20 - Glomerular Disease 2 Flashcards
minimal change disease etiology/pathogenesis
etiology unknown
thought to involve T cell derived circulating permeability factor that directly damages podocytes and permeability barrier
who gets minimal change disease?
children (most common nephrotic syndrome in children)
adults in 5th-6th decade
males > females
presentation of minimal change disease
nephrotic syndrome
sudden onset proteinuria and edema
otherwise nl renal function
HTN and hematuria UNcommon
minimal change disease lab findings
hypoalbuminemia, nl complement
minimal change disease biopsy findings
LM - nl glomeruli
EM - podocyte foot process effacement/fusion
IF - negative
focal segmental glomerulosclerosis etiology/pathogenesis
primary idiopathic cases due to circulating factor (SuPAR) that directly injures podocytes
who gets focal segmental glomerulosclerosis?
young adults
also can be seen in kids w/ minimal change disease that relapses
more common in african americans
people w/ HIV, obesity, heroin use
presentation of focal segmental glomerulosclerosis
nephrotic syndrome
may have HTN, renal failure or microhematuria
focal segmental glomerulosclerosis lab findings
hypoalbuminemia
nl complement levels
focal segmental glomerulosclerosis biopsy findings
LM - focal sclerosis (duh), only part of glomerulus affected (segmental)
EM - podocyte foot process effacement/fusion
IF - negative
membranous nephropathy etiology/pathogenesis
autoimmune - ab directed against phospholipase A2 receptor on podocytes
immune complex deposition and complement activation
who gets membranous nephropathy?
MCC idiopathic nephrotic syndrome in adults (5th-6th decades peak)
males > females
most idiopathic, but some assoc w/ cancer (lung, breast, GI), hep B, SLE
clinical presentation of membranous nephropathy
nephrotic syndrome
HTN and renal failure UNcommon
membranous nephropathy lab findings
hypoalbuminemia
nl complement
check for assoc conditions (hep, ANA, cancer)
membranous nephropathy biopsy findings
LM - thickening of glomerular BM
EM - subepithelial immune deposits
IF - granular deposits of Ig and complement along BM
membranoproliferative GN etiology/pathogenesis
immune mediated glomerular injury
trapping circulating immune complexes > complement activation
circulating “nephritic factor” spontaneously activates complement on capillary wall
who gets membranoproliferative GN?
any age
female > male
often assoc w/ hep C**, other infections, SLE, cryoglobulinemia
presentation of membranoproliferative GN
nephrotic syndrome
many also have nephritic syndrome
HTN (often early)
membranoproliferative GN lab findings
low complement
if assoc w/ HCV - cryoglobulins, rheumatoid factor
membranoproliferative GN biopsy findings
LM - thickening of glomerular BM, glomerular cell prolif (usually mesangial)
EM - subendothelial immune deposits
IF - subendothelial pattern of C3 and IgG
postinfectious GN etiology/pathogenesis
usually after group A strep infxn
circulating immune complexes from response to infxn lodge in glomeruli > activate complement
how long does it take to get postinfectious GN?
14-21 d after infxn (sooner for throat than skin)
presentation of postinfectious GN
nephritic syndrome
edema, sudden weight gain in children
HTN - often severe
renal failure common
postinfectious GN lab findings
pos ASO titer, pos streptozyme
low complement levels
postinfectious GN biopsy findings
LM - diffuse prolif and inflam
EM - subepitheial “humps”
IF - lumpy-bumpy IgG and C3 deposits
IgA nephropathy etiology/pathogenesis
immune mediated - IgA containing complexes
deposit in mesangium
who gets IgA nephropathy?
MCC primary glomeulonephritis young adults asians and caucasians > blacks male > female may have simultaneous pharyngitic or GI viral infxn
presentation of IgA nephropathy
asymptomatic hematuria, nonnephrotic proteinuria, nl or mildly reduced renal fn
rarely, will be much more severe
IgA nephropathy lab findings
inc serum IgA in 50%
nl complement
IgA nephropathy biopsy findings
LM - mesangial cell prolif and matrix expansion
EM - mesangial deposits
IF - globular mesagial IgA deposits
Anti-GBM nephritis etiology/pathogenesis
ab against type 4 collagen in glomerular BM
may be accompanied by pulm hemorrhage (Goodpasture’s syndrome)
who gets Anti-GBM nephritis?
young adults
male > female
assoc w/ autoimmune disorders (goodpasture, ANCA assoc vasculitis)
presentation of Anti-GBM nephritis
rapidly progressive glomerulonephritis w/ crescent formation
Anti-GBM nephritis lab findings
pos anti-GBM ab
nl complements
Anti-GBM nephritis biopsy findings
LM - crescent formation
EM - breaks in glomerular BM, no deposits
IF - linear IgG deposits along BM
