PATHOLOGY - Lower Urinary Tract Disease Flashcards
What is gross/macroscopic haematuria?
Gross/macroscopic haematuria is where there is sufficient enough blood in the urine that it can be seen macroscopically. The urine will typically appear red to brownish
What is occlut/microscopic haematuria?
Occult/microscopic haematuia is where there are erythrocytes in the urine but they cannot be visualised macroscopically
What is pseudohaematuria?
Pseudohaematuria is where the urine appears red to brownish but there are no erythrocytes present in the urine
What can cause pseudohaematuria?
Haemaglobinuria
Myoglobinuria
How can you differentiate between true haematuria and pseudohaematuria?
Urine sediment examination - erythrocytes will be visible if there is true haematuria but they will not be visible if it is pseudohaematuria
Centrifuge the urine - the erythrocytes will seperate from the urine if it is true haematuria but they will not if it is pseudohaematuria
What are the generalised causes of haematuria?
Systemic disease
Renal/ureteral disease
Bladder/urethral disease
Genital tract
Which history questions can be useful to determine if haematuria is systemic or urogenital?
Has there been bleeding at other sites?
Has there been any recent trauma?
Has there been any exposure to anticoagulant rodenticides?
When does the bleeding start during urination?
Describe the appearance of the urine?
Which factors should you be aware of on clinical examination which could help to determine if haematuria is systemic or urogenital?
Determine if there are any other sites of haemorrhage
Determine if there are any signs of anaemia
Rectal examination
Palpate the kidneys
Palpate the muscles
What are the distinguishing factors of haematuria due to systemic disease?
Haematuria due to systemic disease typically presents with bleeding elsewhere and there is unlikely to be signs of a lower urinary tract disease
What are the systemic causes of haematuria?
Primary haemostasis
Secondary haemostasis
Tertiary haemostasis
What are the distinguishing features of haematuria due to renal/ureteral disease?
Bleeding can occur throughout urination, at the end of urination or intermittently
Typically there will be no signs of lower urinary tract disease
May be concurrent haemaglobinuria
Why can there be concurrent haemaglobinuria with haematuria due to renal/ureteral disease?
Renal/ureteral disease can decrease the concentrating abilities of the kidneys resulting in the production of dilute urine. Erythrocytes within dilute urine can be lysed due to osmosis resulting in haemaglobinuria
What are some of the causes of renal/ureteral haematuria?
Pyelonephritis
Neoplasia
Caliculi
Trauma
Infarction
Cysts
Glomerulonephritis
Idiopathic renal haematuria
What are the distinguishing features of haematuria due to bladder/urethral disease?
Bleeding can occur throughout urination or at the start of urination
Signs of lower urinary tract disease
What are some of the causes of bladder/urethral haematuria?
Cystitis
Neoplasia
Polyps
Caliculi
Trauma
Cyclophosphamide administration
Feline idiopathic cystitis
What are the distinguishing features of haematuria due to genital disease?
Bleeding can occur throughout urination, at the start of urination or be unrelated to urination
May or may not have signs of lower urinary tract disease
What are some of the causes of genital haematuria?
Prostatic disease
Oestrus
Infection
Neoplasia
Trauma
What are some of the diagnostic tests which can be done to investigate haematuria?
Haematology
Biochemistry
Urinalysis
Coagulation profile
Diagnostic imaging
Cystoscopy
Vaginoscopy
Vaginal cytology
Prostatic wash
What are the key clinical signs of lower urinary tract disease?
Dysuria
Stranguria
Pollakiuria
What is dysuria?
Dysuria is difficult and/or painful urination
What is stranguria?
Stranguria is slow and painful urination or straining to urinate
What is pollakuria?
Pollakuria is the abnormally frequent passage small volumes of urine
What are the two general mechanisms of dysuria?
Mucosal irritation or inflammation of the lower urinary tract Narrowing or obstruction of the urethra or bladder neck
What are the differential diagnoses for dysuria involving the bladder?
Cystitis
Neoplasia
Polyp
Bladder rupture
Reflex dyssynergia
What are the differential diagnoses for dysuria involving the urethra?
Bladder urethritis
Granulomatous urethritis
Urethral caliculi
Urethral plugs (in cats)
Urethral stricture
Neoplasia
Urethral rupture
Reflex dyssynergia
What are the differential diagnoses for dysuria involving the prostate?
Benign prostatic hyperplasia
Prostatitis
Prostatic abscess
Prostatic cyst
Neoplasia
What are the differential diagnoses for dysuria involving the penis, prepuce or vagina?
Neoplasia
Which history questions are useful to ask when investigating patients with dysuria?
Are they passing any urine?
How much urine is being passed?
How often is urine being passed?
Is the patient painful on urination?
Describe the appearance of the urine?
Where is the animal urinating?
Is the patient licking their penis or vulva?
Has this happened before?
How long has this been going on for?
Has there been any recent trauma?
Which factors should you assess carefully on clinical examination in patients with dysuria?
Abdominal palpation
Bladder palpation
Rectal examination
Examination of the perineum and external genitalia
If possible, watch the animal urinate and take a sample
What are some of the diagnostic tests which can be done to investigate dysuria?
Haematology
Biochemistry
Urinalysis
Coagulation profile
Diagnostic imaging
Cystoscopy
Vaginoscopy
Vaginal cytology
Prostatic wash
Describe the physiological mechanism of urine storage
The sympathetic nervous system stimulates the hypogastric nerve to relax the detrusor muscle via β2 receptors and contract the internal urethral sphincter via α1 receptors
Describe the physiological mechanism of micturition
The parasympathetic nervous system stimulates the pelvic nerve to contract the detrusor muscle via M3 receptors and relax the internal urethral sphincter via the M2 receptors, allowing for the voiding of the bladder
What is the role of the pudendal nerve in micturition?
The pudendal nerve mediates the external urethral sphincter which is made up of skeletal muscle and is thus mediated under voluntary control
What are the potential causes of urinary retention?
Obstruction
Detrusor atony
Failure of relaxation of the internal urethral sphincter
Reflex dyssynergia
How do you approach investigation of causes of urinary retention?
History and clinical signs
Clinical examination
Neurological examination
Diagnostic imaging
What is detrusor atony?
Detrusor atony is where there is a loss of detrusor muscle tone resulting in incomplete bladder emptying or urinary storage
What are some of the causes of primary detrusor atony?
Primary detrusor atony is rare
Dysautonomia
Lower motor neurone disease between S1 to S3 (where the pelvic nerve arises)
What causes secondary detrusor atony?
Secondary detrusor atony is more common than primary
Secondary detrusor atony is due to chronic overstetching of the bladder
What are the key clinical signs of secondary detrusor atony?
Weak or absent urinary stream
Distended, flaccid bladder on palpation
How do you treat detrusor atony?
Bethanecol
Place an indwelling urinary catheter to rest the detrusor
What is reflex dyssynergia?
Reflex dyssynergia is where there is a loss of coordination between the detrusor muscle and the urethral sphincters resulting in delayed bladder emptying or urinary retention
What is the main cause of reflex dyssynergia?
Reflex dyssynergia is idiopathic
Which signalement is more prone to reflex dyssynergia?
Middle aged, large breed dogs
Which dog breed is particularly prone to reflex dyssynergia?
Labradors
What are the key clinical signs of reflex dyssynergia?
Urine stream intiated by not maintained
Difficult to manually express the bladder
What can reflex dyssynergia progress to?
Reflex dyssynergia can eventually cause detrusor atony
How do you diagnose reflex dyssynergia?
Reflex dyssynergia is a diagnosis based on the exclusion of all other causes of these clinical signs
What are the aims of treatment for reflex dyssynergia?
Decrease internal urethral sphincter tone
Decrease external urethral sphincter tone
Increase detrusor contraction
Which drugs can be used to decrease internal urethral sphincter tone?
Prazosin
Phenoxybenzamine
Which drugs can be used to decrease external urethral sphincter tone?
Diazepam
Dantrolene
Which drug can be used to increase detrusor contraction?
Bethanecol
What are the potential causes of urinary incontinence?
Decreased detrusor compliance
Urethral sphincter mechanism incontinence (USMI)
Overflow incontinence
Ectopic ureters
How do you approach investigation of causes of urinary incontinence?
History and clinical signs
Clinical examination
Neurological examination
Urinalysis
Diagnostic imaging
Which conditions can be commonly mistaken as urinary incontinence by owners?
Polyuria
Pollakuria
Periuria
What is periuria?
Periuria is urinating in inappropriate places
Which history questions are beneficial to ask to determine if an animal is truly urinary incontinent?
At what age did the incontinence begin?
When does the owner percieve the animal to be incontinent?
Are the able to urinate normally?
How aware are the pets of this incontinence?
What are the key signs of true urinary incontinence?
Urinary incontinence at rest
Normal urination outside of incontinence
Animal unaware of incontinence
Why is it important to do urine culture and sensitivity on patients with urinary incontinence?
It is important to do a urine culture and sensitivity on patients with urinary incontinence as there are at an increased risk of a lower urinary tract infection due to being regularly covered in urine
(T/F) Urethral sphincter mechanism incontinence (USMI) is more commonly congenital than acquired
FALSE. Urinary sphincter mechanism incontinence (USMI) is more commonly acquired
Which signalement typically presents with urethral sphincter mechanism incontinence (USMI)?
Female dogs within three years of being spayed
How does spaying cause urethral sphincter mechanism incontinence (USMI)?
Spaying causes a reduction in oestrogen which results in downregulation of the α1 adrenergic receptors at the internal urethral sphincter, resulting in decreased sphincter tone and urinary incontinence
What are some of the other causes of acquired urethral sphincter mechanism incontinence (USMI)?
Decreased urethral sphincter tone
Decreased number or responsiveness of α1 receptors
Changes in periurethral tissues
Obesity
Abnormal morphology of the bladder
Abnormal morphology of the urethra
Vaginal structural abnormalities
Breed predispositions
What are the clinical signs of urethral sphincter mechanism incontinence (USMI)?
Urinary incontinence
How do you diagnose urethral sphincter mechanism incontinence (USMI)?
Urethral sphincter mechanism incontinence is a diagnosis based on the exclusion of all other causes of these clinical signs
How can you medically manage urethral sphincter mechanism incontinence (USMI)?
Phenylpropanolamine
Ephedrine
Estriol
What is the mechanism of action of phenylpropanolamine?
Phenylpropanolamine is a sympathomimetic drug which can bind to the α1 adrenergic receptors at the internal urethral sphincter, increasing internal urethral spincter tone
What are the side effects of phenylpropanolamine?
Restelessness
Aggression
Hypertension
What is the mechanism of action of ephedrine?
Ephedrine is a sympathomimetic drug which can bind to the α1 adrenergic receptors at the internal urethral sphincter, increasing internal urethral spincter tone
What is the mechanism of action of estriol?
Estriol is a synthetic oestrogen which will upregulate the α1 adrenergic receptors at the internal urethral sphincter, increasing internal urethral spincter tone
What are the contraindications for estriol?
Male animals
Intact females
PUPD patients
What can you do if patients with urethral sphincter mechanism incontinence (USMI)?
Consider differential diagnoses
Try drugs in combination
Weight loss
Collagen injections into the urethra
Surgical articifical urethral sphincter
What are ectopic ureters?
Ectopic ureters are a congenital conditon where the ureters bypass the trigone of the bladder and insert elsewhere
What are intramural ectopic ureters?
Intramural ectopic ureters open into the bladder at a lower site than usual, usually the neck of the bladder or the urethra
What are extramural ectopic ureters?
Extramural ectopic ureters bypass the bladder and open into usually either the urethra or the vagina
What is the typical signalement for ectopic ureters?
Young animals (as this is a congenital condition)
What are the clinical signs of ectopic ureters?
Urinary incontinence
How can you diagnose ectopic ureters?
Ultrasound
Retrograde urethral contrast radiography
CT intravenous urethrogram
Cystography
How do you treat ectopic ureters?
Referral surgery
What is the main cause of lower urinary tract infections?
The main cause of urinary tract infections are ascending infections from the external environment (usually pathogens found in the faeces or the skin)
Which bacteria species are usually isolated in lower urinary tract infections?
E. coli
Staphylococcus
Streptococcus
Proteus
Enterococcus
Klebsiella
Which signalement is most prone to lower urinary tract infections (UTIs)?
Female dogs
Male dogs with prostatitis
What are the clinical signs of lower urinary tract infections?
Urgency to urinate
Haematuira
Dysuria
Stranguira
Pollakiuria
Bladder small and thickened on palpation
What can lower urinary tract infections progress to?
Urinary retention
Urinary incontinence
(T/F) Pyrexia and leukocytosis are rare in lower urinary tract infections
TRUE. Pyrexia and leukocytosis are very rare in lower urinary tract infections however they are seen in pyelonephritis
How do you diagnose lower urinary tract infections?
Urinalysis including urine culture and sensitivity
Which is urinary culture and sensitivity indicated?
Animals with lower urinary tract clinical signs
Animals with renal disease
Animals with non-specific clinical signs
Animals with diseases which predispose them to urinary tract infections
What is the best way to collect a urine sample of urinary culture and sensitivity?
Cystocentesis
What is asymptomatic bacteriuria?
Asymptomatic bacteriuria is where patients have bacteriuria in the absence of clinical signs
What is sporadic bacterial cystitis?
Sporadic bacterial cystitis is a bacterial infection of the bladder, with less than three episodes of cystitis within a twelve month period
How do you treat sporadic bacterial cystitis?
3 - 5 day course of antibiotics, ideally based on urine culture and sensitivity
Which antibiotics can you use to treat sporadic bacterial cystitis if you don’t have culture and sensitivity results?
Amoxycillin
Amoxycillin-clavulanate
Which drugs, other than antibiotics, can be used to treat sporadic urinary tract infections?
NSAIDS
What is a recurrent bacterial cystitis?
Recurrent bacterial cystitis is a bacterial infection of the bladder, with three or more episodes of cystitis in twelve months or one recurrence within three months. Recurrent bacterial cystitis can be relapsing or reinfection
What is the difference betwen a relapsed infection and a reinfection?
A relapsed infection is the persistence of the original bacteria which caused the infection, whereas a reinfection is where there is a new infection with a different bacteria
What can cause bacterial cystitis to relapse?
Inappropriate antibiotic
Inappropriate antibiotic dose
Inappropriate frequency or duration of treatment
Lack of owner compliance
Presence of a nidus of infection
Anatomical or funtional abnormalities
What can cause a bacterial cystitis reinfection?
Presence of a nidus of infection
Anatomical or functional abnormalities
How do you treat a recurrent bacterial cystitis?
Identify and treat the underlying causes
3 - 5 day course of antibiotics based on culture and sensitivity if a reinfection
7 - 14 day course of antibiotics if relapsed infection
(T/F) Recurrent bacterial cystitis should always be prescribed antibiotics based on urine culture and sensitivity
TRUE.
What are the potential complications of lower urinary tract infections?
Polypoid cystitis
Emphysematous cystitis
What is polypoid cystitis?
Polypoid cystitis is the formation of polyp-like growths on the bladder wall which cause inflammation and can be a nidus (focus) for infection
Which treatment option should you consider for polypoid cystitis?
Partial cystectomy
What is emphysematous cystitis?
Emphysematous cystis is the accumulation of gas in the bladder lumen and wall
What causes emphysematous cystitis?
Emphysematous cystitis is caused by certain types of bacteria, most commonly E. coli, which are capable of fermenting glucose and producing gas as a byproduct resulting in emphysema
Which disease can increase the risk of emphysematous cystitis?
Diabetes mellitus
What is the most common iatrogenic cause of lower urinary tract infections?
Urinary catheterisation
How can you reduce the risk of lower urinary tract infections secondary to urinary catheterisation?
Minimise trauma during catheter placement
Aseptic technique
Closed urinary collection systems
Reduce duration of catheter placement
What are the most common benign bladder masses seen in small animals?
Polypoid cystitis
Leiomyoma
What is the most common malignant bladder neoplasia seen in small animals?
Transitional cell carcinoma
Which dog breed is predisposed to bladder transitional cell carcinoma?
Scottish Terrier
What are the clinical signs of a bladder transitional cell carcinoma?
Haematuira
Dysuria
Stranguira
Pollakiuria
Urinary retention
Urinary incontinence (rare)
How can a bladder transitional cell carcinoma cause urinary retention?
A bladder transitional cell carcinoma can extend into the bladder neck and urethra, resulting in a physical obstruction in urine outflow
How do you diagnose a bladder transitional cell carcinoma?
Diagnostic imaging
Cystoscopy
Bladder biopsy
BRAF mutation test
How do you treat a bladder transitional cell carcinoma?
Surgical resection
Chemotherapy
NSAIDS
Why is surgical resection often impossible for bladder transitional cell carcinomas?
Transitional cell carcinomas mostly occur at the trigone region of the bladder which is the small triangular region of the bladder formed by the openings of the ureters and the internal urethral sphincter, which can make surgical resection challenging due to the close proximity and risk of damage to vital structures
Which chemotherpy drug is usually used for bladder transitional cell carcinomas?
Carboplatin
What is the risk of chemotherapy in urinary incontinent patients?
Patients with transitional cell carcinomas can develop urinary incontinence, and since chemotherapy drugs are excreted renally into the urine this can result in chemotherpay drugs being distributed around the owner’s house
What are the benefits of NSAIDS in the treatment of bladder transitional cell carcinomas?
NSAIDS have both anti-neoplastic effects against transitional cell carcinomas and anti-inflammatory effects
What are the general clinical signs of prostatic disease?
Haematuria
Urethral discharge
Faecal tenesmus
Dysuria
Urinary incontinence
Hindlimb lameness
Systemic clinical signs (sometimes)
How can prostatic disease cause faecal tenesmus?
Prostatic disease can cause prostatic enlargement which can compress the rectum and cause faecal tenesmus
How can prostatic disease cause dysuria?
Prostatic disease can compress the urethra and cause dysuria
Which diagnostic tests can be done to investigate prostatic disease?
Rectal examination
Haematology and biochemistry
Urinalysis (including culture and sensitivity)
Prostatic wash
Diagnostic imagine
Fine needl aspirate (FNA)
How should a normal prostate feel on rectal examination?
On rectal examination you should be able to feel the prostate ventrally and it should feel smooth, bilobed and non-painful
How do you carry out a prostatic wash?
- Sedate your patient
- Pass a urinary catheter into the bladder and drain the bladder
- Flush the bladder with sterile saline
- Move the urinary catheter back to the level of the prostate. An assistant will have to feel the prostate per rectum and tell you when they can feel the tip of the catheter
- Inject a small volume (2 - 5ml) of sterile saline into the urinary catheter and have your assistant massage the prostate per rectum for approximately one minute to encourage sloughing of prostatic cells into the saline
- Aspirate the fluid
- Submit the sample for cytology and culture
What is benign prostatic hyperplasia?
Benign prostatic hyperplasia is an age-related change seen in entire male dogs. Persistent hormonal stimulation of the prostate can result in hyperplasia of the prostate parenchyma, along with the formation of prostatic cysts and increased prostatic vascularity (which can cause bleeding)
What are the clinical signs of benign prostatic hyperplasia?
Asymptomatic
Haematuria
Haemorrhagic urethral discharge
Haematospermia
Faecal tenesmus
How do you diagnose benign prostatic hyperplasia?
Rectal examination
Ultrasound
Prostatic wash
How does benign prostatic hyperplasia feel on rectal examination?
On rectal examination, benign prostatic hyperplasia will be a symmetrically enlarged, non-painful prostate
Why should you do a prostatic wash if you suspect benign prostatic hyperplasia?
A prostatic wash should be done if you suspect benign prostatic hyperplasia as it can rule out inflammatory and neoplastic conditons
What is required for a definitive diagnosis of benign prostatic hyperplasia?
Biopsy and histopathology
How can you treat benign prostatic hyperplasia?
Surgical castration
Chemical castration
How long does it take surgical castration to begin to correct benign prostatic hyperplasia?
4 weeks
What are the main options for chemical castration?
Osaterone
Deslorelin
What is osaterone?
Osaterone is a tablet form of a testosterone receptor antagonist and thus prevents the persistent stimulation of testosterone on the prostate
How long does it take osaterone to begin to correct benign prostatic hyperplasia?
2 weeks
What is deslorelin?
Deslorelin is an implant GnRH agonist
How long does it take deslorelin to begin to correct benign prostatic hyperplasia?
At least a month
What are the contraindications for deslorelin to treat benign prostatic hyperplasia?
Deslorelin can cause initial swelling of the prostate which can worsen faecal tenesmus, so if patients are already presenting with faecal tenesmus, this form of treatment is contraindicated
What is bacterial prostatitis?
Bacterial prostatitis is the inflammation of the prostate due to a bacterial infection
What are the causes of bacterial prostatitis?
Ascending bacterial infection from the urethra
Haematogenous bacterial infection
Which signalement typically presents with bacterial prostatitis?
Entire male dogs
What are the clinical signs of acute bacterial prostatitis?
Haematuria
Haemorrhagic/purulent urethral discharge
Faecal tenesmus
Dysuria
Abdominal pain
Lethargy
Pyrexia
Anorexia
Vomiting
What are the clinical signs of chronic bacterial prostatitis?
Mild haematuria
Haemorrhagic/purulent urethral discharge
Recurrent lower urinary tract infections
Infertility
How do you diagnose bacterial prostatitis?
Rectal examination
Haematology and biochemistry
Urinalysis and culture
Ultrasound
Prostatic wash
How does bacterial prostatitis feel on rectal examination?
On rectal examination, the prostate can feel normal with bacterial prostatitis however it is likely to be painful with acute bacteria prostatitis but not with chronic bacterial prostatitis
How do you treat bacterial prostatitis?
It is important to check for bacteria prostatitis in entire male dogs presenting with bacteruria or bacterial cystitis as the treatment for bacterial prostatitis is quite different due to the blood prostate barrier - because of this you have to choose very specific antibiotics and adminsiter them for a longer duration
Which antibiotics can be used to treat bacterial prostatitis?
Trimethroprim (first line)
Fluoroquinolones (second line)
How long should you treat acute bacterial prostatitis with antibiotics?
4 week course of antibiotics
How long should you treat chronic bacterial prostatitis with antibiotics?
4 -6 week course of antibiotics
Which treatment method is recommended to prevent recurrence of bacterial prostatitis?
Castration following antibiotic treatment
What are the clinical signs of prostatic abscesses?
Haematuria
Haemorrhagic/purulent urethral discharge
Faecal tenesmus
Dysuria
Abdominal pain
Lethargy
Pyrexia
Anorexia
Vomiting
What is one of the main potential complications of prostatic abscesses?
Prostatic abscesses can cause septic shock if they rupture
How do you diagnose prostatic abscesses?
Rectal examination
Ultrasound
How does a prostatic abscess feel on rectal examination?
On rectal examination, the prostate will feel enlarged and asymmetrical if there is a prostatic abscess
How do you treat a prostatic abscess?
Surgical drainage and omentalisation
Percutaneous drainage
Castration (to prevent recurrence)
These are referral procedures
What are paraprostatic cysts?
Paraprostatic cysts are large cysts adjacent to but attached to the prostate via a stalk
What are the clinical signs of paraprostatic cysts?
Faecal tenesmus
Dysuria
Perineal mass
Clinical signs don’t usually arise until the cyst is very large
How do you diagnose a paraprostatic cyst?
Radiography
Ultrasound
How do you treat a paraprostatic cysts?
Percutaneous drainage
Castration (to prevent recurrence)
What is the most common form of prostatic neoplasia?
Prostatic carcinoma
Which signalement can present with prostatic neoplasia?
Entire or neutered male dogs
What are the clinical signs of prostatic neoplasia?
Haematuria
Haemorrhagic urethral discharge
Faecal tenesmus
Dysuria
Hindlimb lameness
Weight loss
Anorexia
How do you diagnose prostatic neoplasia?
Rectal examination
Radiography
Ultrasound
BRAF test
Prostatic wash
How does prostatic neoplasia feel on rectal examination?
Enlarged, firm, ± painful prostate with firm, irregular nodules
May be able to palpate enlarged sublumbar lymph nodes
How do you treat prostatic neoplasia?
Chemotherapy
NSAIDS
There is no curative treatment for prostatic neoplasia
Which referral treatment can you recommend to owners for prostatic neoplasia?
Coil embolisation which reduces blood flow to the tumour to attempt to reduce the rate of growth
