1/ Nephritic syndrome is an inflammatory response
- Characterized by glomerular capillary rupture leading to (1) mild edema, (2) mild proteinuria, (3) hematuria, (4) azotemia, (5) oliguria, and (6) hypertension.
- occurs with increased basement membrane permeability that presents with edema, massive proteinuria (especially low-weight proteins like albumin), and hyperlipidemia.
- sudden onset of hematuria (brown urine), decrease in GFR leading to azotemia, oliguria, HTN, and edema. Proteinuria is mild, hematuria is very large, RBCs and WBCs are present, RBC casts and granular casts are present, but no lipids are in the urine.
2/ Nephrotic syndrome is (1) proteinuria > 3.5 g/day, (2) anasarca, (3) lipiduria with hyperlipidemia, hypoalbuminemia, hypercoagulation state.
- The proteinuria is due to changes in the GBM that decrease charge selectivity, size selectivity, or increase permeability.
- ApoB lipoprotein production and decreased catabolism leads to the hyperlipidemia.
- A physical finding in nephrotic syndrome is Muehrke’s nails, or horizontal white bands on all fingernails associated with low serum albumin.
- Heavy proteinuria, mild hematuria, no cells, fatty casts, and free fat droplets are present in the urine.
* Notes:
Inflammation = nephritic syndrome.
Capillary changes = nephritic syndrome.
Azotemia and oliguria = nephritic syndrome.
Nephritic syndrome – immune, inflammation, I can’t pee, I can’t see (HTN).
Nephrotic syndrome = piss it all away and get fat (edema and hyperlipidemia).
Massive proteinuria = nephrotic syndrome.
Glomerular basement membrane changes = nephrotic syndrome.
source:www.clinicalreview.com
* Nephritic syndrome:
- Characterized by:
1. Hematuria
2. Red cell casts in urine
3. Moderate proteinuria
4. Edema
5. Hypertension
6. Oliguria (occasionally)
- Due to immunological damage to the glomerular basement membrane, causes are unknown, except for Acute poststreptococcal glomerulonephritis.
- 3 forms to occur:
1. Acute Glomerulonephritis (AGN) --> reversible and self-limiting
2. Rapidly Progessive Glomerulonephritis (RPGN) --> weeks or months to Chronic Renal Failure
3. Chronic Glomerulonephritis (CGN) --> years or dacades to Chronic Renal Failure
* Nephrotic syndrome:
- Characterized by:
1. Hypoalbuminemia (due to heavy proeinuria)
2. Edema (b/c plasma oncotic pressure decreases due to hypoalbuminemia)
3. Hyperlipidemia (b/c the recuction in plasma oncotic pressure stimulates hepatic lipoprotein systhesis)
4. Microcytic hypochromic anemia (due to urinary loss of transferrin)
5. Increased tendency to thrombosis, especially of renal veins (due to urinary loss of antithrombin III)
6. Vitamin D deficiency (due to urinary loss of Cholecalciferol - binding protein)
7. Thyroid abnormalities (due to urinary loss of thyroid - binding globulin)
8. Susseptibility to infections (due to urinary loss of IgG)
- Causes:
1. If immunological origin, usually due to unknown causes.
2. Some cases are secondary to known causes, such as: Diabetes mellitus, amyloidosism exposure to allergens (e.g., bee stings), toxins (e.g., mercury)
Source: Principles of medical physiology by Sabyasachi Sircar, page 421
