General urinary Flashcards
Compare stranguria and dysuria
Stranguria - slow and painful urination
Dysuria - painful or difficult urination
What would be considered polyuric?
> 50ml/kg/day (so when measuring its 2ml/kg/hr)
What would be considered polydipsic?
Dogs - >90-100ml/kg/day
Cats - >40ml/kg/day
What is uraemia?
Clinical manifestation of urinary disease
What types of kidney cancer are considered more painful?
Sarcoma - likely painful
Lymphoma or carcinoma less so
What is azotaemia
Elevation of urea and creatinine in serum or plasma
Outline the use of urea
Affected by non renal factors - increases after feeding, with protein catabolism (sepsis/ fever), decreases with a low protein diet, liver disease, sometimes PUPD
Affected by hydration status
Best to starve for 12 hours prior to sampling
Better correlated to the signs of azotaemia than creatinine
Outline the physiology of urea
Freely filtered by the glomerus, then re-absorbed mostly in the renal tubule (this helps to concentrate u+)
Protein metabolised to ammonia - goes into the urea cycle, then goes to the kidneys to the u+
Outline the physiology of creatinine
From creatine in muscle therefore higher in well muscled animals
Some clearance from GI bacteria
Freely filtered at glomerulus but not reabsorbed, so less affected by hydration status
75% of renal function has to be gone before you see increases
Levels increase exponentially with decreasing GFR
Outline the use of creatinine
Vaules vary between labs - look for patient trends instead
Increases in haemolysed samples
better predictor of disease than urea, but less predictive of clinical signs of uraemia
Values are given for medium dogs so may vary with size
What is special with Birmans and creatinine
Have increased urea and creatinine - not all go on to develop kidney disease
Therefore important to assess other renal parameters
Always go Pre GA bloods before sx - some issues associated with neutering
What can cause pre-renal azotaemia?
Dehydration Shock Cardiac disease Recent feeding GI bleeding Increased protein catabolism
What causes renal or post renal azotaemia?
Renal - failure
Post - obstruction or rupture
How can S.G help you decide if something is renal or pre-renal
Cut off of 1.035, although need to check there aren’t other reasons for a low S.G (glucose, hypercalcaemia, addisons etc)
N.B with pre renal, urea is normally higher than creatinine
Outline the physiology of SDMA
In every nucleated cell in the body - released when there is cell breakdown
Freely filtered by the glomerulus, not protein bound
Excreted by the kidney
No muscle mass effect
Outline the use of SDMA
Useful for earlier detection of renal failure
Lower specificity than creatinine (PPV 86%, although NPV 100%)
Increases with 40% loss of renal function
Increases with dehydration, possibly also with hyperthyroidism, neoplasia and hypertension
If SDMA is very high compared to creatinine, consider IRIS staging the pet on level higher
Can be useful for proteinuric cats that are non azotaemic with a low S.G
Greyhounds appear to have higher levels in general
When is it most important to diurese IMHA cases?
When there is lots of u+ pigment - need to prevent renal damage
How long should you wait before intervening with ureteral ostruction?
1-3 days
Don’t wait if the patient is unstable
How many dogs with ureteral stones have UTIs?
59% of dogs
85% if neutrophilia present
Is it easier for uretheral stones to pass in dogs or cats?
Dogs
Cats often associated with strictures, and have a more awkward connection between ureters and bladder
What should be your main suspicion for a dog with kidney disease, liver disease, and thrombocytopaenia?
Lepto
How do you test for lepto?
Microagglutination test (MAT) Anything above 1/800 considered positive Normally don't get vaccine titres higher than 1/200
What mediteranian disease can cause kidney disease?
Leishmania
