Protinuria Flashcards
(27 cards)
Bubbles on the surface of the urine indicate kidney disease
T or f
T
Increase in [protein] causes decrease in surface tension and more bubble stability
Glomerulus depends ONLY on the size of the protein in the restriction process
F
N glomerulus depends on both size and electrical charge to restrict filtration of protein
Many cellular layers rather than GBM alone form a barrier
T
-Fenestrations in endothelial cells : size 400-800A (macromolecules are <100A)
-slit diaphragm between podocytes
GBM is negatively charged so it allows the passage of proteins
F
GBM is -vely charged (heparan sulfate)
Albumin is -vely charged
So albumin can’t pass
What does the combined impairment of both carrier charge selectivity and size selectivity result in
It results in massive proteinuria observed in nephrotic pt
Define nephrotic syndrome
-hyperalbiminuria
-hypoalbinimia
-edema
Periorbital area, genitalia and lumbar fossa in sleeping position
Edema on lower limbs and ascites in standing position
-dyslipidemia (due to inc liver production of albumin and lipids)
Most common cause of nephrotic syndrome in children
Minimal change kidney dz
What is given as a trial to confirm the minimal change kidney dz
Steroid trial
If no response—> other differential
Pathophysiology of proteinuria depends on 2 factors
-hemodynamic factors
-proximal tubules
Pathophysio behind hemodynamic factors
Proteins can overcome the charge selective barrier when intraglomerular P is high ( inc in AT ):
-CHF
-HTN
-orthostatic proteinuria
-ex related proteinuria
-loss of nephron mass
The proteinuria due to problem in proximal convoluted tubule is mainly due to problem in either: resorption , degradation or catabolism of proteins
T or f
T
What is the major constituent of non plasma protein in urine
Tamm horsefall protein secreted by tubular cells and it has no clinical significance
What are the types of proteinuria
-glomerular
-tubular
-overflow
Starting with glomerular proteinuria
What is the best independent predictor for ESRD
excretion rate of urinary proteins and/or albumin
Tubular proteinuria is characterized by impaired proximal tubular resorption of LMW protein
T or f
T
What are the situations that can cause tubulopathies
-heavy metal intoxication
-drug intoxication (aminoglycoside)
-detoni- debre fanconi synd
-deton -debre fanconi dz
Cysteinosis which is a lysosomal storage dz in which cysteine is unable to come out of lysosome —> build up—> death of cells in prox tubules and other cells—> no resorption of glucose; aa; protein; uric acid and phosphate and mostly BICARB
—> metabolic acidosis
—> H+ sits on Ca2+ R
Tx : give phosphate and bicarb
3) Overflow proteinuria is due to the increase in filtered protein load that results in significant proteinuria and develops accompanying hemoglobinuria and myoglobinuria as well as multiple myeloma
T
How do we quantify urinary proteins
-Reagent test strips
-protein/creatinine ratio
Positive dipstick screening for proteinuria shouldn’t be repeated
T or f
F
Positive dipstick screening for proteinuria must be repeated and warrants quantification of proteinuria
Protein/ creatinine ratio should be measured in a sample collected during 24h
T or f
F
Measued in a random urine sample (during 1st or 2nd morning urine sample are the most suitable)
Types of proteinuria :
1) Define Orthostatic proteinuria
We don’t have proteinuria in the morning but whenever we are walking or standing we will have it
Confirmed by comparing morning sample to another urine sample collected during the day
Orth proteinuria is so severe and needs med tx
F
It is usually mild and non selective
Often occurs in slender adolescents
Excelent prognosis
No tx is needed
2) transient proteinuria define
Associated with: ex, fever, stress, dehydration
Doesn’t reflect renal dz
