urine analysis

Question 1

How should urine samples be collected to avoid contamination?

Answer 1

Place in a sterile container.

Question 2

What type of urine container is sufficient for most urinalysis?

Answer 2

Plain sterile container.

Question 3

What additives can be used in urine samples and their purposes?

Answer 3

Boric acid: bacterial culture (most common)

Toluene/Thymol: chemical examination (less common)

10% Formalin (1 drop/2.5ml urine): preserves sediments like crystals and casts

Question 4

What factors affect normal urine volume in cats and dogs?

Answer 4

Diet, exercise, breed, and disease processes.

Question 5

What is polyuria?

Answer 5

Increased urine production

Question 6

What is polydipsia?

Answer 6

Increased drinking, usually accompanies polyuria.

Question 7

What is oliguria?

Answer 7

Reduced urine production.

Question 8

What is anuria?

Answer 8

No urine production.

Question 9

What is the normal urine colour in cats and dogs?

Answer 9

Translucent, pale yellow to deep amber.

Question 10

Why can rabbit and guinea pig urine appear turbid (cloudy)?

Answer 10

Due to calcium carbonate crystals.

Question 11

What does red urine indicate?

Answer 11

Haematuria – red blood cells in urine.

Question 12

What does red-brown urine indicate?

Answer 12

Haemoglobinuria – haemoglobin from ruptured red blood cells.

Question 13

What does orange-yellow-green urine indicate?

Answer 13

Bilirubinuria – bile pigments in urine.

Question 14

Which drugs can cause abnormal urine colours?

Answer 14

Purple: Phenothiazines (ACP)

Orange: Tetracyclines (antibiotic)

Question 15

What is the normal urine production rate in cats and dogs?

Answer 15

1–2 ml/kg/hr.

Question 16

What is the normal odour of urine?

Answer 16

Characteristic sour smell.

Question 17

What does sweet, fruity-smelling urine indicate?

Answer 17

Presence of ketones.

Question 18

What does very pungent, ammonia-like urine indicate?

Answer 18

Bacterial infection or old urine with bacterial contamination.

Question 19

What does urine specific gravity (USG) measure?

Answer 19

The weight of urine compared to water; indicates urine concentration.

Question 20

What is the USG of pure water?

Answer 20

1.000

Question 21

Normal USG ranges for cats?

Answer 21

1.035 – 1.060

Question 22

Normal USG ranges for dogs?

Answer 22

1.015 – 1.045 (ideally >1.030)

Question 23

Normal USG ranges for rabbits and guinea pigs?

Answer 23

1.005 – 1.050

Question 24

How do urine test strips work?

Answer 24

Test pads contain reagents that react with urine, causing a colour change compared to a reference chart or instrument.

Question 25

How is urine applied to test strips?

Answer 25

By dunking/dipping the strip into urine or pipetting urine onto the strip.

Question 26

What are key safety and storage points for test strips?

Answer 26

Wear PPE Do not use expired or damaged strips Keep container tightly closed Store at room temperature Avoid contamination from disinfectants Follow specific timing for each test pad

Question 27

What does glucose on a test strip indicate?

Answer 27

Glycosuria – glucose in urine.

Question 28

What do ketones on a test strip indicate?

Answer 28

Ketonuria – ketones in urine.

Question 29

What does protein on a test strip indicate?

Answer 29

Proteinuria – protein in urine.

Question 30

What does blood on a test strip indicate?

Answer 30

Haematuria (RBCs) or haemoglobinuria (free haemoglobin).

Question 31

What does pH on a test strip indicate?

Answer 31

Urine acidity/alkalinity (pH 1–14, 7 neutral). Aciduria = acidic urine (low PH) Alkuria = alkaline urine ( high PH)

Question 32

What do bile pigments on a test strip indicate?

Answer 32

Bilirubinuria; normally positive in ~20% of dogs and 5% of cats.

Question 33

Why must urine sediment be examined quickly?

Answer 33

Cells and casts deteriorate, and new crystals can form, causing false results.

Question 34

How is a wet preparation of urine sediment made?

Answer 34

Centrifuge at 1500 rpm for 5 min Remove most supernatant Re-suspend sediment Pipette sediment onto slide Apply cover slip carefully Reduce microscope light intensity Examine at low and high magnification

Question 35

How can staining improve urine sediment examination?

Answer 35

Stains enhance visibility and identification of cells, casts, crystals, and bacteria.

Question 36

Name general stains used for urine sediment

Answer 36

Sedistain (Sternheimer-Malbin) – added to sediment Leishmann’s stain – general microscopy Gram stain – bacterial identification

Question 37

What is an alternative to wet prep for staining?

Answer 37

Create a smear from sediment and stain like a blood smear.

Question 38

What is the most common type of urine crystal?

Answer 38

Struvite (magnesium ammonium phosphate, triple phosphate).

Question 39

What is the typical appearance of struvite crystals?

Answer 39

Coffin lid shape.

Question 40

Can struvite crystals be normal?

Answer 40

Yes, small amounts can be seen in clinically normal cats; large quantities are abnormal.

Question 41

Which animals normally have calcium carbonate crystals?

Answer 41

Rabbits and guinea pigs

Question 42

What are the shapes of calcium carbonate crystals?

Answer 42

Dumbbell shape or circular with radial striations.

Question 43

What is the shape of cystine crystals?

Answer 43

Hexagonal; rare.

Question 44

Which breed is predisposed to ammonium urate crystals, and what do they look like?

Answer 44

Dalmatians; small spiky spheres (“thorn apple”).

Question 45

What is the appearance of calcium oxalate crystals?

Answer 45

Small square with an X in the middle.

Question 46

What is the appearance of calcium phosphate crystals and in which animals are they seen?

Answer 46

Colourless, blunt-ended needles or prisms, often in rosettes; rare, seen in dogs. Causes: Primary hyperparathyroidism, hyperadrenocorticism, idiopathic hypercalciuria.

Question 47

What is the appearance of uric acid crystals?

Answer 47

Small to medium, yellow, red-brown, or brown; polarise under light; rhomboid to diamond or flat; shape can vary.

Question 48

Which breed is associated with uric acid crystal issues?

Answer 48

Dalmatians (cannot convert uric acid for excretion); other breeds may need liver check if present.

Question 49

Which blood cells can be seen in urine?

Answer 49

Red blood cells (RBCs) and neutrophils (WBCs).

Question 50

What are squamous epithelial cells and their significance?

Answer 50

Square/angular cells, faint or no nucleus; usually contamination from genital tract during sampling.

Question 51

What are transitional epithelial cells and their origin?

Answer 51

Round cells with round nucleus; from the lining of the bladder.

Question 52

How are urine casts formed?

Answer 52

Formed in kidney tubules and washed into urine; parallel sides with rounded or broken ends.

Question 53

What are hyaline casts?

Answer 53

fragile, transparent, colourless.

Question 54

What are granular casts?

Answer 54

Most common; granules are remnants of other cells (e.g., RBCs); seen in acute nephritis and chronic renal failure.

Question 55

What are cellular casts and their types?

Answer 55

Contain RBCs, WBCs, or renal tubular epithelial cells: Epithelial cells → acute nephritis RBCs → renal haemorrhage WBCs (neutrophils) → renal tubule inflammation

Question 56

What are waxy casts?

Answer 56

Broad and angular; indicate chronic kidney disease.

Question 57

What are fatty casts?

Answer 57

Contain fat droplets; mainly seen in cats with renal disease or diabetic dogs.