Urinary Flashcards
What are the seven major urinary disorders?
Protein losing nephropathies Chronic kidney disease Acute renal failure Urinary tract infection Urolithiasis Feline lower urinary tract disease Disorders of micturition
What are some major clinical signs associated with urinary tract disorders?
Discoloured urine, pollakiuria/stranguria/dysuria, polyuria/poldypsia, urinary incontinence, azotemia, uraemia, proteinuria, obstruction, calculi, infection.
Boris has been passing red urine and straining to urinate. What is causing the red discolouration?
Haemoglobinuria or haematuria.
Differentiate between pigment and red blood cells.
Why does haemoglobinuria occur?
Intravascular haemolysis.
Mostly occurs in spleen & liver.
DDx: anaemia, Zn, Cu, onions, vena caval syndrome/heartwom cause it.
Why does haematuria occur?
Evidence of urogenital tract bleeding.
DDx: genital structure bleeding, urinary tract bleeding, haemostatic disorders
What should you consider when you have haematuria?
Bleeding at beginning or end of stream?
Bleeding from prepuce or vulva not at urination?
Bleeding associated with straining or increased frequency?
RBC casts present?
Is blood in cystocentesis sample?
What does bleeding at the beginning or end during urination?
Beginning bleeding is from urethra or prostate.
End bleeding residual blood in bladder.
Taffy has blood mixed in with urine. Urine sediment exam shows red blood cell casts, few WBCs and no bacteria. There is no straining or increased urination frequency. Where is the blood coming from?
Renal casts indicate the issue is with renal tubules/kidney.
A dog is straining. What are the two reasons that caused this?
Straining from obstruction or inflammation.
What are common types of urethral obstruction?
Calculi (stones)
Mucous plugs
Neoplasia
Functional
How would you approach a patient with pollakuria/stranguria/dysuria?
Palpate bladder & do rectal. (before and after voided urine)
Cystocentesis.
Imaging?
Catheter?
2yo Lhasa Apso has 4 weeks of increased water intake, weight loss, mild inappetance and occassional urinary accidents. What’s you approach?
Take a good history first.
Blood & urine analysis.
Do USG, dipstick, glucose, Ca, creatinine, BUN.
What is the normal amount in ‘normal’ client dogs should drink?
40mL/kg/day
What is the amount of drinking in mL/kg/day indicating polydipsia?
100mL/kg/day
What do hyposthenuria, isosthenuria & hypersthenuria indiate?
Strength of urine, so osmolality in comparison to plasma.
A dog has hyposthenuria or hypersthenuria what does this tell us is working?
Kidney tubules are actively concentrating or diluting.
What urine ‘strength’ will a dog or cat in chronic renal failure have?
Isothenuria in dogs
Cats can produce concentrated urine (hypersthenuria).
What are some DDx’s you can come up with for primary polydipsia?
Psychogenic
Hypothalamic
Hyperthyroidism (feels hotter so drink more)
Hepatic insufficiency
What is required to make concentrated urine?
Renal tubule cells create osmolarity & ADH interacts with tubule cells –> anti diuresis from both factors
What substances are required in countercurrent multiplication causing antidiuresis?
Sodium, chloride urea.
So low sodium or low urea diseases you can’t make concentrated urine eg. hypoadrenocorticism low Na disease.
How does a damaged pituitary gland affect urine concentration?
ADH made is the pituitary so can’t get the same production.
Or diabetes insipidus get large volumes watery urine not enough ADH.
What is the most important component of signalling to cause anti-diuresis?
ADH fails to send signal to renal tubules.
What is the major way that diabetes insipidus causes polyuria?
Nephrogenic diabetes insipidius (acquired/secondary) - can’t respond to ADH
Compose a differential diagnosis list for primary polyuria.
Renal failure Pyelonephrtis Diabetes insipidus Pyometra Hypokalaemia Hypercalcaemia Hyperthyroidism Hepatic failure (urea made in liver) Diabetes mellitus Drugs/toxins Primary renal glucosuria
What is your approach to a PU/PD animal?
Signalment History Phys exam - always do rectal too Complete blood count Serum chemisty Urinalysis
Can then do others like culture, radiograph, creatinine, ADH response etc.
What would be your suggested diagnosis for a young animal with incontinence compared to old female animal?
Young - more likely ectopic ureters
Old - oestrogen deficiency affecting urethral sphincter
Define proteinuria.
Excessive protein in the urine.
What is overt proteinuria?
When you have dipstick detectable protein in the urine - excessive protein.
>0.3g/L.
When do you do a urine protein:creatinine ratio check and what is the normal value?
If you think dog is losing lots of protein in urine.
Normal is
How can we find creatinine ratio?
Can divide substance: creatinine ratio. Smaller the bladder the higher the concentration.
What is the most important category of proteinuria?
Glomerular - protein (mostly albumin) leaks through holes of basement membrane
Other categories are preglomerular (haemolglobin) and postglomerular (damaged renal tubules)
What are some differential diagnoses for glomerular proteinuria?
Glomerulonephritis*
Nephropathies
Amyloidosis
What is your next step if you have an animal dipstick positive to proteinuria?
Cystocentesis.
Positive cysto –> rule of artifacts & check urine sediment
Negative cysto –> check genitals
When and why do you test urine sediment?
When you get a positive proteinuria via cystocentesis.
Indicates what’s causing proteinuria.
A dog has glomerulonephritis but you have not yet diagnosed this. How would you diagnose it?
Take cystocentesis and then check urine sediment.
Will have an inactive sediment and then check protein:creatinine ratio.
Can prevent renal failure by detecting this*
What are the distinct things you look for when differentiating preglomerular, glomerular and post glomerular proteinuria?
Preglomerular - dysproteinaemia
Glomerular - Hypoalbuminaemia, hypercholestrolaemia, high UP:UC ratio, oedema, inactive urine sediment.
Post glomerular - urine sediment
What are the 2 things you think of when you have high cholestrol?
Protein losing nephropathy
Hyperthyroidism
You have a 5 yo black labrador come into the clinic with low grade epistaxis, stiffness, swollen joints, fever & anorexia. You then find mature neutrophilia, mild thrombocytopaenia, hypoalbuminaemia, polyarthritis with no bacteria and heavy proteinura. What next?
No bacteria polyarthritis can indicate immune mediated.
Would then check USG and protein:creatinine ratio.
In the black labrador case previously you find a USG of 1.014, no hyperglobulinaemia and UP:UC 15. What do you think?
USG is dilute.
Protein:creatinine ratio is very high when normal is
What is normal USG for a dog?
1.016 to 1.06
What is normal UP:UC ratio?
What can glomerular proteinuria lead to?
Nephrotic syndrome
Renal failure
What are the three things we see in cats/dogs with nephrotic syndrome?
Heavy proteinuria
Hypoalbuminaemia
Hypercholestrolaemia
What do you look for when diagnosing glomerular proteinuria?
High albumin High cholestrol High UP:UC ratio Oedema Inactive urine sediment
What are some DDx for glomerular proteinuria?
Glomerulonephritis is the main DDx.
Differentiate with renal biopsy and treat glomerulonephritis with ACE inhibitor antihypertensive drug (opens up blood flow) & underlying cause.
Why must you recheck creatinine levels after beginning treating glomerulonephritis?
Increased blood creatinine because less blood turns into urine.
Why do you give a glomerulonephritis patient a protein restricted diet?
Avoid the increase in GFR and filtration when you consume high protein.
What are some complications of glomerular proteinuria?
Chronic or acute renal failure
Hypercoagulability state
Thromboembolism
Systemic arterial hypertension
Define azotemia.
Increased urea and creatinine
Define uraemia
Clinical signs/ consequence associated with azotemia.
What is the physiology behind azotemia?
Reduced blood flow so reduced GFR leading to azotemia.
Is chronic kidney disease pre-renal, renal or post reanl in origin?
Renal azotemia.
Why is creatinine a poor indicator of kidney disease? What would you use instead?
As disease progresses creatinine is not highly altered only when disease is extremely severe get increased creatinine.
Describe the clinical signs of the following losses in kidney function:
a) 1/3rd loss
b) 2/3rds loss
c) 3/4ters loss
a) Unable to concentrate urine - dilute urine.
b) PU/PD, dilute urine
c) Azotemic
Describe how symmetric dimethylarginine can be used in to assess renal function?
Renal biomarker with blood test diagnoses PU/PD before it occurs.
Is BUN an accurate assessor of renal function?
No.
Made in the liver (affected by liver failure/dysfunction), protein foods, GI bleeding, dehydration - all of these affect it.
A 3yo Rottweiler jumped out of a 3rd floor building bruising it’s skull, fracturing it’s pelvis. It was treated with analgesics. The next day it has high PCV, high TP, high creatinine & high BUN. What do you think was wrong with the way this was handled?
No fluids were given so caused azotemia (high creatinine high BUN).
What is normal PCV and TP?
PCV 37-55
TP 75
What do you hope to achieve with treating prerenal azotemia?
Improve GFR and let them eat and drink and feel better again.
Can you improve the GFR permanently if patient has renal failure in addition to prerenal azotemia?
Can’t fix permanent kidney function but rids pre-renal component.
What do you suspect if you have prerenal azotemia present after fluid therapy?
Underestimated dehydration
Ongoing losses like diarrhoea
Have a renal or post renal azotemia as well.
*Owner is away and the cat is left in the garage. Unresponsive cat is found collapsed. A blocked urethra was diagnosed. What next?
Don’t unblock immediately.
Put on fluids & eCG. Give saline, glucose (high insulin & K), Ca (protect heart).
Correct metabolic disturbance before obstruction.
What are two common places for urethral obstruction?
Ischial arch urethra
Os penis base
*How do you differentiate clinical signs of acute and chronic renal failure?
Acute -painful enlarged kidney, high creatinine & urea, azotemia, high K, normal HCT, low urine production.
Chronic - small fibrosis kidney, PU/PD, low appetite, vomiting, low HCT, low K, high urine output.
What are you thinking if you have an enlarged chronic kidney?
Hydronephrosis
Polycystic kidney
Cancer (lymphoma)
Which is worse acute or chronic renal failure?
Acute renal failure is worse prognosis no time to improve or repair.
What is it when you can’t produce concentrated urine but the animal isn’t azotemic?
Renal insufficiency
A dog is producing concentrated urine and is azotemic. What is going on?
Animal in renal failure
Why do chronic kidney disease dogs produce more urine?
Less blood flow through nephrons.
Describe aetiology & pathogensis of chronic kidney disease.
Irreversible.
Aetiology - maybe primary glomerular disorders.
No time for compensatory hypertrophy - can’t maintain renal function.
Why would you get oral ulceration from chronic renal failure?
Ammonia - too much urea in saliva because animal will be uraemic.
What are some features of CRF?
Azotemia Hyperphosphataemia Anaemia Thrombocytopathia (don't work as well as they should)) Isosthenuria
How do we manage CRF?
Identify & treat causes (eg. hypertension) Maintain hydration P restriction * most important Protein restriction Calcitriol H2 receptor blocker Anti-emetic
Why do we treat CRF with calcitriol?
Reduces hyperparathyroidism.
Give VERY small amounts (nanograms).
What are some ways to manage systemic hypertension?
Salt restriction
ACEI
Describe bacterial UTIs.
Common in dogs get no symptoms.
Cats get it from dilute urine (no protection from concentration) or from catheter.
LUTI more common than UUTI.
Which bacteria commonly causes UTIs?
E. Coli in cats.
More mixed infection in dogs.
Are males or females more predisposed to UTIs?
Females because of shorter urethra.
How do we treat bacterial UTIs?
Cocci use Amoxicillin-Clav
Rods use TMS, Enrofloxacin
What is the bladder defended by?
Concentration
Osmolarity
Bladder emptying
Ab, Ig, pH etc.
What are some complicating features of UTIs?
Local factors like calculi
Systemic immunosuppression like hypoadrenocorticism
How do we diagnose UTIs?
Cystocentesis
Urine sediment exam (pyruia, bacteruria, rods/cocci)
Culture & sensitivity
How should we treat uncomplicated lower UTI?
Antibiotic for 14 d. but recheck sediment/culture at end of course (relapse)
11yo female Schnauzer has recurrent UTIs as diagnosed on urine sediment. What do you do?
Were the tests done cystocentesis or free catch?
Is it really bacterial?
If bacterial are antibiotics correct?
Is it relapse (old organism) or reinfection (new organism)
Upper or lower tract?
There are large white stones in the bladder. What’s the most likely cause?
Struvites
What is your approach to a patient with pollakuria and stranguria?
Physical exam before & after urine voiding. Do cystocentesis. Fresh urine microscopically Ultrasounds (radioluscent stones) Good history taking
Define periuria.
Inappropriate urination.
Differentiate crystals and uroliths.
Crystals - microscopic, NOT stones, DON’T cause clinical signs, form AFTER urine sample collection.
What are some predisposing factors to urolith formation?
High concentrated urine Retained urine Favourable urine pH Crystallisation Decreased crystallisation inhibitors
Where do most uroliths form?
Lower urinary tract - ureters, bladder & urethra
Which type of stones are most common in order? Which of these are radioopaque?
Struvite Ca oxalate Urate Cystine Struvite, Ca oxalate are radioopaque.
Which urolith type requires alkaline urine to form?
Sturivtes
All the rest are acidic/normal pH.
Struvite uroliths are formed of what substances?
Magnesium ammonium phosphate.
More in females
What are two factors that predispose to urate stone formation?
Portosystemic shunt - increase ammonium urate secretion.
Dalmatians - enzymopathy produce more uric acid.
How do you void uroliths?
Urohydropropulsion.
Catheter retrieval
Differentiate uroliths based on shape and size.
Struvites - big radioopaque >1cm pyramid size
What’s the most important mineral component of feline urethral plugs?
Struvites.
How do Staph or Proteus infections lead to struvites?
They produce urease that leaks to alkaline urine & increased phosphate & ammonia.
So the infection actually causes struvites.
How do we treat struvites?
Surgically
Treat UTI
Maintain of Hills c/d diet/equivalent.
Give long term antibiotics if you treat with diet - there is bacteria embedded in stone that gets released as stone dissolves.
What are predisposing factors to Ca oxalate urolithiasis?
Increased urinary Ca Increased urinary oxalate Decreased urinary citrate Acidic urine Being male esp. Schnauzer
How can we treat Ca oxalate uroliths?
Surgery
Avoid salty foods
Give diuretic (decrease Ca in urine)
YOU CANNOT dissolve stones.
How do urate uroliths form?
Acidic urine
Uric acid from purine metabolism converted to allantoin.
Dalmations have excessive uric acid so gets excreted in urine (defective uric acid transport).
How do we treat urate uroliths?
Remove & analyse stones Treat portosystemic shunt. Treat UTI Hills u/d diet Allopurinol reduces conversion to uric acid.
What predisposes dogs to cystine uroliths?
Daschunds.
Inherited cystine reabsorption defect.
How do we treat cystine uroliths?
Hills u/d
Oral potassium citrate (alkalises urine).
Describe feline upper urinary tract disease.
Group of conditions/diseases clumped together like cystitis, UTI, urethral plug & uroliths.
Common clinical sign is pollakuria & stranguria.
Caused by infrequent urination & high urine concentration.
Which is common uroliths in cats?
Struvites and Ca oxalate.
What is ‘big kidney little kidney’ syndrome?
Kidney stone blocks ureter causing complete obstruction of one side. This kidney then shrivels up and becomes remnant.
How would you manage FLUTD?
Dilute the urine by feeding canned food, add water to dry food, multiple water sources, springwater/fountain.
What is idiopathic sterile cystitis?
Waxing waning disease most likely treated with antibiotics gets better then worse then better and reoccurring.
How should cat bladder palpation be performed?
Don’t palpate - it will void.
Do ultrasound or cystocentesis instead.
Health overweight male cat left in garage. Cat found in lateral recumbency & palpation of bladder reveals large orange sized bladder. What’s going on?
This is due to metabolic imbalance of potassium from a urethral obstruction.
Dehydrated cat - acidic blood (lactate anaerobic shock).
Bradycardic (electrolyte disturbance).
Get high potassium from positively charged H blood.
Can’t excrete K in urine & acidic (can’t pee).
Put on fluids IV (saline) and ecG and Ca (protect heart) and glucose to drive K intracytoplasmically.
Unblock urethra - blowing obstruction up.
Why do you get hyperkalaemia with urethral obstruction?
Blocked urethra - can’t excrete the K.
Usually accompanied with dehydration - get H going into blood & K going out.
What would you think of when you feel an orange shaped bladder compared with pear shaped water balloon bladder?
Orange - urethral obstruction
Pear - bladder & muscles are tight
What do owners commonly mistake incontinence for?
Vulvar discharge
Pollakiuria (lots of voiding)
Diarrhoea
What is the most common cause of urinary incompetence in speyed females?
Urethral sphincter incompetence
Explain the nervous innervation of the bladder.
Somatic pudendal n.- voluntary stopping urination (alpha)
Parasympathetic pelvic n - maintain homeostasis (voiding) by bladder contraction
Sympathetic hypogastric n - storage of urine (beta)
Or alpha - tightens bladder sphincter & beta - relaxes bladder to store urine.
List what the beta, alpha & cholinergic receptors are doing when storage of urine is occuring.
Beta (relax) - on
Alpha (constrict) - on
Cholinergic (contraction) - off
List beta, alpha & cholinergic receptors are doing when voiding urine.
Beta (relax) - off
Alpha (constrict) - off
Cholinergic (contraction) - on
What drug would you use to cause voiding of urine?
Bethanechol (cholinergic)
What drug would you use to relax sphincter?
Phenoxybenzamine or diazepam
How would you treat urethral sphincter incompetence in bitch?**
Phenylpropanolamine (Alpha-adrenergic agonist)
Oestriol hormone
What is it and where is the most common location for cancer of urinary system?
Transitional cell carcinoma.
Found at bladder neck.
Do a positive contrast cystogram, traumatic catheterisation.
Treat with peroxicam.
List some common prostate diseases.
Bacterial prostatitis Benign hyperplasia Prostate abscesses Cysts Neoplasia
What is the common theme in terms of species and age with prostate issues?
Middle age/older entact male dogs
Prostate is the only accessory sex gland of the dog makes up 97% seminal volume.
What are clinical signs of prostate issues?
Penile discharge Haematuria Flattened faeces Stiff gait Urethral obstruction? Fever, sepsis?
How do you diagnose prostate conditions?
Always do rectal - size, shape, symmetry, pain.
Prostatitis = painful
Hyperplasia = not painful
Do imaging & ultrasound look for mineralisation
Why don’t you perform FNA on suspected carcinomas?
As you pull needle out you can track carcinoma cells out and cause metastasis.
What is benign prostatic hyperplasia and how would you treat it?
Common from hormones.
Prostate is very enlarged (size of bladder) and non-painful.
Treat with castration.
What is acute bacterial prostatitis?
Painful prostate from ascending infection mostly E. Coli or Staph.
Get depression, fever, vomiting, anorexia.
Diagnose with US, FNA, cysto culture.
Treat w/ specific antimicrobials like enrofloxacin or TMPS.
How do you get prostate abscesses?
Complication of bacterial prostatitis.
Treat with omentalization to drain.
Differentiate lower UTI and upper UTI.
Lower - straining, discoloured urine, inappropriate urination, dysuria, pollakuria
Upper - hidden, tucked up, fever, PU/PD
What are you looking for when diagnosing UTI?
Pyuria (white cells)
Clinically how can you differentiate lower UTI and pyelonephritis?
Granular casts - indicate pyelonephritis that kidney/tubules is affected.
6yo male cat with oedema legs, abdomen & thorax. Radiography revealed thoracic & abdominal effusion. The ascites fluid revealed TP 1.5g/L. What are the DDx’s and how can we confirm and treat this?
Low protein fluid - transudate.
DDx: Cardiac disease, liver issues (leaking lymph?), glomerulonephritis.
Glomerulonephritis most likely - diagnose by urinalysis, bloods, UP:UC.
Treat with ACEI & underlying cause.
How do you perform cystocentesis - be specific?
Anaesthetise/sedate animal.
Ventral to pubic symphysis caudo-dorsal needle placement.
1.5 inch 21G needle.
7yo Siamese cat is drinking excessively. What is considered excessive? What is major cause polydipsia in cats?
100mL/kg/day = excessive intake. Normal is 40mL/kg/day.
Chronic kidney disease, hyperthyroidism & diabetes mellitus most common polydipsia cause in cats
What are the most common causes of polydipsia in cats?
Chronic kidney disease
Hyperthyroidism
Diabetes mellitus
How do you perform urine sediment microscopy and what is considered normal/abnormal findings?
Cystocentesis sample.
Normal see epithelial cells, RBC, lymphocytes.
Abnormal see neutrophils.
Cat signs of urethral obstruction. The obstruction was easily removed but the cat is still showing signs of dysuria urinating in spurts. What is the most likely cause?
Functional obstruction maybe urethral spasms explain the spurting urine.
Use phenoxybenzamine as an antispasm drug.
8yo cat ate antifreeze. What are the consequences?
Causes tubular necrosis & acidosis from oxalate & acid production.
Get Ca oxalate crystals decreased absorption, increased excretion.
Fix with IV ethanol & fluid therapy & Na bicarbonate (for acidosis)
A positive contrast cystogram was done revealing feline idiopathic cystitis. What would you do now?
Increase water intake - wet food etc.
Promote urination
Amytriptolene.
What is ‘normal’ kidney size approximately in cat?
Around 3 cm
What is some causes of kidney enlargement?
Hydronephrosis Amyloidosis Pyelonephritis Lymphoma Feline infectious peritoninitis (pyogranulomas).
What’s hypokalamic polymyopathy?
Severe muscle weakness when you are excreting lots of K not absorbing any can’t lift their head.
