Urinalysis Flashcards
3 Major components of complete UA
- Physical
- Chemical
- Sediment
Urine turbidity
Concentrated samples in healthy animals
- cells
- protein
- mucus –seen in healthy horse
- crystals –seen in healthy rabbits and horse
- lipids
Mechanisms/ causes of Proteinuria
- Urinary Tract Hemorrhage
- Urinary Tract Inflammation
- Pre-Renal Proteinuria
- -Physiologic
- -Overflow - Primary Renal dz
- -Glomerular
- -Tubular
2 main mechanisms of Glucosuria
- Overflow = increased serum glucose
2. Decreased tubular function
Adequate Urine Concentration (define / critical cut offs)
“Minimum SG in otherwise healthy animal that NEEDS to conserve fluid”
Cat = >1.035 Dog = >1.030 others = >1.025
3 ketone bodies
- Acetone
- Acetoacetate –mainly detected
- B hydroxybuterate –mainly produced
Dz associated with Ketone formation, and why it occurs.
Due to NEGATIVE ENERGY BALANCE
- Diabetes mellitus
- Lactation
- Late Pregnancy
- Starvation
- (hepatic lipidosis)
What changes would you see in Diabetes mellitus in a UA?
Ketonuria and Glucosuria
increase serum glucose
Renal threshold for glucose (define / species values)
The concentration at which the PCT can no longer fully reabsorb glucose. Cows = 100 Horses= 150 Dogs = 180 Cats = 280
Only form of bilirubin found in urine (and why?)
only CONJUGATED bilirubin
-water soluble and NOT protein-bound –> freely filtered
Form of bilirubin detected by urine test trips
Specific for CONJUGATED bilirubin
What is the “tablet test” called/ used for?
Ictotest
- confirms presence of conjugated bilirubin
- more sensitive when urine is dark
Severe hemolysis –> bilirubinuria
Severe hemolysis –> rapid drop in Hct –> traumatic insult to liver (ALT) –> swelling –> compression of ductules and ducts –> cholestasis! –> back up of conjugated bilirubin in blood –> filtered –> bilirubinuria
Occult blood on test strips
- 3 processes and what would be detected
- Hemorrhage –> Intact RBCs
- Hemolysis –> Hb
- Rhabdomyolysis –> Myoglobin
To differentiate the 3 types of occult blood.
RBCs
- patchy chem strip
- spin –> RBCs will spin out
- examine sediment
Hb
- Check Hct and RBC morph
- pink/ red serum –due to haptoglobin
Myoglobin
- Hx &PE
- clear serum –bc freely filtered
- check muscle enzymes
pH change in stored urine
CO2 lost to environment –> alkalization
this also breaks down organic components
Bacteria –> alkaline urine
Urease producing bacteria –> increased ammonia –> alkalization
Alterations caused by alkaline pH
pH > 8
–> Trace to 1+ protein AND breakdown of organic components
Where are casts formed?
DISTAL tubules
Mucoprotein that forms cast matrix
Tamm-horsfall protein –secreted via DCT epithelium
Process for presence of EPITHELIAL casts
-Tubular degeneration (aka granular casts)
Process for presence of GRANULAR casts
-Tubular degeneration (aka epithelial casts)
Process for presence of WAXY casts
- Tubular degeneration (+/- slowed transit)
- -further degenerate than granular cast
Differentiate btwn Pyelonephritis and cystitis
Cystitis = WBCs in urine
- no systemic inflamm
Pyelonephritis = WBC or WBC casts in urine
- systemic inflamm, fever
Pigmented urine crystals
- Bilirubin –golden
- Leucine –yellow spheres
- Urates –yellow-red to yellow-brown
- Sulfa-type drugs
Healthy Dalmatian urine crystals
- Ammonium Urate / biurate (“Thornapple”)
* Uric acid crystals are a common pathologic crystal in Dalmatians
Crystals associated with Ethylene glycol
Calcium oxalate
- Monohydrate form –specific for ethylene glycol
- Dihydrate form –normal w/ plant diet (also in EG tox)
Crystals associated with Hepatic insufficiency
-ammonium urate / biurate / “thornapple”
Crystals associated with cholestasis
Bilirubin Crystals
Dumb-bell crystal
Calcium carbonate
-in healthy Lg animals
Hear the word Bilirubin-uria… THINK?
CHOLESTASIS!!!
Why is it more significant to have a small amt of protein in dilute urine (vs concentrated)?
USG is on a sliding scale, which means normal amounts of solute will be in a dilute or concentrated…
Concentrated sample is more likely to have detectable proteins, bilirubin, etc
What is hyposthenuria
<1.005
Indicates dilutional funx
What to components of urine can affect USG?
- increases USG 0.001
- High levels of ALBUMIN (3+)
- Small Amt of GLUCOSE (1+)
3 tests for Protein
- Chem strip
- SSA –sulfosalicylic acid
- UPC – urine protein: creatinine ratio
For Protein, what does chem strip detect?
Albumin mainly
**alkalinity –> falsely elevates
What is the purpose of the SSA test?
- confirm protein in alkaline urine
2. confirm presence of NON-albumin proteins
What is the purpose of UPC?
- Confirm that the degree of proteinuria is signify
2. Provide baseline value for monitoring dz progression
Interpretation of UPC >10
GN or amyloidosis
When is is appropriate to use UPC?
- When there is NOT evidence for inflammation or hemorrhage
Which comes first… Ketonemia or -uria?
Ketonuria
-freely filtered w/o reabsorption
How does storage affect bilirubin in the urine?
**Exposure to light –> neutralization of bilirubin –> false negatives!! w/in 30mins
What is the significance of detecting Nitrite?
- determines if bacteria are present by detecting product than their enzyme produces
- Nitrate –Reductase–> Nitrite
*Urine must be in bladder >4 hrs (not likely w/ UTi)
Factors associated w/ crystal formation
- Urine pH
- High USG
- Cyrstalloid solubility
- Temp –fridge promotes crystals
