C3 (activated and destroys BM)
↑ anti-streptolysin O (prove recent strep pharyngitis)
↑anti-DNase B (prove recent pharyngitis + impetigo)
poststreptococcal glomerulonephritis
type III hypersensitivity reaction: circulating antibodies bind to streptococcal antigens → immune complexes deposit in glomerulus
poststreptococcal glomerulonephritis
pros/cons of antibiotics for group A strep infection
DON’t prevent: glomerulonephritis
prevent: rheumatic fever + rheumatic heart disease
renal bx of poststreptococcal glomerulonephritis
LM: hypercellular glomeruli, neutrophils
IF: “lumpy-bumpy” deposits of IgG/IgM IC, C3 deposited along GBM and mesangium
EM: “subepithelial humps”
associated with Henoch-Schonlein purpura (vasculitis) triad: palpable purpua on butt + legs arthralagia ab pain - intestinal hemorrhage renal disease
IgA nephropathy (berger disease) - not beurger disease = vasculitis (young, male smoker)
renal bx of IgA nephropathy
↑ serum IgA: IgA IC deposited in mesangium
proliferation of mesangial cells
“lumpy-bumpy” deposits of IgG/IgM IC
“subepithelial humps”
poststreptococcal glomerulonephritis
↑ serum IgA
hematuria
RBC casts
flares after infection (URI) - also occurs in Henoch-Schonlein purpura
IgA nephropathy
defect in type 4 collagen (in BM)
alport syndrome
renal bx of alport syndrome
splitting of BM
triad:
can’t see: cataracts
can’t pee: nephritis
can’t hear high C: deafness (high frequency hearing loss)
alport syndrome
differential diagnosis for rapidly progressive glomerulonephritis (crescentic glomerulonephritis):
crescent shaped deposits in glomeruli (fibrin, complement)
goodpasture syndrome
granulomatosis with polyangiitis
microscopic polyangiitis
lupus
type II HSR (ab against GBM)
goodpasture syndrome
linear IgG on IF (abs against GBM)
goodpasture syndrome
kidney + lung disease
goodpasture syndrome: hematuria + hemoptysis
granulomatosis with polyangiitis (GPA): hematuria + lungs + upper airway (sinus, hard palate), +c-ANCA (PR3-ANCA)
c-ANCA (PR3-ANCA) + crescent shaped deposits in glomeruli (fibrin, complement)
granulomatosis with polyangiitis
p-ANCA (MPO-ANCA) + crescent shaped deposits in glomeruli (fibrin, complement)
microscopic polyangiitis
most severe form of lupus nephritis
diffuse proliferative glomerulonephritis
anti-dsDNA in mesangium + subendothelial associated with
lupus nephritis
renal bx of diffuse proliferative glomerulonephritis (lupus nephritis)
LM:dense, pronounced GBM (due to anti-dsDNA) “wire-looping”
wire-lupus
“wire-looping” in lupus nephritis
diffuse proliferative glomerulonephritis may present as
nephrotic syndrome (heavy proteinuria >3.5 g/day)
renal bx:
flattening or effacement of podocyte foot processes → more permeable to albumin
but relatively NORMAL
minimal change disease
most common cause of nephrotic syndrome in children
minimal change disease
children triggered by infections or immunization hypoalbuminemia edema tx: CS (give empirically w/o biopsy if fit clincial picture)
minimal change disease
most common cause of nephrotic syndrome in adults
focal segmental glomerulosclerosis
nephrotic syndrome in: african americans, latinos adults
HIV patients
becoming most common in US
focal segmental glomerulosclerosis
renal bx:
focal (
focal segmental glomerulosclerosis
most common nephrotic syndrome cause in:
caucasian adults
membranous nephropathy
renal bx:
thickening of BM +
“subepithelial” immune deposits along BM → creates “BM spike + subepithelial dome” appearance
membranous nephropathy
nephrotic syndrome caused by lupus
membranous nephropathy
membranoproliferative glomerulonephritis
hematuria (nephritic sx) heavy proteinuria (nephrotic sx)
membranoproliferative glomerulonephritis
nephritic syndrome caused by lupus
diffuse proliferative glomerulonephritis
renal bx:
membrane proliferates “tram-track” GBM
“subendothelial humps” (vs subepithelial humps poststreptococcal GN
mesangial cell growth: can grow between tracks
membranoproliferative glomerulonephritis
causes of membranoproliferative glomerulonephritis
hep B/C
lupus
subacute bacterial endocarditis
↑ blood glucose → nonenzymatic glycosylation:
glucose binds to Hb, blood vessels, glomerular BM (thick), arterioles (mesangium prolferates)
diabetic nephropathy
microscopic albuminuria
can progress to nephrotic syndrome
diabetic nephropathy
renal bx:
thick GBM
expansion of mesangium
kimmelstiel-wilson nodule (round, pink acellular nodule in glomeruli)
diabetic nephropathy
abnormal amyloid proteins deposited
kidney most commonly involved in systemic amyloidosis
associated with multiple myeloma
amyloidosis
renal bx:
expansion of mesangium + amyloid deposits
amyloidosis
congo red stain: amyloid protein bright green under polarized light (apple green birefringence)
amyloidosis
