Clinical Chemistries: Kidney Assays Flashcards
What are the four blood kidney assays that are run?
Blood Urea Nitrogen
Creatinine
Symmetric dimethylarginine
Uric Acid (birds)
What is the urine kidney assay?
Urine Protein/Creatinine Ratio
What are the functions of the urinary system?
Eliminates waste products in the urine
Produces and affected by hormones
Maintains blood homeostasis
How does the urinary system maintain blood homeostasis?
Regulates blood pH, blood volume, blood pressure, and electrolytes
What is reabsorbed into the body?
100% glucose
80% water
70% potassium
50% urea
Where does reabsorption occur?
The proximal convoluted tubule
What is secreted into the urine?
Hydrogen
Bicarbonate
Where does secretion occur?
The distal convoluted tubule
What does BUN stand for?
Blood Urea Nitrogen
What is Urea?
The end product of protein metabolism
What is filtered through the glomerulus into the renal tubules?
Urea
What happens if the kidney is not functioning normally?
Urea is not eliminated
High BUN and the animal feels sick
What are the other causes of high BUN?
High protein diet
Strenuous exercise
Dehydration
How does a high protein diet cause high BUN?
An increase in protein metabolism leads to high production of urea
How does strenuous exercise cause high BUN?
An increase in muscle break-down increases urea
How does dehydration cause high BUN?
The kidneys are conserving water leading to retention of urea
Where is Creatinine formed from?
The creatine in skeletal muscle
What is creatinine?
The breakdown product of muscle metabolism
What happens if the glomerular filtration rate (GFR) decreases?
Creatinine levels will increase because it is normally filtered through the glomerulus
What are the advantages of the BUN and Creatinine tests?
Are the kidneys working normally?
Is the kidney disease progressive?
Is the treatment of kidney disease working?
What are the disadvantages of the BUN and Creatinine test?
They are not a sensitive test
Need 75% kidney damaged before you see an increase
GFR can be 1/4 of the normal rate before an increase
How many dogs are diagnosed with kidney disease?
1 in 285
How many cats are diagnosed with kidney disease?
1 in 43
What is an increase in BUN and Creatinine called?
Azotemia
What are the clinical signs of kidney disease?
PU/PD Decreased appetite Weight loss Bad breath Vomiting and diarrhea Sore mouth Weakness Lethargy
What is the newer kidney function test?
Symmetric dimethylarginine (SDMA)
What does SDMA detect?
The loss of renal function at as little as 25%
Usually around 40%
Is the BUN/Creatinine ratio useful in diagnosing kidney disease?
No, because both have a wide range of intervals
Useful when assessing patient status during treatments
Urine Protein/Creatinine Ratio in healthy animals
The level of protein and creatinine excreted into urine are constant and nearly equal
What happens if there is a problem with the glomerulus?
Proteins leak
What is the degree of proteinuria directly related to?
The degree of renal failure
What is the normal Urine protein/creatinine ratio in healthy dogs
Less than 1
What is the urine protein/creatinine ratio in prerenal or functional origin?
Between 1 and 5
What is the urine protein/creatinine ratio for renal disease?
Greater than 5
