Lower Urinary Tract Disease Flashcards
What counts as the lower urinary tract?
- Bladder
- Urethra
- fundamental design fault
- males… ridiculously narrow
- females…. Far too short and quite wide
- Prostate
- don’t forget the possible role of the prostate in dogs with LUT signs …. but refer to repro
Define stranguria
•difficult and slow urination +/- straining
Define dysuria
•difficult +/or painful urination
Define pollakiuria
•abnormal frequent urination (“little & often”)
Define haematuria
- presence of blood in the urine
- Can be microscopic (just on dipstick or something, could we have caused it?) or macroscopic (think about when the blood seems to occur)
- Could you have caused it? (i.e. iatrogenic by cysto or catheterisation)
- small amount of blood isn’t always significant in a urine sample
Define peruria
- urination at inappropriate sites
- Can be misinterpreted as incontinence
Define anuria
- failure of urine production by the kidneys
- end stage in AKI à no renal output
- or just not able to pass urine??
Define oliguria
- significant reduction in urine production
- < 0.5 mls/kg/hour
Define polyuria
- increased urine production
- primary (eg CKD, diabetes)
- secondary (eg psychogenic polydipsia, increased drinking after exercise)
What is the difference between LUT signs and a small bladder vs a full bladder?
LUT signs and a small bladder: very uncomfortable but not usually life threatening
LUT signs and a full bladder: urethral obstruction much more likely and is life threatening –> AKI. Act as an emergency as if its not now, it will be very soon!
With dysuria, where are some anatomical sites to consider?
Is the problem in the:
- Bladder
- Urethra
- Genital tract
- prostate
- vagina
LUT signs –> Discomfort/straining –> usually bladder or urethra but don’t forget about the genital tract that might be causing straining as well
What are some things that can cause dysuria?
- Inflammation of LUT or genital tract
- Infection resulting in inflammation
- Narrowing/obstruction of the urethra
- physical e.g. stricture, mass, calculus, “plug”, blood clot (can be haemorrhage from the kidney or somewhere)
- functional e.g. urethral spasm
- Dysuria and haematuria together are strongly suggestive of LUTD
If you have haematuria, what are some anatomical sites to consider?
Where is the blood coming from? Are we focussing on the right sight?
- Renal
- trauma, neoplasia, calculi, idiopathic (in dogs, sometimes a kidney starts to bleed and we don’t always know why this is)
- Post-renal
- inflammation, infection, calculi, neoplasia, iatrogenic
- genital causes – oestrus, prostate disease
- Could be a systemic disease leading to coagulopathy –> what could be causing this?
If you have haematuria and the blood is brown, where is it likely to be from?
Does the urine look red or brown? Is it fresh? Brown – idiopathic renal haematuria
If you have haematuria and the blood is coming towards the end of urination, where might it be coming from?
Does urine colour change or is it abnormal throughout urination? Is it at the end of urination, might be from prostate? Is it early on in in urination showing might be urethral
Is haemoglobinuria or myoglobinuria more common in small animals?
Haemoglobinuria - more common
Myoglobinuria - rare in small animals
Haemoglobinuria:
- What colour is the urine sample usually?
- What happens if you spin the sample? Urine and blood
- Pre-renal causes?
- Post-renal causes?
- Pink/red urine
- Spin a urine sample: supernatant stays pink
- Spin a blood sample: plasma is often also pink
- Pre renal
- RBCs lysed in circulation e.g. IMHA
- plasma will be pink
- Post renal
- RBCs lysed in hypotonic urine
- plasma may be normal
Myoglobinuria:
- What colour is the urine sample usually?
- What happens if you spin the sample? Urine and blood
- What can cause it?
- Red/brown urine
- Spin a urine sample: supernatant stays coloured
- Spin a blood sample: plasma is clear
- Systemic disease causing extensive muscle destruction
- ischaemic necrosis
rare in small animals
Why can haematuria cause problems on dipstick analysis?
Dipstick analysis can be misreading – if red urine, can stain pads on dipstick test so can make it difficult to work out if there is anything meaningful. Dipstick may give false positives
In dogs, what are 90% of bladder tumours?
~90% of bladder tumours in dogs are transitional cell carcinomas
Are bladder tumours more common in males or females?
Is there any increase of these tumours in certain breeds?
- in females cf males
- in some breeds (Westies, Scotties, Shelties)
What is the most common bladder tumours in horses?
- SCCa is most common bladder tumour
- SCCa: squamous cell carcinoma
- sarcoids - urethra/external genital tract/sheath
How can UTIs cause dysuria secondary to other problems?
Secondary to other problems including
- systemic disease
- low urine SG
- immune compromise
- Think about cats with hyperT4, DM
- anatomic defect
- Ectopic ureter?
- Any time anatomy incorrect, bacteria take advantage of the lack of normal! If ureter attaching in different place, more susceptible to infection and don’t have normal key mechanism to prevent infection taking hold
- urinary calculi
- Causes inflammation and irritation, bacteria will start to colonise wall of bladder and cause problems
- Neoplasia
- Ulceration of mucosa –> compromised defences
- Bleeding and unhealthy tissue, bacteria will leap in on top
- It’s a secondary infection and may need to look further for the underlying causes
What are some things that are obstructions that can caue dysuria?
- M - Urinary calculi
- N - Neoplasia
- I - Urethral plugs
- T - Rupture