Urinalysis

Question 1

What are you looking at during gross urine examination?

Answer 1

Volume, turbidity and colour

Question 2

What is the colour difference between blood and haemoglobin in urine?

Answer 2

Blood = red/cloudy
Haemoglobin = red/brown

Question 3

What should you always interpret USG alongside?

Answer 3

Hydration status

Question 4

Q
What time of day is best to collect urine for analysis?

Answer 4

Morning - urine is most concentrated (need multiple morning samples to accurately find abnormalities)

Question 5

Which USG results count as hyposthenuria?

Answer 5

<1.008 - kidneys are actively diluting

Question 6

Name as many differentials for hyposthenuria as you can

Answer 6

Hyperadrenocorticism (decreased ADH)
Hypercalcaemia (decreased ADH and NaCl reabsorption)
Hepatic disease (decreased urea)
Pyelonephritis (decreased ADH sensitivity)
Diabetes insipidus (decreased ADH)
Pyometra (decreased ADH sensitivity)
Hyperthyroidism (increased GFR)
Psychogenic polydipsia
IV fluids
Diuretics
Normal depending on hydration

Question 7

What USG readings will you see with renal disease?

Answer 7

Isosthenuria - 1.008-1.013

Question 8

Is a USG of 1.020 appropriate in a dehydrated dog?

Answer 8

No - this is minimally concentrated urine (1.014-1.029 USG)

Question 9

In what 3 situations is a USG of over 1.030 seen?

Answer 9

Dehydration
Normal
Acute kidney injury

Question 10

Which disease results in a USG of 1.014-1.029 due to decreased aldosterone?

Answer 10

Hypoadrenocorticism - decreased aldosterone results in decreased NaCl reabsorption = minimally concentrated urine

Question 11

What USG range would you expect to see in diabetes mellitus?

Answer 11

1.014-1.028 minimally concentrated urine

Question 12

Which conditions result in an increased urine pH?

Answer 12

Alkalosis
Urinary tract infection
Urinary retention

Question 13

Which 5 conditions result in acidic urine?

Answer 13

Fever
Starvation
High-protein diet
Acidosis
Excessive muscular activity

Question 14

Is a small amount of protein in urine ever ok?

Answer 14

Yes, if in concentrated urine (1+ with >1.030 or 2+ >1.040)

Question 15

What are the 4 broad causes of proteinuria?

Answer 15

Haemorrhage
Urinary tract inflammation
Kidney disease
Pre-renal proteinuria

Question 16

If a cat has a blood glucose of 17mmol/L, will glucose be seen in the urine?

Answer 16

Yes - glucose present in urine if it exceeds the renal reabsorption capacity, which is >15mmol/L in cats

Question 17

If a dog has a blood glucose of 8mmol/L, will it have glucose in it’s urine?

Answer 17

No - glucose present in urine if it exceeds the renal reabsorption capacity, which is >10mmol/L in dogs

Question 18

In which syndrome do you see glucosuria without hyperglycaemia?

Answer 18

Fanconi Syndrome - due to renal tubular pathology

Question 19

Is glucosuria seen in hyper or hypoadrenocorticism?

Answer 19

Hyperadrenocorticism

Question 20

What do the following conditions have in common?
- Starvation/Anorexia
- High-fat diet
- Diabetes mellitus/Ketoacidosis
- Very young animals

Answer 20

Ketonuria - see this before ketonaemia

Question 21

True or False?
Hyperbilirubinaemia is seen before bilirubinuria

Answer 21

False - bilirubinuria is seen first
Small amount of bilirubin in concentrated urine is ok in dogs, but even trace amounts are significant in cats

Question 22

What are the 2 main causes of bilirubinuria?

Answer 22

Hepatobiliary disease - cholestatsis or hepatic disease
Haemolysis - haemolytic anaemia

Question 23

How long can urine be stored for before testing?

Answer 23

Refrigerated for up to 12 hours

Question 24

Which method of urine sampling is best for urinalysis?

Answer 24

Cystocentesis

Question 25

How can you differentiate for certain between blood, myoglobin and haemoglobin in the urine?

Answer 25

Centrifuge

Haematuria = red blood cell pellet with clear supernate
Haemoglobinuria = no red blood cell pellet, red/brown supernate and serum shows haemolysis and anaemia
Myoglobinuria = no red blood cell pellet, red/brown supernate and serum is clear with no anaemia

Question 26

What process is useful for sediment examination?

Answer 26

Slow centrifugation over a longer period of time

Question 27

How can you rule out bacterial infection from urinalysis?

Answer 27

Culture - lack of haematuria, pyuria or proteinuria doesn’t rule out infection

Question 28

Are urine casts increased or decreased in acidic urine?

Answer 28

Increased
Decreased in alkaline urine as dissolve

Question 29

How does urine pH, concentration and temperature affect urinary crystals?

Answer 29

Changes the type of urinary casts produced

Struvite, monohydrate, calcium oxalate, dihydrate, ammonium biurate, urate and cysteine casts

Question 30

Give the 5 differentials for physiologic/benign proteinuria

Answer 30

Exercise
Seizuring
Fever
Extreme temperatuew
Stress

UP/C normally <0.5

Question 31

Is congestive heart failure a differential for pre-renal, renal or post-renal proteinuria?

Answer 31

Pre-renal

Question 32

Do parenchymal inflammation and tubular/glomerular proteinuria result in pre-renal, renal or post-renal proteinuria?

Answer 32

Renal

Question 33

Give the 2 main differentials for post-renal proteinuria

Answer 33

Urinary tract inflammation - infection, neoplasia, crystals
Genital tract inflammation - infection, neoplasia, bleeding