Urinary System Diseases Flashcards
Define azotemia and uraemia.
Azotemia = elevation of urea +/- creatinine in the bloodstream Uraemia = the clinical signs associated with azotemia
What is pyelonephritis?
Bacterial kidney infection - may be unilateral or bilateral
What methods can we use to collect a urine sample?
Free catch
Non-absorbable cat litter
Catheterisation
Cystocentesis
What methods can we use for urinalysis?
Urine specific gravity by refractometer Dipstick analysis Microscopy Cytology Bacterial culture and sensitivity
What three places can azotemia originate?
Pre-renal - inadequate renal perfusion
Renal - reduced functional mass of kidneys due to underlying kidney disease
Post-renal - kidneys are functional but waste products are not excreted (obstruction/rupture of urinary tract)
What is the difference between acute kidney injury (AKI) and chronic kidney disease (CKD)?
AKI = acute nephron damage/dysfunction CKD = chronic nephron loss, gradual decline in renal function
What are the causes of intrinsic AKI?
Toxins
Ischaemia
Infection - leptospirosis/pyelonephritis
Cutaneous and renal glomerular vasculopathy
What clinical findings might we see with AKI?
Azotemia, uraemia - lethargic, depressed, inappetent, nauseous
An/oliguria - increased potassium leads to cardiac arrhythmias/arrest
+/- hyper/hypoperfusion
+/- other signs related to intoxication
How can we diagnose AKI from a blood sample?
Acute azotemia - increased urea/creatinine/phosphate
Increased potassium with an/oliguria
Decreased potassium with polyuria
Appropriately concentrated urine with no evidence of urinary tract obstruction/rupture
What might we expect to see on urinalysis findings?
Isosthenuric
Casts - indicate tubular injury
Crystals
Inflammatory cells or positive culture - may be pyelonephritis
How do we manage an AKI?
Remove underlying cause - gastric decontamination/adsorption
Supportive management - fluid balance, electrolytes, nutrition/nausea/pain
Specific treatment (where available)
How do we conduct initial fluid therapy for an AKI?
Crystalloids - Hartmann’s usually appropriate
Correct any hypovolaemia
Correct any dehydration
How can hyperkalaemia complicate an AKI?
Kidneys = major route of K excretion
Reduced pacemaker activity, may be bradycardic
Ventricular fibrillation, cardiac arrest
What supportive nursing care can we provide for AKI patients?
Ensure hydration, avoid overhydration - weigh regularly
Ensure renal perfusion - monitor systolic BP
Manage inappetence and nausea
Analgesia
Nutrition - assisted vs oral
What is the definition of chronic kidney disease (CKD)?
Functional and/or structural kidney disease of > 3 months duration
Irreversible and progressive kidney damage and dysfunction, usually gradual
What can cause CKD?
Chronic interstitial nephritis Glomerulonephropathy Undiagnosed/untreated infections Chronic obstructive disease Congenital Neoplastic (lymphoma)
What historical findings might we see in a CKD patient?
PUPD Weight loss Lethargy, weakness Inappetence Vomiting +/- diarrhoea +/- haematemesis/malaena \+/- signs associated with hypertension
What might we find on examination of a CKD patient?
Catabolic state, reduced body muscle condition
Dehydration
Weakness (neck ventroflexion, hypokalaemic myopathy)
Uraemic ulcers/halitosis
Hypertensive retinopathy
What are the ‘target organs’ of systemic hypertension?
Ocular (hypertensive retinopathy) - retinal oedema, haemorrhages, acute blindness
Renal
Cardiac
Neurological
What is the normal systemic BP?
120-140 mmHg.
What findings can we use to diagnose CKD?
Inappropriately concentrated urine, with azotemia SDMA = new blood test for kidney disease Anaemia Increased phosphate, decreased potassium Hypertension Renal ultrasound
How do we initially manage CKD?
Discontinue any nephrotoxic drugs
Find and treat any underlying correctible cause
Correct and maintain fluid balance
How do we manage fluid balance in CKD patients?
Encourage oral intake
Wet/slurry/soaked food
Subcut fluids
Oesophageal tube
How do we delay progression of CKD?
Renal diet
Control of hypertension, proteinuria, hyperphosphataemia, hypokalaemia
Avoid further insults
What nutrition should be provided to a CKD patient?
Must have sufficient protein calorie intake!
Renal diet
Restricted protein, phosphorous and sodium
What additional management should we provide for a CKD patient?
As determined by IRIS guidelines
Hyperphosphataemic - phosphate binders with every meal
Hypokalaemic - potassium supplementation
Manage systemic hypertension
How do we monitor progress in CKD patients?
Appetite, demeanour Body weight Blood pressure Urinalysis Urea, creatinine, phosphorous, calcium, sodium, potassium PCV
What questions should we ask to determine the history of urinary tract disorder patients?
Is your pet continent?
Can the animal void urine normally?
Does the animal urinate over the house or overnight?
Does the animal strain to urinate unproductively?
Does the animal strain to produce small amounts of urine or cry when urinating?
Does the urine smell?
Has there been blood in the urine?
Is the animal urinating more frequently?
Is the animal drinking more?
Is the animal neutered?
What are the general principles of urinary tract surgery?
Potential source of wound contamination/infection - use antibiotic cover and minimise spillage of urine
Urethral catheters may be useful intra-op
May need to provide bladder drainage post-op
What equipment might be necessary during surgery?
Fine instruments/surgical material Abdominal retractors Stay sutures/small retractors for bladder Tubes for cystotomy Urethral catheters Suction Spoons for bladder stones Magnification for ureteral surgery Sterile cotton buds
Describe renal neoplasia.
Carcinomas/lymphoma/pulmonary metastasis and bilateral neoplasia
Clinical signs include - haematuria, palpable abdominal mass, vague signs
Describe renal trauma.
May follow RTA or bite injury
Uncontrolled haemorrhage may require nephrectomy (rare)
Describe renal stones.
Often seen in animals with concurrent chronic renal failure so surgery not recommended
Many can be dissolved with diet/antibiotic therapy
Surgical removal - nephrotomy (incision through body of kidney), risk of renal reduction in renal function in the short term
Describe kidney disease secondary to ureteric disease.
Ureters at risk of trauma during spaying - removal of kidney/ureter or ureter re-implanted in some cases
Ureteral obstruction may be managed by nephrectomy
Describe ureteral ectopia.
Congenital anomaly in (female) dogs resulting in ureters opening into urethra (not bladder)
Most cases bilateral and intramural
Surgical treatment by neoureterostomy
50% of animals remain incontinent post-op
Describe bladder stones.
Struvite most common in UK
Struvite and urate uroliths can be medically dissolved, others removed by cystotomy
Prescription diets post-op to prevent reoccurrence
Clinical signs - haematuria, frequency/urgency to urinate, complete obstruction
Describe bladder neoplasia.
Common in elderly animals
Clinical signs - haematuria, frequency/urgency to urinate, obstruction
Most are malignant
Partial cystectomy for palliative care
Many affect trigone/bladder neck and cannot be excised
Describe bladder trauma.
Blunt abdominal trauma can cause bladder rupture
Can cause uroabdomen and post-renal failure
IVFT to stabilise, then surgical repair or indwelling catheter
Describe cystotomy.
Removal of bladder stones
Essential all stones removed
Stones submitted for lab analysis (for prevention treatment)
Post-op - observe carefully for absence of urination or abdominal distension
Describe management and relief of urethral stone obstruction.
Rapidly leads to post-renal azotaemia and shock
Restore circulating volume, reduce hyperkalaemia and relieve obstruction
Correct hypovolaemia, electrolyte and acid-base disturbance
Empty bladder by cystocentesis, but if allowed to become distended again can lead to urine leakage in abdomen
Careful urethral catheterisation
If unsuccessful, attempt retrograde flushing with sterile saline under GA
Once flushed back into bladder, remove via cystotomy
What are the three main types of incontinence?
Urethral Sphincter Mechanism Incontinence (USMI)
Feline Lower Urinary Tract Disease (FLUTD)
Urethral neoplasia
Describe Urethral Sphincter Mechanism Incontinence (USMI).
Most common type of incontinence (bitch spay, intrapelvic bladder)
Medically managed with oestrogen or phenylpropanolamine
Can be treated surgically - colposuspension / urethropexy / hydraulic artificial urethral sphincters
Describe Feline Lower Urinary Tract Disease (FLUTD).
Secondary to some kind of bladder disease
Leads to urethral obstruction in some male cats
Mostly medically managed to avoid need for surgery - however is an option when males suffer repeated episodes of urethral obstruction
Describe urethral neoplasia.
Rare but important in elderly bitches
Most common form is transitional cell carcinoma
Usually too advanced for surgical excision
Bypassing urethra may provide palliation in cases that are well but cannot urinate - urethral stents/tube cystostomy
Define urethrotomy.
Urethrotomy = incision into urethra
Used as a last resort for stones that cannot be flushed back into bladder (very rare)
Define and describe urethrostomy.
Urethrostomy = creation of a new urethral opening (permanent)
Used as last resort for recurrent obstruction or severe trauma or stricture
Must be made upstream from diseased urethra
Scrotal urethrostomy performed most commonly in dog, perineal urethrostomy in cat
How is a tube cystotomy carried out?
Used as urinary diversion technique - urine away from urethral surgical sites/palliation of obstruction due to neoplasia and detrusor atony
Purse string suture placed in bladder and Foley/mushroom tip catheter placed through stab incision in middle of suture
Suture is tightened
Catheter is passed through incision in lateral abdominal wall and a cystopexy is performed
Catheter is sutured to skin via a Chinese finger trap suture
Tube must be kept in place for 7 days before removal
What are the 5 main types of prostatic disease?
Benign hyperplasia (BHP) Prostatitis Abscessation Cysts Neoplasia
Describe benign hyperplasia (BHP).
Causes dyschezia / dysuria
Seen in older entire males
Managed medically with anti-androgens (e.g. Tardak)
Often castration preferred as definitive treatment
Describe prostatitis.
Bacterial infection, often together with BHP
Disease of entire males
Dysuria, pyrexia, purulent penile discharge
Managed with antibiotics and Tardak or castration
Describe abscessation of prostrate.
Usually with prostatitis in entire males
Variable systemic signs (male version of pyometra), plus dyschezia/dysuria
Omentalisation following re-roofing and flushing of abscess - also castration
Rapid surgical intervention required if abscess has burst with signs of septic peritonitis
Describe prostatic cysts.
Entire males - often associated with BHP, less commonly “paraprostatic”
Treat with de-roof and omentalisation and castration
Occasionally due to underlying neoplasia (so biopsy sent from de-roofing)
Describe prostatic neoplasia.
Disease of elderly dogs
Usually very painful
Unlike other prostate diseases, slightly more common in castrated animals
Poor prognosis - can be palliated with urethral stents if main clinical sign is inability to urinate
Define cystitis.
Cystitis = bladder inflammation.
Define pollakiuria.
Pollakiuria = increased frequency of urination
Define periuria.
Periuria = voiding in inappropriate places
What can cause cystitis?
Feline idiopathic cystitis Bacterial urinary tract infection Urolithiasis Neoplasia Drug-induced Implants/indwelling devices
What are the three main types of urinary crystals/uroliths?
Struvite
Calcium oxalate
Urate
How are uroliths formed from urine crystals?
Urine frequently saturated with compounds
Increased saturation = increased risk of precipitation, leading to crystal formation
Further supersaturation may lead to urolith formation
What are the main types of symptomatic upper urinary uroliths?
Nephroliths - abdominal pain (anorexia/inappetence, lethargy), haematuria, pyelonephritis
Ureteroliths - may cause ureteric obstruction, post-renal azotemia
More common in cats!
What are the main symptomatic lower urinary uroliths?
Urethroliths - cause obstruction, unproductive/minimally productive urination
Cystoliths - cystitis signs (pollakiuria, stranguria, dysuria, haematuria)
Uroliths may predispose UTIs
What are the nursing considerations for a patient with urolithiasis?
Vigilance - observe and monitor for un/productive urination (re-obstruction can occur at any time)
Maintain hydration/urine dilution/output
Urinary catheter care and management
Analgesia requirements
What are the signalments for feline idiopathic cystitis (FIC)?
2-7 years old Overweight, inactive Indoor, litter tray users Multi-animal household Nervous disposition Dry diet Stressors Autumn/winter
How do we rule out other causes before diagnosing feline idiopathic cystitis?
Urinalysis
Radiographs - plain, contrast and double contrast
Ultrasonography
If nothing found = FIC
How does non-obstructed FIC present?
Signs of LUTD - pollakiuria, strang/dysuria, haematuria
Still able to void
Often self-limiting
May experience recurrent episodes
How does obstructed FIC present?
Urethral spasm or plug
Unproductive attempts to urinate
More common in males, high recurrence rates (>40% within 6-12 months)
How do we care for a urinary catheter?
Closed, clean system Wear gloves for handling Keep bag off the floor Keep connections clean Change bag daily Avoid antibiotics Tape collection system to tail to avoid pulling Buster collar
What should we monitor post-catheterisation?
Urine output - ins vs outs
Hydration/volaemia status
Electrolytes
Urine sediment/cytology (infection?)
What factors can we manage to help manage FIC?
Medical management
Environmental modification
Promote urinary health
Antispasmodics
How can we modify the environment to help FIC?
Alleviate predisposing stressor
Address negative cat-cat interactions
Resource availability
Feliway
How can we promote urinary health to help FIC?
Encourage water intake
Dietary modification - wet diets/urinary diets (anti-anxiety compounds)
Avoid obesity
GAG supplementation
What are some examples of neurogenic incontinence?
Upper motor neurone lesion - spastic bladder, difficult to express
Lower motor neurone lesion - flaccid bladder, easy to express
Both lead to overflow incontinence
What are some examples of non-neurogenic incontinence?
Urethral sphincter mechanism incompetence
Anatomical defects, e.g. ectopic ureters - frequent dribbling, risk of ascending infection
Urge incontinence - detrusor instability due to bladder disease
Dyssynergia - failure of coordination of bladder contraction with urethral relaxation
How can Urethral Sphincter Mechanism Incontinence (USMI) be treated?
Alpha-agonists = sympathomimetic
Oestrogens
Urethral cuffs
Surgical repositioning of intrapelvic bladders
