Urinalysis

Question 1

What are the 3 types of urine sampling?

Answer 1

• Voided/free catch: should be midstream
• Catheter sampling
• Cystocentesis sampling

Question 2

Why does analysis need to be done rapidly?

Answer 2

• Cells disintegrate
• CO2 evaporates which raises pH
• Crystals form
• Bilirubin breaks down
• Bacteria grow, or die

Question 3

The following colours of urine indicate what?

• Pale yellow-amber
• Red to red brown
• Dark yellow, brown, green

Answer 3

• Normal
• Haematuria, Haemoglobinuria, myoglobinuria
• Bilirubinuria

Question 4

How can Haematuria, Haemoglobinuria and myoglobinuria be differentiated through further urinalysis?

Answer 4

Haematuria:
- red, cloudy urine
- clears on centrifuge 
- erythrocytes in sediment 
- urine red, plasma red
Haemoglobinuria and myoglobinuria:
- Red to brown urine
- doesnt clear on centrifuge
- no erythrocytes in sediment 
- urine red, plasma clear

Question 5

What is myoglobin?

Answer 5

Haem protein which transports and stores oxygen within muscles

Question 6

When is myoglobin released from muscles?

Answer 6

When there is membrane damage

Question 7

What can be the cause of cloudy urine?

Answer 7

• Mucus
• Sperm
• Lipids
• Bacteria
• Crystalluria

Question 8

How is USG determined?

Answer 8

Using a refractometer

Question 9

What is USG?

Answer 9

A measure of the total solute concentration of the urine

Reflects the kidneys concentrating ability

Question 10

Which test can be used to differentiate between renal and pre-renal azotaemia?

Answer 10

USG

Question 11

What is the normal USG?

Answer 11

• Wide variation in normal USG depending on state of hydration

Question 12

Which 3 factors can not be assessed using a dipstick?

Answer 12

• Leucocytes
• Nitrite
• USG

Question 13

What is the normal pH range for dogs and cats?

Answer 13

5-7.5

Question 14

What are the possible causes of acidic urine?

Answer 14

• Meat diet
• Metabolic or respiratory acidosis
• Protein catabolic states

Question 15

What are the causes of ketones in urine?

Answer 15

Diabetes

Negative energy balance - neonates, starvation

Question 16

What are the causes of bilirubin in urine?

Answer 16

• Haemolysis
• Liver disease
• Biliary obstruction

Question 17

How do you carry out a sediment examination?

Answer 17

• Centrifuge 1ml of urine for 3-5 mins
• Re-suspend pellet
• Place a drop on top of a glass slide and a coverslip on top

Question 18

Occasional WBCs found in urine can indicate?

Answer 18

Inflammation in the urinary tract

Question 19

What are casts?

Answer 19

Cylindrical moulds of tubules composed of mucoproteins and cells

Question 20

Which types of casts are normal and which indicate tubular damage?

Answer 20

Normal: hyaline and granular
Damage: granular, cellular, waxy

Question 21

Which crystal is made up of magnesium ammonium phosphate?

Answer 21

Struvite - forms in alkaline urine

Question 22

Give some examples of crystals that can be found in urine

Answer 22

• Calcium oxalate dihydrate
• Calcium oxalate monohydrate
• Ammonium biurate
• Cystine