12.7.4: Approach to haematuria and dysuria Flashcards
What could cause these colours of urine?
Red
* Blood
* Haemoglobin
Orange
* Strong urine
* Bilirubin
Brown
* Myoglobin
* Methaemoglobin
* Copper toxicosis
* Faeces - rectal/urinary fistula or contamination
Diagnostic approach to red or brown urine
Diagnostic approach and expected results for orange urine
You centrifuge red urine. What will happen if it contains RBCs? What about if it contained haemoglobin?
RBCs -> will separate out
Haemoglobin -> urine will stay diffusely red when spun
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?
- 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.
Differentials and how to investigate haematuria
Haemoglobinuria further diagnostics
- 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
What does myoglobinuria indicated and how could you investigate it?
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
Haematuria
RBCs present in urine (red)
Haemoglobinuria
Haemoglobin present in urine (red)
Myoglobinuria
Myoglobin present in urine (red)
Bilirubinuria
Bilirubin present in urine (orange)
Dysuria
difficulty or pain during urination
Stranguria
straining to urinate (may not produce much urine)
Pollakiuria
frequent, abnormal urination
Oliguria/ anuria
minimal to no urine production
Incontinence
lack of control over urination
Urge incontinence
very similar to pollakuria - involuntary bladder contractions voiding small amounts of urine regularly (a.k.a. ‘overactive bladder’)
Differentials for dysuria
Diagnostic approach to dysuria
You see ammonium urate crystals. What should you check about the signalment and what might you be suspicious of?
- Is the patient a Dalmatian?
- If no, possibly a portosystemic shunt
What history would you expect in the case of FIC?
FIC: feline idiopathic cystitis
* Commonly there have been environmental changes
* e.g. even just the Christmas tree going up could ause this
What is hydronephrosis and what causes it?
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
Pathology and next diagnostic step?
Chronic bladder inflammation
Bladder neoplasia
Pros and cons of exploratory laparotomy compared to endoscopy for bladder / renal pathology
