Nephrotic Syndrome Pathology Flashcards
If your only pathological finding is foot process fusion, what is the dx?
minimal change disease
The primary protein in the slit diaphragm has recently been identified and is termed _____.
nephrin
Why are pts with nephrotic syndrome at an increased risk of infection?
loss of IgG and complement (esp. factor B) into the urine
What is the prognosis for minimal change disease?
good
What is the major abnormality that defines nephritic syndrome?
active inflammation within the glomerulus that leads to damage and subsequent loss of filtration and a reduced GFR
Why do children with nephrotic syndrome have poor growth and osteomalacia?
loss of vitamin D and its binding protein in the urine
What causes FSGS?
a circulating factor that affects the podocyte (maybe suPAR)
Name 3 properties of mesangial cells.
- secretes a basement membrane-like matrix which acts as a structural support to the glomerulus
- has smooth muscle-like properties and can contract, thus affecting capillary surface area and filtration
- has some macrophage-like properties including the ability to secrete cytokines, growth factors, proteases and oxidants
What does a “Maltese cross” under polarized light indicate?
lipiduria, indicative of nephrotic syndrome
What is the most common cause of nephrotic syndrome in adults?
diabetic nephropathy
______ is a type of nephrotic syndrome and the most common one in young adults and African Americans.
FSGS
What are the following associations common to?
- HBV
- gold and penicillamine drugs
- lupus (type V)
- cancer
Membranous Nephropathy
What do these path findings indicate?
- thickening of the GBM by light microscopy with dense, subepi deposits
- Spikes and domes along the BM
- IF positive for immunoglobulin and C3 and C5b-9
Membranous nephropathy
What is Type I MPGN?
IgG and C3 immune complex deposition in the capillary walls and mesangium
What is the tx for FSGS?
long term steroids and cyclosporine
How does Membranous nephropathy occur?
autoimmune mediated by an antibody directed against an antigen (PLA2) on the podocyte
A mutation in the ______ gene is responsible for the congenital nephrotic syndrome of the Finish type.
nephrin
Which nephrotic syndrome often presents like a nephritic syndrome?
MPGN
_______ is an immune mediated glomerular disease associated with immune complex deposits in the subepithelial space
Membranous nephropathy
The most important barrier to protein is the ______.
filtration slit diaphragm
Why are pts with nephrotic syndrome at an increased risk of thrombosis?
- increase in synthesis of coagulation factors (fibrinogen, factors V, VIII, IX, X) by the liver
- urinary loss of anti-thrombin III
- increased platelet aggregability
- impairment of the fibrinolytic system
These underlying conditions are all common to?
- prior minimal change disease
- heroin
- HIV infection
- sickle cell disease
- parvo virus infection
- obesity
FSGS
How does minimal change disease pt present?
- edema
- hx of allergic disease
- severe hypoalbuminemia
- possible Hodgkin’s disease
What are some known associations to MPGN development?
HCV
What is the prognosis for FSGS?
poor
How is vitamin D measured in the blood?
by measuring ionized calcium and 25-0H vitamin D levels
IgG and C3 immune complex deposition in the capillary walls and mesangium would indicate?
type I MPGN
A mutation in the nephrin gene is responsible for ________.
congenital nephrotic syndrome of the Finish type
What is the prognosis for MPGN?
poor
What is the tx for minimal change disease?
steroids (ie prednisone- should have rapid response. if not = prednisone and cyclophosphamide)
C3 deposition only with the BM replaced by dense deposits would indicate?
Type II MPGN
What do these path. findings indicate?
- Light microscopy shows segmental scarring (sclerosis) in some (focal) glomeruli
- Immunofluourescence shows some nonspecific staining of IgM and C3
- EM shows diffuse foot process fusion consistent with a generalized capillary wall defect
FSGS
What is the tx for Membranous Nephropathy?
- Steroids
- cytotoxic drugs (chlorambucil, cyclophosphamide)
- ACE-I
Nephritic syndrome presents with?
- microhematuria and occasionally red cell casts
- non-nephrotic proteinuria
- decreased GFR
- HTN
- edema
Name 4 systemic diseases associated with nephrotic syndrome.
- Diabetes
- Amyloid
- Light Chain Deposition Disease
- Lupus (SLE) Membranous Type V
Name 3 components of the glomerular basement membrane.
- type IV collagen
- laminin and entactin (glycoproteins important in endothelial and epithelial cell attachment)
- heparan sulfate (proteoglycan important in providing a negative charge to the GBM)
______ is the most common cause of idiopathic nephrotic syndrome in children.
Minimal change disease
The Nephrotic syndrome results as a consequence of marked albuminuria (>3.5g/d), which leads to ____ and ____.
hypoalbuminemia and edema
What can minimal change disease progress into?
FSGS
What is thought to be the cause of minimal change disease?
a circulating T cell product that damages the podocyte and permeability layer
Nephrotic range proteinuria almost always means that there is a disruption of the ______.
slit diaphragm
_______ is the most common cause of idiopathic nephrotic syndrome in older adults, esp males.
Membranous nephropathy
What is Type II MPGN?
C3 deposition only; BM replaced by dense deposits
Name 4 associations with Membranous Nephropathy.
- HBV
- gold and penicillamine drugs
- lupus (type V)
- cancer
Why does hyperlipidemia occur in nephrotic syndrome?
- increased lipoprotein synthesis (VLDL, LDL) in the liver
- decreased peripheral removal of VLDL
What is the major abnormality that defines nephrotic syndrome?
an excessive leak of protein through the glomerular capillary wall into the urinary space
These characteristics define what disorder?
- Proteinuria (>3.5 gm/day or >40 mg/hr/M2 in children)
- Hypoalbuminemia (
- Edema
- Hyperlipidemia
- Lipiduria
nephrotic syndrome
What are some s/s of acute renal vein thrombosis?
- flank pain
- an enlarged kidney by ultrasound
- hematuria
Minimal change disease is the most common cause of idiopathic nephrotic syndrome in _____.
children
Nephritic or nephrotic: Minimal change disease
nephrotic
What is the prognosis for membranous nephropathy?
poor
What are some underlying associations to FSGS development?
- prior minimal change disease
- heroin
- HIV infection
- sickle cell disease
- parvo virus infection obesity
What is the tx for MPGN?
- alternate day steroids
- anti-platelets
- treatment of HCV if present
Membranous nephropathy is the most common cause of idiopathic nephrotic syndrome in ______.
older adults, esp males
