Nephritic vs. Nephrotic syndromes for the USMLE CK exam
Nephritic and Nephrotic Syndromes:
Nephrotic: Defined by – hyperproteinuria, hypoproteinemia, hyperlipidemia, edema
- Proteinuria >3.5g/day
- Patient has generalized edema
- Decreased albumin
- Best initial test is a urinalysis showing significantly increased levels of protein
- Next best step is a spot-urine test for a protein: creatinine >3.5:1
- 24-hr urine protein collection >3.5g
- Most accurate test – Renal biopsy
|TYPE OF NEPHROTIC DISEASE||COMMON CHARACTERISTICS/TX|
|Minimal Change Disease||This is seen in young children.
Treat with prednisone
|Focal Segmental Glomerulosclerosis||Similar in presentation to MCD but occurs in adults.
Most commonly idiopathic.
Commonly presents in young hypertensive males.
Treat with prednisone and cyclophosphamide
|Membranous Glomerulonephritis||Is the most common 1° cause of nephritic syndrome in adults.
A slowly progressive disorder.
Many causes: HBV, HCV, syphilis, certain drugs, malignancies, SLE.
Treat with prednisone + cyclophosphamide.
50% of cases progress to end-stage renal failure
|Membranoproliferative Glomerulonephritis||Type 1 is slowly progressive while Type 2 is aggressive.
Autoantibody against C3 convertase (decr C3 levels)
Treat with prednisone, plasmapharesis.
- Protein and salt restriction
- HMG-CoA reductase inhibitor for hyperlipidemia
- This happens when there is diffuse glomerular inflammation
Signs and Symptoms:
- There is an acute-onset of hematuria
- Decreased GFR
- Increased Bun:Cr
|TYPE OF NEPHRITIC DISEASE||COMMON CHARACTERISTICS/TX|
|Post-streptococcal Glomerulonephritis||An acute condition.
Classically occurs after Strep Pyogenes infection.
Immunofluorescence shows coarse granular IgG or C3 deposits.
Labs show increased red cells and casts, decreased serum C3, incr ASO titer.
|Rapidly Progressive Glomerulonephritis (Crescentic)||A nephritic condition that progresses rapidly to renal failure.
Goodpasture’s disease is in this category.
Immunofluorescence shows smooth and linear IgG deposits.
Treat with prednisone and plasmapharesis.
|Berger’s Disease (IgA nephropathy)||Most common type of nephropathy.
IgA deposits in mesangium.
Presents with recurrent hematuria + low-grade proteinuria.
Usually harmless, however 1 in 4 may progress to renal failure.
Treat with prednisone
|Henoch-Schonlein Purpura||Always in children, is an IgA nephropathy.
Presents with abdominal pain, GI bleed, vomiting, and hematuria.
Classically find palpable purpura on buttocks and legs
Is a self-limiting disease that requires no steroids.
|Multiple Myeloma||There is an increased light-chain production.
Find Bence-Jones protein in urine.
Patient becomes succeptible to encapsulated bacteria because there is a defect in normal antibody production.
Treatment must be on the underlying myeloma.