Urinalysis

Dog, Cat, Sheep, Goat, and Primate Kidney Shape

Dog, Cat, Sheep, Goat, and Primate Kidney Shape

smooth, beaned-shaped

Horse Kidney Shape

Right kidney: heart-shaped

Left Kidney: flattened

Pig Kidney Shape

flattened bean-shape

Bovine Kidney Shape

lobulated appearance

Why do we conduct urinalysis in practice? (5)

• Routine Monitoring of Urinary Tract Health

• Change in physical characteristics

• known or suspected renal disease or urolithiasis

• Previous history of/suspicion of urinary tract infection

• Clinical Signs of Lower UTI (FISH)

What are the clinical signs of lower urinary tract infections?

FISH

Frequency, Incontinence, Stranguria, Hematuria

Oliguria

decreased urine production

• Very concentrated, High USG

Anuria

no urine production caused from complete shut down of the kidneys such as urethral obstruction or bladder rupture

Pollakiuria

increased frequency of urination

Polyuria

increased urine production accompanied by polydipsia

• pale or light yellow with low USG

Polydipsia

increased thirst

Stranguria

straining to urinate

Dysuria

Painful urination

Hematuria

blood in urine

Pyruria

Leukocytes in urine

Crystalluria

crystals in urine

What are the four methods of specimen collection?

• Voided

• Manual Expression

• Catheterization

• Cystocentesis

When is a voided sample preferred?

Cats

What is the best time to collect a voided sample?

First morning urine (more concentrated) and mid-stream (reduces the number of bacteria from distal urinary tract

What is the least preferred method of collection? Why?

Manual Expression

• Friable bladder - bladder rupture

• Increased blood, bacteria, and cell count

How should you choose a catheter size?

Smallest to decrease trauma but the largest to prevent leakage

What can catheterization cause to the patient?

It can drag bacteria into the urethra or bladder and cause an infection (iatrogenic)

What can catheterization do to the sample?

Increases the amount of blood, bacteria, and cell count

How much urine should you discard when collecting the sample via Catheterization?

first 1-2mL

What is the preferred collection method in dogs?

Cystocentesis

What is the most sterile method of collection?

Cystocentesis

What does a cystocentesis require?

Some volume of urine to be in the bladder

How long after collection should a urinalysis be done?

30-60 mins after collection

What color tubes have a preservative in them? What is the preservative?

Yellow or gray top tubes

• Contain Boric Acid

  • prevents bacterial overgrowth

What are the three parts of a urinalysis? What does each evaluate?

• Physical Properties / Gross

  • color, transparency, odor, foam, specific gravity, volume

• Chemical Properties

  • pH, protein, occult blood, glucose, bilirubin, ketones, leukocytes, nitrites

• Microscopic Properties

  • Sediment Analysis

Hemoglobinuria

hemoglobin in the urine due to hemolysis

Myoglobinuria

presence of myoglobin in the urine, secondary to muscle breakdown

• Common in horses with exertional rhabdomyolysis

What species have a murkier appearing urine?

horses, guinea pigs, rabbits

What species have strong smelling urine?

Bucks, Goats, Tomcats, and Boars

What does a large amount of foam that does not dissipate indicate?

increased protein

Hypersthenuria

urine is approximately concentrated

• Dogs = 1.030

• Cats = 1.035

Isosthenuria

urine has not been concentrated or diluted; SG similar to plasma

• 1.008-1.012

Hyposthenuria

urine is dilute compared with plasma

• <1.008

What three things can affect chemical properties of urine?

• Medications

• Diet

• Environmental Factors

What is the normal pH of urine in dogs and cats?

5.0-7.5

What bacteria increase the pH of urine?

Urease-producing bacteria increase pH

pH of Carnivore Urine

acidic

pH of Herbivore Urine

alkaline

What is the renal threshold for glucose?

Dogs: 180mg/dL

Cats: 280mg/dL

What are the three ketones?

Acetone

Acetoacetic Acid

b-hydroxybutyric acid

How many erythrocytes are normal per HPF?

2-3/HPF

Where are squamous epithelial cells found?

distal urethra, vulva, vagina, prepuce

Where are transitional epithelial cells found?

bladder, ureters, renal pelvis, proximal urethra

Where are renal epithelial cells found?

renal tubules

What crystals are normal in horses and bunnies?

Calcium Carbonate

What crystals are observed with ethylene glycol toxicity?

Monohydrate Calcium Oxalate

What dog breed commonly gets uric acid crystals?

Dalmatians

Pearsonema plica

bladder worm

Dictophyma Renale

kidney worm of dogs

Dirofilaria Immitis

heart worm

What specie has a large number of mucus threads?

horses

Lipuria

fat droplets in the urine