PATH - Nephrotic Syndrome

Question 1

Nephrotic syndrome

Answer 1

NephrOtic syndrome—massive prOteinuria (> 3.5 g/day) with hypoalbuminemia, resulting edema, hyperlipidemia

Frothy urine with fatty casts

Due to podocyte damage disrupting glomerular filtration charge barrier.

Question 2

Minimal change disease (lipoid nephrosis)

Answer 2

Most common cause of nephrotic syndrome
in *children

Often 1° (idiopathic) and may be triggered by recent infection, immunization,
immune stimulus.

EM—*effacement of foot processes
IF⊝

Question 3

Focal segmental

glomerulosclerosis

Answer 3

Most common cause of nephrotic syndrome in
*African Americans and *Hispanics

LM—segmental sclerosis and hyalinosis 
IF—often⊝, but may be ⊕ for nonspecific focal
deposits of IgM, C3, C1..
EM—effacement of foot process similar to
minimal change disease

May progress to chronic renal disease

Question 4

Membranous nephropathy

membranous glomerulonephritis

Answer 4

Most common cause of 1° nephrotic syndrome
in *Caucasian adults

LM—diffuse capillary and GBM thickening
IF—granular as a result of immune complex
deposition. Nephrotic presentation of SLE.
EM—“spike and dome” appearance with
subepithelial deposits.

May progress to chronic
renal disease.

Question 5

Amyloidosis

Answer 5

Kidney is the most commonly involved organ
(systemic amyloidosis)

LM—Congo red stain shows *apple-green birefringence under polarized light due to
*amyloid deposition in the mesangium

Question 6

Diabetic glomerulonephropathy

Answer 6

Most common cause of end-stage renal disease in the United States

Nonenzymatic glycosylation of GBM–>INC permeability, thickening

Nonenzymatic glycosylation of efferent arterioles–>INC GFR–>mesangial expansion

LM—mesangial expansion, GBM thickening,
eosinophilic nodular glomerulosclerosis
(*Kimmelstiel-Wilson lesions)