12.7.4: Approach to haematuria and dysuria

Question 1

What could cause these colours of urine?

Answer 1

Red
* Blood
* Haemoglobin

Orange
* Strong urine
* Bilirubin

Brown
* Myoglobin
* Methaemoglobin
* Copper toxicosis
* Faeces - rectal/urinary fistula or contamination

Question 2

Diagnostic approach to red or brown urine

Answer 2

Question 3

Diagnostic approach and expected results for orange urine

Answer 3

Question 4

You centrifuge red urine. What will happen if it contains RBCs? What about if it contained haemoglobin?

Answer 4

RBCs -> will separate out
Haemoglobin -> urine will stay diffusely red when spun

Question 5

You take a blood sample and when you look at the plasma you notice it is red. Does this suggest haemoglobin, myoglobin, both, or neither?

Answer 5

• This indicate haemoglobin - haemoglobin stays in the blood longer (e.g. could be due to haemolysis.
• Compare to myoglobin which is filtered very quickly, so will not stay around long enough to make plasma red.

Question 6

Differentials and how to investigate haematuria

Answer 6

Question 7

Haemoglobinuria further diagnostics

Answer 7

• Haemoglobinuria -> likely due to haemolysis
• Investigate pre-hepatic jaundice / haemolytic diseases
• Primary haemostasis: PT, platelet count
• Secondary haemostasis: aPTT
  Neoplasia -> can lead to abnormal vessels -> abnormal epithelium may mean clotting factors are not activated appropriately

Question 8

What does myoglobinuria indicated and how could you investigate it?

Answer 8

Myoglobinuria - seen in severe muscle damage
* Seen in horses and racing greyhounds
* Physical causes: trauma, burns, strenuous exercise, prolonged immobility
* Non-physical causes: hypoxic, ischaemic, metabolic disturbances, infections

Diagnosis
* History and exam
* Biochemistry: AST, CK

Treatment
* Myoglobin is nephrotoxic -> can cause AKI -> support the patient with IVFT

Question 9

Haematuria

Answer 9

RBCs present in urine (red)

Question 10

Haemoglobinuria

Answer 10

Haemoglobin present in urine (red)

Question 11

Myoglobinuria

Answer 11

Myoglobin present in urine (red)

Question 12

Bilirubinuria

Answer 12

Bilirubin present in urine (orange)

Question 13

Dysuria

Answer 13

difficulty or pain during urination

Question 14

Stranguria

Answer 14

straining to urinate (may not produce much urine)

Question 15

Pollakiuria

Answer 15

frequent, abnormal urination

Question 16

Oliguria/ anuria

Answer 16

minimal to no urine production

Question 17

Incontinence

Answer 17

lack of control over urination

Question 18

Urge incontinence

Answer 18

very similar to pollakuria - involuntary bladder contractions voiding small amounts of urine regularly (a.k.a. ‘overactive bladder’)

Question 19

Differentials for dysuria

Answer 19

Question 20

Diagnostic approach to dysuria

Answer 20

Question 21

You see ammonium urate crystals. What should you check about the signalment and what might you be suspicious of?

Answer 21

• Is the patient a Dalmatian?
• If no, possibly a portosystemic shunt

Question 22

What history would you expect in the case of FIC?

Answer 22

FIC: feline idiopathic cystitis
* Commonly there have been environmental changes
* e.g. even just the Christmas tree going up could ause this

Question 23

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Question 24

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Question 25

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Question 26

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Question 27

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Question 28

What is hydronephrosis and what causes it?

Answer 28

Hydronephrosis: central portion of the kidney is dilated.
Caused by some degree of back pressure causing dilation e.g. post renal issue such as obstruction or pyelonephritis

Question 29

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Question 30

Pathology and next diagnostic step?

Answer 30

Chronic bladder inflammation

Question 31

Answer 31

Bladder neoplasia

Question 32

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Question 33

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Question 34

Pros and cons of exploratory laparotomy compared to endoscopy for bladder / renal pathology

Answer 34