Urinary Flashcards
Indications for nephrectomy
Normal function of contralateral
Renal/ureteral neoplasia
Trauma
Persistent renal haematuria
Polynephritis - polycystic disease
End stage hydronephrosis
Chronic end stage pyelonephritis
Ectopic ureter
Contraindications for nephrectomy
Azotaemia
Persistent isosthenuria
Indications for renal biopsy
Renomegaly
Acute renal failure
Familial - renal amyloidosis, renal dysplasia, polycystic kidneys, basement membrane disorders, tubular disorders
What is a nephrotomy
Removal of renal calculi
Nephrectomy key points
Ligate vein and artery
2 ligations on ureter and divide between ligatures
Complications of renal surgery
Renal pain
Haemorrhage - haemoabdomen, haematuria
Retroperitoneal/peritoneal urine leakage
UTI
Compromised renal function
Points for removing calculi
Place stay sutures to hold bladder
Incise into ventral wall
Handle as little as possible
Close with absorbable monofilament
4/0 or 3/0 in cats and 4/0,3/0 or 2/0 in dogs
Single layer full thickness inverting or two later
Atraumatic needs
Drape omentalise
Complications of bladder surgery
Haemorrhage
Peritoneal urine leakage
Urinary tract infection
Urothelial oedema
Dysuria
Small bladder volume
Reflex dyssynergia
Indications for tube cystotomy
Functional or mechanical bladder/urethral obstruction
Excessive urine retention
Post bladder/urethral surgery
Sites of urethral obstruction
Kidney
Ureter
Bladder
Urethra
What is a SUBS
Submucosal urethral bypass system
Urethral obstruction in the dog
Dalmatians struggle with urate stones
Get stuck in caudal ospenis
Treated by retrograde urethral flushing
Cystotomy and further flushing
Neoplasms of the kidney
Most common malignant is renal carcinoma
Cystoadenocarcinomas in GSD
Benign tumours uncommon
Middle aged/older animals
Male more common
Nephroblastoma usually unilateral, can get very large
Metastatic can be unilateral or bilateral
Clinical signs of kidney neoplasms
Haematuria
Dysuria
Stranguria
Pollakiuria
May show abdominal pain, large palpable kidney, uraemia may be apparent
Bladder wall can be thickened, can palpate caudally
Diagnosis of kidney neoplasia
History
Clinical signs
Ultrasonography
Urinalysis
Radiography - excretory urogram
CT
Treatment of kidney neoplasia
Surgical removal except lymphosarcoma
Lymphosarcoma combination chemotherapy
Clinical findings for lower urinary neoplasia
Chronic obstruction to urine flow - secondary hydronephrosis
Urethral more like to cause acute obstructive uropathy
Reflex dyssynergia
Diagnosis of lower urinary tract neoplasia
History and clinical signs
Haematuria on urinalysis
Neoplastic cells in sediment
cysto/retrograde urethrogram
Categories of acute kidney injury
Haemodynamic - volume responsive
Intrinsic renal - damage to kidneys
Postrenal - urethral obstruction
What is haemodynamic AKI
Reduced renal blood supply common causes include hypovolemia, anaesthetia and use of NSAIDs
Rapidly resolved by correcting the cause, if not corrected progresses to intrinsic renal damage ischaemia and hypoxia
Intrinsic renal AKI
Renal damage caused by ischaemia, hypoxia or toxins
Ischaemia causes - hypovolemia, common following bitch spays, deep/prolonged anaesthesia, thrombosis/DIC, hyperviscosity/polycythemia, NSAIDs - normally in relation to overdose
Primary renal disease - infection, immune mediated or neoplastic
Secondary disease - infection, malignant hypertension, hepato renal syndrome, sepsis
Nephrotoxins
Post Renal AKI
Urinary obstruction - ureteral or urethral obstruction
Urinary leakage - ureteral, bladder or proximal urethra damage
Intrinsic AKI phases
1 - asymptomatic with azotaemia starting towards the end
2 - hypoxia and inflammatory responses propagating renal damage
3 - change in urine output, either improves or gets worse, lasts ~ 3 weeks
4 - recovery phase, weeks-months, can result in severe polyuria and can return to phase 1
Diagnosis of AKI
History - <1 week anorexia, V+, PUPD, lethargy, D+
Clinical exam - fluid loss, concurrent illness, specific signs - renal pain, uremic halitosis, jaundice
Biochemistry - azotaemia, hyperphosphataemia, hyperkalemia (dangerous), hypo also possible, hypocalcemia
Urinalysis - inappropriate USG, proteinuria, glucosuria
Ultrasound - POCUS, can appear normal/enlarged, peri-renal free fluid, hydronephrosis
Radiography/CT - obstructions/stones
Leptospirosis AKI
Always causes renal damage
Sometimes hepatic damage/DIC
Often leptospira pulmonary haemorrhage syndrome
Findings include thrombocytopenia, anaemia and electrolyte disturbances
Imaging - lung patterns, hepatomegaly, splenomegaly, free fluid in abdomen
SNAP for lepto
Treatment for AKIv
Underlying cause
Fluid therapy - match losses and avoid volume overload
Monitor body weight
Time!
Classification of Oliguria and anuria
Oliguria <1ml/kg/hour urine in the hydrated and perfused patient
Anuria little to no urine
Treat with diuretics but high risks of causing AKI
Renal replacement dialysis best
Peritoneal dialysis possible in first opinion
Complications of AKI
UTI - amoxy-clav first line, doxycycline for lepto
Metabolic acidosis - Hartmann’s
Tachyarrythmia - ECG, consider lidocaine
Hyperkalemia - glucose, insulin, bicarbonate
Hypertension
Nutrition - feeding tube
Prognosis for AKI
Good depending on finances and practices facility for 24/7 care
CKD presenting signs
PUPD
Anorexia
Weight loss
Dehydration
Pallor
V+/D+
Mucosal ulcers
Uraemic breath
Predispositions for CKD
Breed - dogs - westie, shar pei, bull terrier, cocker, ckcs. Cats - Persian, Abyssinian, Siamese, ragdoll, Burmese, Russian blue, Maine coon
Age - older animals but can be young with familial disease
Co-morbidities - hyperthyroidism, hypercalcemia, heart disease, peritoneal disease, cystitis, urolithiasis, diabetes
Nephrotoxic drugs
Pathophysiology of CKD
nephron loss causes other nephrons to compensate leading to increased pressure and further damage
this can lead to a uraemic crisis due to build up of normally excreted products
Diagnosis of CKD
early stage rarely picked up soon
- abnormal renal imaging, known renal insult
- persistent elevation/increasing creatine or SDMA
- persistent renal proteinuria
Later stages
- consistent clinical signs
- azotaemia, persistently elevated creatinine/SDMA
AND usg <1.035 cats or <1.030 dogs
Does not have to be isosthenuric to be at inappropriate concentrations
Treatment of CKD
treat underlying cause
recommendations around controlling proteinuria, hypotension and hyperphosphataemia
Diet is important
Later stages treating anaemia/acidosis/nausea, maintaining hydration and adequate nutrition
What is a uraemic crisis
build up of urea and other toxins usually excreted by kidneys to intolerable levels
CS - V+/nausea, anorexia, lethargy, depression, oral ulcers, melaena, anaemia, weakness, hypothermia, muscle tremors, seizures
Treatment of ureamic crisis
ivft hartmann’s
assess/treat acidosis if present
Treat nausea/GI ulceration
Nutritional support - appetite stimulants, feeding tube
Treatment of renal hypertension
ACEi - benazepril, enalapril
Angiotensin receptor blocker - telmisartan, spirolactone
Calcium channel blockers - amlodipine
Pyelonephritis
bacterial infection of the renal pelvis and parenchyma
Diagnosis - clinical signs - fever, abdo pain, PUPD. Left shift neutrophilia. Ultrasound - renal pelvis dilation , hyperechoic mucosa
Treatment - renally excreted antibiotics - amoxycillin/amoxyclav best
Renal neoplasia
commonly metastatic
benign primary - adenoma/lipoma/fibroma often incidental findings
Malignant primary - carcinoma, multicentric, lymphoma
Polycystic kidney disease
hereditary condition - fluid filled cysts from birth in the kidney, size and number increase with age
similar presentation to CRF with large irregular kidneys. Diagnosed on ultrasound.
Screen pre-breeding
Fanconi’s syndrome
disease of proximal tubules leading to reduced resorption of solutes
idiopathic/hereditary/gentamycin nephrotoxicosis
Signs - PUPD, weight loss, lethargy
Treat - remove cause
oral nacl, k+ and bicarb
Glomerular disease
can be primary or secondary
signs - CKD/uraemia
Diagnosis - haematology/biochemistry similar to crf, likely hypoproteinaemia
urinalysis - proteinuria, hyaline casts common
Indications for renal biopsy
protein losing nephropathy
AKI
mass lesions
contraindications for renal biopsy
late stage ckd
severe anaemia/azotaemia
uncontrolled hypertension/coagulopathy
severe hydronephrosis/large mass cysts
pyelonephritis/perirenal abscesses
recent NSAIDs
Nephrotic syndrome
results of protein losing nephropathies - pathognomonic for glomerular disease
CS - pitting oedema, ascites, pleural effusion, hypoalbuminaemia, hyperlipidaemia
Treatment - antiproteinurics - acei - benazepril/enalapril. anti-coagulents - aspirin/clopidogrel. fluid removal - abdominal/pleural tap, diuretics
what does iris staging allow
identification of CKD
advise treatment focussing on nutrition/hydration, control of hypertension, minimising proteinuria, controlling serum phosphate
Definition of polyuria
> 50ml/kg/day urine
definition of polydipsia
> 100ml/kg/day intake in dogs and >50ml/kg/day intake in cats
Primary polydipsia causes
altered thirst
centrally mediated disease
- neoplasia
- seocndary to osmolarity/endocrine effects
loss compensation
Physiological
- salt toxicity, exercise, high temperature
Causes of polyuria
Central diabetes insipidus
Reduced ADH sensitivity/response
Osmotic diuresis
Glucose - diabetes mellitus
sodium - post obstructive diuresis/addisons
reduced medullary/interstitial tonicity
mixed/unknown cause - crf/aki
Initial treatment for blocked bladded
pain relief
initial diagnostics for blocked bladder
potassium
acidosis
post renal azotaemia/AKI
ECG
Types of catheter for bladder
jackson tomcat - rigid with metal stylet
slippery sam - soft but no suitable adapter
Katkath - soft, adjustable length and suitable
Care with urine
must look at within 15-20 mins or crystals will form
doesn’t strongly suggest stones/not
what are struvite crystals
magnesium ammonium phosphate supersaturation of urine turns into a urolith
Struvite Uroliths in dogs
associated with UTIs
females higher tendency
40% of urinary stones
risk factors - abnormal urine retention, conditions predisposing to UTIs, lack of movement, breeds (mini schnauzer/shih tzu, bichon)
Struvite uroliths in cats
90% sterile
50% of stones in LUT
Risk factors - abnormal urine retention (not going out when its cold), formation of concentrated urine, urine alkalising metabolites in diet
calcium oxalate uroliths
poorly understood
risk factors - acidifying diet, oral calcium outside of mealtimes, excessive protein in diet
hypercalciuria - increased intestinal reabsorption of calcium/reduced renal reabsorption
hypercalcaemia - renal tubular mechanisms over whelmed
Urate uroliths
made of uric acid/sodium/ammonium urate
impaired conversion of uric acid to allantoin increases concentration in serum and urine
dalmatians/black russians are pre-disposed
associated with porto-systemic shunt
risk factors - high purine intake (offal), persistent aciduria in pre-disposed
cysteine uroliths
inborn metabolic error caused by defective tubular resorption of cysteine and amino acids
Breed - newfoundland, labradors, australian cattle dogs, mastiffs, bulldogs
Intact males
urine retention increases chances
Calcium phosphate uroliths- rare
often minor component of struvite and calcium oxalate uroliths
risk factors - excessive dietary calcium, primary hyperparathyroidism, UTI
Xanthine uroliths
impaired xanthine oxidase activity leading to hyperxanthinaemia/xanthinuria
risk factors - genetic - ckcs, acidic/concentrated urine, urine retention, allopurinol treatment
Clinical signs of urolithiasis
Lower urinary tract signs - dysuria, haematuria, pollakiuria
+/- urinary obstruction signs
Diagnosis of urolithiasis
urinalysis - not massively useful, pH good
imaging key - radiopaque uroliths - calcium oxalate, struvitem calcium phosphate. Xanthine radiolucent. Urate/cysteine variable
ultrasound sound acoustic shadowing
treatment of urolithiasis
analgesia
antibiotics - if UTI present
specific treatments and diets
surgery for calcium oxalate, calcium phosphate and large struvite
diets for uroliths
all types high moisture
all alkalinising except struvite (acidifying) and calcium phosphate
treatment of lower urinary tract neoplasia
excision most beneficial
transitional cell commonly at trigone requires reconstruction surgery
prognosis poor
urethral stenting can be useful
causes of urethral obstruction
intraluminal - plugs, uroliths, sloughed tissue
mural/extraluminal - neoplasia, strictures, anomalies, reflex dyssynergia
complications of perineal urethrocystotomy
haemorrhage
wound dehiscence
subcut urine leakage
urinary incontinence
UTO
urethral stricture
what is true urinary incontinence
patient is unaware they are leaking urine normally due to poor sphincter function
what is urge incontinence
patient is aware of the need to urinate but has a lack of control can be caused by bladder irritation
what is overflow incontinence
patient usually unaware they are urinating, urine pressure in the bladder higher than than of urethral sphincter
most common presentation of urethral sphincter mechanism incontinence
female
spayed
older
large breed
overweight
glucose related PUPD
diabetes mellitus
primary renal glycosuria
fanconi’s syndrome (basenjis) genetic
sodium related PUPD
post obstructive diuresis
high salt diet
addisons
diuretics
diagnosis of PUPD
history/signalment
clinical exam important - BCS, dehydration, neurological disease, endocrinopathic signs
USG in PUPD
> 1.030 normal hydration - nromal or polydipsia driving polyuria (or intermittent)
1.030 with dehydration - check for glucosuria, diabetes mellitus indication/fanconis
<1.030 normal hydration - primary polydipsia consideration, expect consistency
< 1.030 dehydrated - primary polyuria/intrinsic renal disease or extrinsic effects on renal function
<1.006 - diabetes insipidus/primary polydipsia, hypercalcaemia, hypoadrenocorticism. kidneys actively diluting
primary polyuria suspected
history
rule of pyometra, addisons, aki, DM, diabetic ketoacidosis, haemangiosarcoma
Triage (pocus, elecs, bg etc)
intrinsic renal disease suspected
further urinalysis
biochemistry
imaging
rnal biopsy
extrinsic renal disease suspected
further urinalysis
haematology/biochemistry
imaging
physiological assessment
azotaemia
elevated urea and creatinine
pre-renal
fluid loss and haemoconcentration
must be hypovolaemic
phosphorus likely high
rapid response to fluids
post renal
POCUS
hyperkalaemia can develop rapidly
renal disease
aki/crf
poorly concentrated but not dilute urine
phosphorus likely high
albumin and upcr - protein losing nephropathy
non-regenerative anaemia with CKD
neurogenic incontinence
cerebral - rare, loss of voluntary control, empties normally at inappropriate times
brainstem to l7 - umn bladder, absence of voluntary micturition, hard to express, increased sphincter tone, high volume of retention
S1-s3 or nerve root - lmn bladder (paralytic) - absent voluntary micturition, atonic, flaccid and easy to express, absent detrusor, can have overflow incontinence - empty for them
USMI aetiology
low urethral tone
hormonal - lack oestrogens/change in urethral structure
breeds - irish setterm doberman, bearded collie, rough collie, dalamatian
management of USMI
sympathomimetic agents - mimic storage of urine phase, rapid response, can cause restlessness, aggression,tachycardia, weightloss
Estriol - cannot use in entire, can appear in season
surgery (referral)
anatomical incontinence
intersex
ectopic ureters
detrusor instability (urge incontinence)
detrusor atony
over distension of the bladder leading to uncoordinated contraction attmeps
secondary condition
LMN disorders
detrusor atony/sphincter areflexia
causes - cauda-equina syndrome, si luxation, IVDD, tail pull, neoplasia
management - bethanecol
nursing care/manual expression , cleaning and monitoring
UMN bladder
uninhibited spincter spasticity
often paralised hind limbs
impossible to empty in early disease
later becomes automatic - empties when capacity is reached
treatment - urethral smooth muscle relaxants and skeletal muscle relaxants
monitor for UTI
idiopathic reflex dyssynergia
loss of coordination between setrusor contraction and sphincter release
cause - inflammation
can cause incomplete emptying, overstretch, atony
treatment - prevent over distension in short term, help restore detrusor contraction (parasympathomimetic agents)
commonly male large breed
non-neurogenic urinary retention
blockage
functional obstruction - urethral spasm
trauma to ureters/bladder
detrusor atony - overdistension
bladder issue treatment overview
behavioural - pheromones/psychotrophic
pain - analgesia
high urethral tone - sympatholytics (prazosin)/muscle relaxants (benzodiazepines)
Low urethral tone - alpha-adrenergic agonists (phenylpropanolamine), orstrogen analogues
detrusor dysfunction (bethanecol)
colour of myoglobinuria
brown
diagnosis for red/brown urine
dipstick - dots = blood, homogenous = myo/haemoglobin
sediment exam - RBC = precipitate cytology confirms, haemo/myoglobin = no precipitate
haemoglobin/myoglobin likely - blood sample and centrifuge - red plasma = haemoglobin, clear = test muscle markers
orange urine testing
USG - >1.040 reduces but doesnt rule out bilirubin
dipstick - -ve for RBC/Hb, +for bilirubin
blood biochem - hyperbilirubinaemia, jaundice
further diagnostics
assess for trauma
urolithiasis - sediment, ultrasound, xray
uti - urine cytology/ultrasound
inflammation
neoplasia - cbc
CBC for coagulopathy/neoplasia
AST/CK for myoglobinuria
diagnostic approach to big bladder
electrolytes/biochemistry
pocus
history
CE - pain, discharge, rectal exam
urinalysis - crystalluria, wbcs, c+s
imaging
urinary catheter to relieve pressure/can treat
cystocentesis - quick but risks rupture
normal bladder wall thickness
1.4-2.3mm dog
1.3-1.7mm cat
