10.28: Renal III Flashcards
What is MCD?
- Minimal change disease
- Present with generalized and periorbital edema
- Common in 2 - 6 yo: 95% of their nephROTIC synd.
What is FSGS?
Focal and Segmental Glomerulosclerosis
What is assumed diagnosis in child with nephrotic syndrome?
- MCD
- If course is normal and uncomplicated no biopsy is necessary
- ***If it is determined that it is resistant steroids, biopsy performed
Is biopsy necessary in adults / kids for nephrotic syndrome?
Adults: Yes
Child: No, assumed MCD
Pathogenesis of MGD?
- Reversible injury of unknown origin to podocytes of epithelial cells of basement membrane
- No more more slit membranes allowing albumin leak
What type of immune complex is involved in MCD?
- No IC involvement
- No inflammation
What does MCD disease usually occur after?
- NSAIDs
2, Viral infection - Hodgkins
What is podocyte effacement?
- Injury to epithelial cells of basement membrane
- Causes the feet to fuse losing slit membrane
- Allows proteins to pass through: nephrotic syndrome
Prognosis of MCD?
- Recurrent episodes of nephrotic syndrome
- Stops at puberty
- Treat with steroids to reverse podocyte injury
Treatment for membranous nephrotic syndrome?
- Very hard to treat
- MCD is treated easily with steroids
General presentation of MCD?
- Child
- Proteinuria: foamy urine
- ***Can be less than 3g in child
- Periorbital and generalized edema
- Lipiduria
What is effacement of podocytes characteristics of?
MCD
Differential diagnosis of 7-8 yo with nephrotic syndrome??
- 75% chance MCD
2. FSGS
Selective vs. nonselective proteinuria?
Selective: only albumin
Non selective: proteins other than albumin as well
**Usually indicative of greater degree of renal injury
FSGS presentation?
- Nephrotic syndrome
- Higher incidence of hematuria
- Proteinuria is often non selective
DIfference in injury between FSGS and MCD?
MCD: Reversible injury to podocytes w. steroid treatment
FSGS: Injury is irreversible
Progression of FSGS?
- Initially only glomeruli in juxtmed. involved
- Eventually all will be involved: global sclerosis leading to tubular atrophy and interstitial fibrosis
- Will progress to renal failure
Treatment of FSGS?
- Initially responds to steroids
- Becomes dependant, then resistant
Creatinine levels in FSGS?
Rising serum creatinine
Possible etiologies of FSGS?
- Idiopathic
- HIV
- Parvovirus B19
- Heroin
- Sickle cell disease
- Obesity
- Low birthweight
- Bodybuilding steroids
- HTN
- Mutation in proteins for slit diaphragms
What occurs in HIV associated FSGS?
- Collapse of tuft and proliferation of visceral epithelium
- Rapid progression to failure with very poor prognosis
“Collapsing FSGS”
When is immune complex seen in nephrotic syndrome?
- Membranous nephropathy
- Autoimmune and resistant to steroids
Two disease associated with nephrotic syndrome w/ hematuria?
- MPGN: Membranoproliferative glomerulonephritis
2. DDD: “Dense Deposit Disease”
Etiology of MPGN?
Primary IC formation with complex activation, secondary to:
- Chronic immune disorders
- Hepatitis
- Endocarditis
- Chronic Bacterial infections
- Plasma cell monoclonal protein production
What is thick basement memb. w/ “double contour or tram track” on silver stain indicative of?
MPGN
Characteristics of MPGN?
- Thick Basement memb. with IgG + complement
- Low serum complement
- Progression to renal failure
- Try to treat underlying disease causing
Etiology of DDD?
- Sustained activation of complement via alt. pathway
- No antibodies seen / no antigen antibody
- Dense deposits in lamina densa
- C3 convertase stabilization leading to comp. activation
Determination of kidney needle biopsy?
- Almost always needed in adults
- Usually only in kids if doesn’t respond to treatment
What happens to glomeruli in diabetes?
- Nonenzymatic glycosylation of vascular basement membrane leading to hyaline arteriosclerosis
1. Narrows lumen
2. Prevents nutrient diffusion through membrane
3. Makes leaky and more porous
Where is thickening of membrane in diabetes particular too?
- Efferent artery
- Increases glomerular pressure
What is amyloidosis?
- Deposits of abnormally folded beta pleated sheets
- Appears congo red positive and apple green under polarized light
- Most often associated with multiple myeloma or plasma cells
What is congo red positive indicative of?
Amyloidosis
How is amyloidosis diagnosed?
- Tissue biopsy of Fat of kidney tissue
What is myeloma?
Cancer of plasma cells
Who is lupus more common in?
Women
Histology in early FSGS?
Parts of glomerular tufts obliterated capillaries
