Urinalysis

Question 1

Physical examination of urine

Answer 1

Colour- haemoglobin, blood, myoglobin, dietary or medication metabolites
Turbidity- pyuria, lipiduria, blood, crystals (esp. horses)
Odour- urease bacteria, ketonuria

Question 2

Significance fo urine pH

Answer 2

Generally reflects body acid-base status
- except paradoxic aciduria in metabolic alkalosis of vomiting or gastric/Abomasal torsion/obstruction
May be influenced by diet
Helps interpret other results

Question 3

How does pH help interpret other results

Answer 3

very alkaline urine may yield false positive protein
Identifiable solubility characteristics of crystals may influence whether you will see them

Question 4

What does USG measire

Answer 4

urine osmolality

Question 5

Effect of non-typical soluted on USG

Answer 5

Give us a false impression of USG
e.g. in proteinuria or myoglobinuria etc.

Question 6

At what % of nephron loss is concentrating ability affected

Answer 6

60-70%

Question 7

What to interpret USG with

Answer 7

Needs correlation with hydration state and/or azotaemia

Question 8

how does proteinuria occur

Answer 8

failure of kidneys to resorb all protein

Question 9

Important consideration in interpreting urine protein

Answer 9

Think about daily urine output
If animal is polyuric (dilute urine), low protein could still be large loss over the day

Question 10

Pre-glomerular proteinuria

Answer 10

A condition that results in unusually high concentrations of small proteins in the blood means kidneys can not resorb all of it

Question 11

Glomerular proteinuria

Answer 11

Basement membrane barrier has failed due to inflammation, immune attack, accumulation of content (e.g. amyloid, immune complexes) which disrupts its architecture
can also be caused by diabetes, hypertension and kidney disease

Question 12

Tubular cause of proteinuria

Answer 12

Damaged tubular cells are not able to resorb filtrate protein as well as they should

Question 13

Which type of proteinuria cuases blood albumin concentrations to fall and ‘nephrotic syndrome’

Answer 13

Glomerular proteinuria

Question 14

Why does high urine glucose occur

Answer 14

Hyperglycaemia above renal threshold- stress, diabetes, PPID
Tubular failure (renal tubular acidosis) - if without hyperglycaemia

Question 15

What causes ketones in urine

Answer 15

Negative energy balance
Diabetic ketoacidosis

Question 16

What causes bilirubin in blood (bilirubinuria)

Answer 16

haemolysis, hepatic dysfunction
biliirubinuria may precede bilirubinaemia
less significant in dogs than cats

Question 17

Significance of leukocytes in urine

Answer 17

Not generally reliable in dogs and cats
May correlate with bactiuria in dogs (specific but not sensitive)

Question 18

Significance of casts in urine (cyclinduria)

Answer 18

Should not be any
Suggests tubule disease/damage

Question 19

What are casts seen in urine

Answer 19

protein/cell collections moulded in lumen of tubules are deposited into urine

Question 20

What does cellular csts indicate

Answer 20

Disease proces in tubules

Question 21

What do granular casts indicate

Answer 21

Will be fine/coarse
Degenerate cellular casts- implies longer stasis
Precipiated protein
Degenerate epithelial cells

Question 22

Why might myoglobin be present in urine

Answer 22

The presence of myoglobin in a dog’s urine can be a sign of muscle damage or injury. Myoglobin is a protein that is found in muscle tissue and is responsible for storing oxygen. When muscle cells are damaged or injured, myoglobin is released into the bloodstream and can be filtered by the kidneys and excreted in the urine.

The most common cause of myoglobinuria in dogs is exertional rhabdomyolysis, which is a condition that occurs when there is severe muscle damage due to strenuous exercise or activity. Other possible causes of myoglobinuria in dogs include trauma, inflammation, toxins, infections, and certain genetic disorders.

Question 23

possible conditions leading to hyperproetinaemia

Answer 23

Dehydration: When an animal is dehydrated, the concentration of proteins in the blood can become elevated. This is because the volume of fluid in the blood is reduced, leading to a higher concentration of proteins.

Inflammation: Inflammation caused by infections, injuries, or chronic diseases can cause an increase in blood protein levels. This is because the liver produces more proteins, such as C-reactive protein, to help fight the inflammation.

Kidney disease: In animals with kidney disease, the kidneys may not be able to filter out waste products and excess proteins from the blood. This can lead to an accumulation of proteins in the blood.

Liver disease: The liver plays a key role in producing many of the proteins found in the blood. If the liver is damaged or diseased, it may not be able to produce enough proteins or may produce abnormal proteins, leading to an increase in blood protein levels.

Cancer: Certain types of cancer, such as multiple myeloma, can cause an increase in blood protein levels. This is because cancer cells can produce abnormal proteins, known as monoclonal gammopathies.