Nephrotic Syndrome Flashcards
What is the thing to remember about nephrotic syndrome?
The thing to remember for this one is massive proteinuria.
What does this massive proteinuria lead to in nephrotic pts?
hypoalbuminemia -they are peeing out albumin!
Why does hypoalbumemia result in edema?
the oncotic pressure in the blood goes down, and fluid leaks out of the vasculature into the surrounding tissue
What is the fourth feature of nephrotic syndrome (first three- massive prorteinuria, hypoalbuminemia, edema)?
Why does this occur?
hyperlipidemia/hyperlipiduria
Liver is trying to compensate for the loss of protein so its making lipids for this reason.
- Hemodynamic changes cause what kind of changes in the GFR?
- How does this manifest clinically? 2
- a decreased glomerular filtration rate
2. (manifested clinically as oliguria and azotemia).
The hypertension seen in nephritic syndrome is probably a result of what?
2
- fluid retention and
2. increased renin released from ischemic kidneys
Nephrotic Syndrome–Features
5
- Proteinuria—(>3.5 g in 24 hrs)
- Edema
- Hypoalbinemia—(less than 3.0)
- Usually: Hyperlipidemia/hyperlipiduria
- [Glomerulopathy—proteinuria without the rest]
What is the most common disease in nephrotic syndrome in children?
Primarily—Minimal Change Disease (MCD)
Nephritic Syndrome–Features
4
- Hematuria—RBC casts
- Oliguria
- Azotemia
- HTN
Nephrotic syndrome is Defined by the presence of?
5
- Heavy proteinuria** (albuminuria greater than 3.5 g/24 hours)
- Hypoalbuminemia** (less than 3.0 g/dL)
- Peripheral edema***
- Hyperlipidemia and thrombotic disease
- Few cells or casts in the urine
Etiologies in adults?
6
Adults
- Systemic diseases such as diabetes mellitus, amyloidosis, HIV and SLE [Lupus] (30%) in adults
- NSAIDs
- Minimal Change Disease (MCD)
- Segmental Focal
- Glomerulosclerosis (SFG)
- Membranous Nephropathy
Nephrotic Syndrome Pathophysiology
6 steps
- glomerular damage
- increased permeability of glomerular capillaries to protein
- Proteinuria leads to less protein in the blood
- Hypoproteinuria leads to increase in plasma oncotic pressure
- this decreases plasma volume, GFR
- Aldosterone is secreted and fluid is retained
Name the steps that must occur to reach nephrotic syndrome?
6
1. Massive proteinuria leads to 2. Decrease in plasma proteins leads to 3. Fluid shift leads to 4. decrease in plasma volume leads to 5. Decrease in GFR leads to 6. Increase aldosterone secretion which will also promote edema
What is the function of the glomerular capillary wall?
2
- Electrostatically prevents negatively charged proteins from passing through
- Podocyte intercellular junctions restrict the passage of proteins of certain molecular weight sizes
Most nephrotic disease there is damage to the GCW that results in?
2
- Loss of charge to prevent proteins from passing
2. Damage to podocyte structure so loss of selection due to size restriction
What is proteinuria?
Increased filtration of macromolecules across the glomerular capillary wall**
What proteins are lost? 5
This protein loss results in what? 3
- Albumin
- Clotting factors
- Transferrin
- Immunoglobulins
- Vitamin D binding Protein
- Results in decreased levels of
Vitamin D - This decreases serum calcium levels
- Which raises the level of PTH
- Hypoalbinemia is partially due to what?
- Also thought that albumin is catabolized where?
- The low oncotic pressure stimulates what?
- Partially due to loss of albumin through the glomeruli
- Also thought that albumin is catabolized in the proximal tubular cells of the kidney
- hepatic lipoprotein synthesis leading to hyperlipidemia
- How Does nephrotic syndrome affect LDL, TGC, HDL levels?
- How does nephrotic syndrome affect hepatic syntheis and peripheral metabolism?
- This all increases the risk of what?
- What will we find in the urine at this point? (what are these called?)
- Elevated levels of LDL and triglycerides (HDL usually normal)
- Increased hepatic synthesis and decreased peripheral metabolism
- Increases risk of cardiovascular disease*
- Lipiduria (presence of oval fat bodies in urine)
Minimal Change Disease:
1. Can occur in adults secondary to use of what?
- What will you find in Minimal change that is different from other forms of Nephrotic syndrome? 3
- NSAIDS
- Find only mild mesangial cell proliferation
- No immune deposits
- Flattened podocytes
Etiologies of MCD
5
- Infections
- Drugs
- Tumors
- Allergies
- Other diseases
- What drugs can cause MCD? 3
- What kind of tumors can cause MCD? 2
- What kind of allergies can cause MCD? 3
- WHta other diseases can cause MCD? 2
- NSAIDS
- Lithium
- Ampicilln
- Hodgkin’s
- Leukemia
- food
- bee stings
- pollens
- Following allogenic stem cell for leukemia
- Following hematopoietic cell transplantation
Treatment for MCD?
steriods/prednisone
- Most common lesion found in those with idiopathic nephrotic syndrome 35% of the time [Blacks—50%] is what?
- What is this disease characterized by? 2
- What are the two forms?
- Focal Segmental Glomerulosclerosis (FSGS):
- Characterized by the presence in SOME glomeruli of segmental areas of
- mesangial collapse and
- SCLEROSIS - Can be primary and secondary forms
Secondary Causes of FSGS
6
- HIV infection
- Obesity
- Lupus
- Diabetes
- Chemicals that harm the kidneys
- Meds