Nephrotic Syndromes

Question 1

What is Nephrotic Syndrome?

Answer 1

Damage to Glomerulus
Proteins enter filtrate –> Proteinuria
Hypoalbuminemia
Oval fat bodies

Question 2

Minimal Change Disease

Answer 2

• Most common glomerular disease in children
• Fused foot processes
• Cause usually idiopathic, sometimes associated with lymphoma or leukemia, renal cell carcinoma, or NSAIDS

Question 3

Focal and Segmental Glomerulosclerosis (FSGS)

Answer 3

Most common in African Americans

Sclerosis = scar tissue formation
Segmental = only segment of glomeruli affected
Focal = only some glomeruli in kidney affected

Idiopathic
Hyalinosis due to protein trap in glomerulus

HIV-Associated Nephropathy common cause - declining kidney function is rapid

Question 4

Membranous Nephropathy

Answer 4

• Most common nephrotic syndrome in caucasian adults
• M-type phospholipase A2 receptor antibody = 100% specific to MN

4 things for MN to develop

1. Immune complexes subepithelial deposition (GBM)
2. Complement activation
3. MAC (C5b-9) forms –> damages glomerulus
4. Regulatory proteins disabled

• Diffuse thickening of glomerular basement membrane (GBM)
• Spike and dome pattern on EM

Question 5

Diabetic Nephropathy

Answer 5

Kidney damage by type 1 and type 2 diabetes

• Excess glucose gets into filtrate
• Glucose + eosinophilic material occlude capillaries
• Increase pressure in glomerulus –> hyperfiltration (increase GFR)
• Diffuse or nodular (Kimmelstiel Wilson nodules) glomerulosclerosis (scarring)
• Increase permeability
• Microalbuminuria
• Macroalbuminuria
• Damages glomerulus over time
• GFR decreases
• Proteinuria
• ESRD
• Retinopathy

Question 6

Amyloidosis

Answer 6

Amyloids = Misfolded proteins
Proteins aggregates and deposits in tissues

Primary = AL protein (L = light chain)
Secondary = Serum Amyloid A (messed up amyloid A that's formed in response to infection/inflammation)

Congo red stain –> green birefringence

Triad points to Amyloidosis: Fanconi’s Syndrome, Hyperkalemia, Nephrotic Syndrome

Question 7

Pre-eclampsia

Answer 7

Maternal immune system response to blood supply to placenta due to protein PP-13 deficiency

• Placental Ischemia
• Abnormal prostaglandins, coagulation, and vasoconstriction
• Glomerulus endothelial damage and hyalin deposition
• Increase BP during latter half of pregnancy
• HTN resolves approx. 6 wks after pregnancy