Intro to Urinalysis (chem lect 3, 4) Flashcards
1
Q
MDB (Minimum Database)
A
- CBC
- Serum biohemistry
- UA
2
Q
To evaluate hydration you need a …….
A
Spec grav (specific gravity)
3
Q
These can’t be assessed without knowing hydration status
A
Relative Erythrocytosis
Relative Hyperproteinemia
4
Q
Indications for Urinalysis
A
- Clinical or biochemical evidence of urinary tract disease
- Dehydration
- Urine spec grav must be documented prior to fluid therapy to properly assess kidney function in dehydrated patients - Evidence of hemolytic disease
- Search for diagnostic crystalluria
- Liver dz
- Antifreeze (ethylene glycol poisoning)
- Drug therapy - Search for organisms in systemically infected animals
- Bacterial discospondylitis
- Systemic aspergellosis
5
Q
Before giving fluids must…
A
Get a spec grav
6
Q
Cholistasis
A
Back up of bile in the liver
7
Q
Marker for intravascular hemolysis
A
Hemaglobinemia (happens before build up in urine)
8
Q
- Liver disease causes….. in urine
- Ethylene glycol poisoning
- Sulfa drugs (TMS)
- Aspergillosis
A
- Ammonium biurate crystals
- portosystemic shunt - Calcium oxolate monohydrate crystals (only in the 3-18 hours after ingestion)
- Sulfa crystals in urine
- Bacteria secreted in urine
9
Q
Time of Day for Sample collection of urine
AM
A
AM (Fasting)
- higher USG (dec/no water intake)
- lower pH
- more formed elements (if longer period of formation)
Jen wants this to be able to evaluate concentrating ability
10
Q
Time of day for sample collection
PM
A
PM (non fasting)
- lower USG
- more alkaline pH
- possibly fewer formed elements
- if shorter period of formation
11
Q
When looking at Urine or liquid samples ……..the condenser
A
Drop down
You want it to be a little dark
12
Q
Urinalysis Procedure
A
- Evaluation of urine sediment
- Should be performed within 1 hour after collection
- Refrigeration allows prolonged storage prior to analysis
- ideally within 12 hours
- After 24 hours cells begin to lyse
- Artifacts:
- increased urine pH
- microbial proliferation
- degradation of cells and casts
- degradation of bilirubin and ketones
- Cold can falsely inc specific gravity (denser)
- Allow to warm to room temp before analysis
13
Q
3 ways to obtain urine
A
- Cystocentesis (enterocentesis)
- Transurethral catheterization
- Voided sample
- Emergency retrieval
- From floor or table (dipstick for oxidation and glucose will be innacurate)
- Never culture this
14
Q
Fanconi Syndrome
A
- Disease of proximal renal tubules of kidney
- Things pass into urine instead of being reabsorbed
- Glucose
- Amino acids
- Uric acid
- Phosphate
- Bicarbonate
15
Q
- Indication of infection in urine.
- What inhibits this …
A
- Neutraphils
- Cushings - causes PUPD
or
chem
16
Q
Cystocentesis
and contraindications
A
- Preferred method for small animals
- Avoids lower urinary tract contaminants (south of bladder)
- Contraindications
- clotting disorders
- thrombocytopenia
- Ideally collect 5-6 mL for analysis
17
Q
Technique after collection
A
- Spin down urine
- pull off liquid
- add back 1 mL and resuspend pellet (in 20 percent of volume)
18
Q
Sample Processing of urine
A
- Save 1 ml of unspun urine for chem analysis
- Do the pellet thing
- Prepare stained and unstained slide preps
- staining can introduce artifact, unstained better
- staining IS necessary if you suspect tumor cells
19
Q
Gross inspection
A
Use unspun urine for
- Color
- Clarity
Make sure container is sealed
-Ketones can evaporate (important for diabetic patients)
20
Q
Urine Color
A
- Can’t reliably asses concentration by color
- pigments in food
21
Q
Hemoglobin vs RBCs in Urine
A
If spun, RBCs pellet to the bottom of the tube.
Hemoglobin stays in soln
22
Q
Myglobin seen in ……
then do….
A
Muscle necrosis (horse tying up)
then do
AST and CK
*rarely seen in dogs
23
Q
Urine colors
- Light to medium yellow
- Colorless
- Very dark yellow
- Red to brownish-red
- Reddish-brown to brown
- Greenish tint
A
- Light to medium yellow
- normal - Colorless
- very dilute - Very dark yellow
- very concentration
- bilirubinuria - Red to brownish-red
- hematuria
- hemoglobinuria
- myoglobinuria - Reddish-brown to brown
- myoglobinuria
- hemoglobinuria
- methemoglobin - Greenish tint
- bilirubinuria
24
Q
Methemoglobinemai => Hersey syrup blood
A
Oxidative damage
- aspirin / acetaminophen ingestion
- red maple toxicity in a horse
Blood smear
- Heinz bodies
- eccentracytes
- possible anemia
- methemoglobinuria
25
Factors affecting pH of Urine
1. Carnivores and suckling herbivores: 5.5 - 7.5
2. Herbivores: 7.0 - 8.5
3. H+ excreted & HCO3- absorbed
4. Age of urine: loss of CO2 to air raises urine pH
5. Presence of contamination or pathogenic bacteria
* Urease positive bacteria: convert urea to ammonia / ammonium ion **(inc. pH)**
* Streptococcus
* Ureaplasma
* Proteus spp.
26
Postprandial alkaline tide
Inc secretion of HCl into stomach for digestion
-H sequestered in stomach making the rest of the body more alkalotic
27
Glucose
1. interpret in light of blood glucose level
2. Cats have higher renal threshold for glucose
- stress-induced transient hyperglycemia in cats
* stressed cats are insulin resistent
* stressed cats up to 250 mg/dL glucose may not be big deal
3. False negatives possible with vitamin C administration
* it's an anti-oxidant...but why it makes glucose neg. don't know
28
Ketones
1. Small organic acids
* when you break down fatty acids instead of carbohydrates
2. Most dipsticks **DON'T** detect primary ketone produced by veterinary species
* B-hydroxybutyrates
3. Most dipsticks **DO** detect acetone and acetoacetic acid
4. To eval Dz associated with **altered carbohydrate metabolism**
* Diabetes mellitus (cat DKA)
* Bovine ketosis
* Pregnancy
* **Accumulate in urine and milk before blood**
5. **NOT DETECTED IN HEALTHY ANIMALS WITH GOOD NUTRITION**
29
Carprofen physiologic effects that cause GI dz
1. Decrease mucus secretion
2. Increase acid secretion
3. Famotidine raises pH of stomach
* antacids raise pH of stomach not a good combo with a RAW diet
30
Glucosamine or flucosamine...?
1. Sugar that coats proteins
- increases with diabetes
- more reliable marker for diabetes than glucose for cats
31
Depomedrol
Pred injection
for cat asthma
32
Feeding a high fat diet dogs
1. Can give a dog pancreatitis
* dark turkey meat at Thanksgiving
2. Can cause Ketones in urine
33
Diabetes mellitus in a nutshell
1. Not making insulin or insulin resistant
=\>
2. Can't break down carbohydrates for energy
=\>
3. Forced to use fatty acids for energey
=\>
4. Makes the ketones
34
Bovine Ketosis
1. Dairy cows have insane energy requirements, break down any energy source available
2. Ketones accumulate in urine and milk before blood
35
Urine Protein Results
1+ protein in normal animal - Jen doesn't care
Interpret in context with spec grav and pH
-alkaline urine can cause false positive rxn since dipstick pad is acid-based
Common causes of proteinuria
- Urinary tract inflammation
- Hematuria
- Glomerular disease
Dipstick is VERY SUBJECTIVE
36
More accurate assessment of proteinuria
**Urine protein to creatinine ratio (UP:UC)**
We always care about protein in the urine b/c
* loss of albumin =\> oncotic pressure
* loss of antithrombin =\> hypercoagulability
37
Hemaglobinuria vs Hematuria
Hemoglobinuria =\> suspicious of intravascular hemolysis
* Remeber, Heme is a protein
Hematuria =\> would have to have a significant hemorrhage for protein in Urine
38
Positive Heme reactions
1. Intact red blood cells
2. Hemoglobin
3. Myoglobin
39
**RBCs lyse when spec grav**
**1.006**
When urine is dilute RBCs lyse
40
Heme slide:
Positive reaction
Interpret results in light of....
1. To attribute dipstick proteinuria entirely to hemorrhage, must have a 3+ heme rxn
2. Will get a positive reaction with
* Intact RBCs (will sediment when centrifuge)
* Free hemoglobin from lysed RBCs
* Free myoglobin from damaged myocytes
3. Need to interpret in light of
* Urine Collection Method (see more with cysto)
* USG (RBCs lyse when
* pH (RBCs lyse in alkaline pH)
* Plasma color
* Muscle enzymes (CK, AST)
* Ammonium sulfate precipitation can help to distinguish btwn myoglobin and hemoglobin
41
Adequate Urine Specific Gravity
| (looking on a refractometer)
Shows concentrating ability of **renal tubules**
42
Conseq. of glomerular dz
**Nephrotic syndrome**
* Pitting edema
* transudates in body cavities
* inc in cholesterol
* lipoprotein to inc oncotic pressure
* lose anti-thrombin
* hypercoagulable
43
Azotemic animal
Inc. BUN and Creatinine and high USG =\> assume dehydration
Inc. BUN and Creatinine and low USG =\> worry about renal tubules
* Look at PCV and total solids
* wants to see a relative erythrocytosis
* wants to see a relative panhyperproteinemia
44
Inadequate US
**Ability to concentrate urine compromised after 2/3 nephron mass lost**
**3/4 of nephron mast must be lost before nitrogenous waste products in urine**
* BUN
* Creatinine
Spec gravity declines before azotemia appears (this may just be cats)
45
**Isothenuria**
**USG of 1.008 - 1.012**
* Osmolality of urine same as serum
* means kidneys aren't doing jack to concentrate
* can happen when animal drinks a lot
* recheck this with an AM urine
46
**Hyposthenuria**
**Dilute urine USG**
* Kidney can dilute urine but is unable or is not concentrating urine at this time
* Psychogenic polydypsic
* Insensitivity of renal tubules to ADH
* primary ADH deficiency (central diabetes insipidus)
* Unresponsiveness of renal tubules to ADH
* hypocalcemia
* LPS endotoxemia
* ethanol :-)
47
Markers of glomerular filtration rate
BUN
Creatinine
48
90% of erythropoietin is made by.....
So cats with kidney failure expect to see.....
Kidneys
Non-regenerative, normochromic, normocytic anemia (10, 11, 12%)
49
ADH
Concentrates urine
50
Inadequate USG in cats
Glomerular dz and azotemia can precede loss of concentrating ability
* An inadequate USG in an azotemica animal is compatible with renal disease and renal azotemia **unless there are other factors that impair the ability of the kidney to concentrate including decreased hypertonicity of medullary interstitium and inhibition of ADH**
51
Cast
52
Squamous epithelial cells
* Can have nuclei in warm, moist, dark, places (places that are protected from the sun)
* Come from distal urethra
53
**Transitional Epithelial Cells**
Higher N:C ratio
line urinary bladder and proximal urethra
Stretchy
54
**Caudate epithelium cells**
only originate from renal pelvis / hilus
pyelonephritis
we probs won't see this
55
**Renal tubular epithelium**
Will probs never see
* would have spec grav in toilet
Indicates renal damage or inflammation (tubular nephritis)
Originate from renal parenchyma
56
**Hyaline casts**
Protein net that nephrons make
low number is normal
* Exercise
* Hyperthermia
Large numbers can be glomerular disease
57
Casts about:
Recorded as a number per LPF
Best visualized on unstained prep
Large number can indicate renal tubular disease (why so much protein...?)
* Granular casts: can be part of normal processes
* Hyaline casts
* Can be normal if an animal is being diuresed
* Large numbers =\> glomerular dysfunction
58
**Epithelial (cellular) casts**
Never normal: (peeing out whole renal tubule)
* acute tubular dz
* should have low spec grav
May be seen with nephritis / pyelonephritis
Will undergo degeneration to produce granular casts
NMB stained
59
**Course Granular Casts**
This has some bilirubin
Indication of renal tubular disease
Degenerates into =\> Fine granular =\> Waxy cast
60
Granular cast with Coarse =\> fine =\> waxy portions
One may not be a big deal (indication an animal hasn't peed in awhile)
* Normal spec grav
* Not on amikacin
* NBD
If animal is on amikacin: **BD**
61
Waxy casts
vs
Hyaline casts
**Waxy casts:**
Sharp edges
should have weird spec grav
**Hyaline casts:**
Smooth
Round
Columnar
62
**Fatty Cast**
Hyperlipidemia
* Diabetes mellitus
* Nephrotic syndrome
63
**Hemoglobin casts**
* Hemoglobinemia
* Red pigment in urine
* Low PCV
* Suspect intravascular hemolysis (IMHA)
Hemoglobin...can cause renal tubular damage ?!
64
**Pseudo-casts**
This is a mucus thread
Cats: mucus in urine
Change in diameter also indicates NON CAST
65
Blood Cells and bacteria
Detailed evaluation
1. Centrifuge resuspended pellet
2. Remove all of supernatant
3. Make a smear preparatio of pellet
4. Blow dry (FL) Air dry (mojave desert)
5. Diff Quik
* Aside: Diff Quik clumps chromatin =\> makes something falsly look like a lymphoblast
* makes you think something has lymphoma
* Aside: **Diff Quick good for seeing distemper inclusions**
66
UTI antibiotics
Clavamox : antiinflammatory / cystitis
Cephalexin
Give for 21 days
67
Cat cystitis
Stranguria
dysuria
Usually sterile (Jen says maybe not sterile)
68
**Lipid droplets**
* Variable size
* Green tint
* Refractile: jeweling =\> come in and out of focus
Can be confused with RBCs
69
1. Erythrocytes are all the same size, may be crenated (can look like acanthocytes if they sit in urine for a couple of minutes)
* Discoid appearance
2. Lipid droplets are variably sized, refractile spheres
* Produced by tubular epithelium
* Common in cats
* No clinical significance
3. White blood cell
70
1. Transitional Epithelium
2. Squamous epithelium
3. Neutraphil
71
**Unstained RBCs**
72
1. Unstained WBCs
2. Two RBCs bottom right hand corner of L picture
73
NMB stained WBCs (neuts)
74
Unstained Bactiuria
Abnormal from cysto
May happen in urine sits at long time at room temp
75
Air Dried Diff Quick
Tons of bacteria (thin rods)
Neutraphils?
Transitional epitelial cells probably (Big Nuclei)
76
Air dried Diff Quick
Diplococci
* These chains are **not rods**
* Go to oil to get good idea of morpology
Also probs transitional cell =\> huge nucleus
77
Crystalluria
**Crystalluria does not = urolith**
Form in Acidic urine
Can be artifact
78
Crystals that tend to form in acidic urine
1. Ammonium urate (ammonium biurates)
2. Amorphous urates
3. Bilirubin
4. Calcium oxalate mono- and dihydrate
* often artifact
5. Cystine
* Metabolic defect
6. Sulfa metabolites
* TMS
7. Uric acid
79
Crystals that form at Neutral pH
1. Ammonium urate
2. Calcium oxalate mono- and di- hydrate
* Tons in Horses: secrete a ton of Ca
3. Cystine
4. Magnesium ammonium phosphate (struvite)
80
Take home message:
1. Crystals that tend to form in acidic urine:
2. Crystals that tend to form in basic urine:
1. Acidic: Calcium oxalate dihydrate
2. Basic: struvites
81
Crystals that form in Alkaline Urine
1. Amorphous phosphates
2. Calcium carbonate
3. Magnesium ammonium phosphoate (struvite)
82
Different casts
1. Hyaline
2. Hyaline with fat
3. Hyaline to fine granular
4. Cellular
5. Cellular to coarse granular
6. Coarse granular
7. Finely granular
8. Granular to waxy
9. Waxy
83
Synonyms for struvites
1. Magnesium ammonium phosphate
2. triple phosphate
3. infection crystals
84
**Calcium carbonate crystals**
Radiating spheres of yellow brown spicules
WIll see in all horses unless horse is in renal failure
* anuric horses will be hypercalcemic
Forms in Alkaline urine
Dumbbell shapes also normal
85
**Struvites / Magnesium ammonium phosphate (MAP, Struvite)**
* Coffin lids
* Alkaline urine
* Secondary to UTI in dogs
* Sterile cystitis (cats)
3D, look for yellow green line
**Form in vitro in refrigerated, stored urine samples or samples that become alkaline with storage**
* When detected in stored sample take fresh sample to check
86
**Amorphous phosphates**
* Seen in alkaline urine
* commonly found in clinically normal animals
87
**Urates / amorphous urates**
* small brown spheroids
* seen in acidic urine
* predisposed breeds
* Dalmations
* English bulldogs
There is also a RBC / RBCs and WBC / WBCs
88
**Calcium oxalate crystals**
* See with calciuresis (cushings)
**Top: Dihydrate form**
* Envelope-shaped
* can be normal in acidic urine and horses
* ingestion of oxalate containing plants (beets, spinach, etc)
**Bottom: Monohydrate form**
* Elongated flat crystal with pointed ends
* Seen 3-18 hours post ethylene glycol poisoning
89
Calcium oxalate monohydrate crystals
Forms in acidic urine
* struvites form in basic urine
If you suspect ethylene glycol poisoning check osmalility of the blood
* HIGH osmolality = positive for E.G. poisoning
90
**Ammonium biurate**
* Thorny apples
* Severe hepatic dz
* Portovascular malformations
* **Sago palm toxicity: almost always fatal**
* **Normal to see 1 or 2 in Dalmations or English Bulldogs**
* Purine metabolism prob: can't convert uric acid to allantoin
91
**Ammonium biurate nephroliths**
* This dog has a portosystemic shunt
92
**Bilirubin crystals**
* light sensitive
* can be found in normal dog urine
* **significant in cats b/c renal threshold 9X higher than dogs**
****Disorder in bilirubin metabolism
* Liver dz (hepatic/post hepatic)
* pancreatitis
* extravascular hemolysis and intravascular hemolysis
\*bilirubin seen first in urine =\> then in blood =\> then in tissues (icterus)
93
**Cystine crystals (NEVER DISMISS)**
* can't see on rads
* colorless, falt hexagons that build on each other
* **always abnormla**
* **look for urolith (os penis-butt shot)**
Breed disposition
* male
* dachshunds
* english bulldongs
* newfoundlands
* siamese cats
* chihuahuas
* rottweilers
94
Bilirubin comes from
Extravascular hemolysis
Liver dz
95
**Sulfa crystals**
* Look like haystack bundles
* pale yellow
* happens in patients on sulfa drugs
96
**Whipworm Egg**
* Panacure is the only thing that gets rid of Whipworms
* Same density as fecosol so don't always see them
* Also intermittant shedder
Strongid doesn't kill whipworm
97
Capillaria
98
Systemic Aspergillosis
## Footnote
**In medicine if you suspect aspergillosis RUN A UA FIRST**
99
**Candida**
* Animals on systemic antibiotics
* Indwelling catheters
100
**Transitional Cell Carcinoma**
* Hard to call if there is tons of inflammation
