Urology Flashcards
Common causes of haematuria
- Tmours
- Renal calculi
- BPH
- Trauma
- Coagulopathy
- congenital or acquired abnormalities (Polycystic renal disease, urethral stricture)
____% of macroscopic haematuria is caused by urological cancer.
A single episode of microscopic haematuria has a risk of approximately ___% of being associated with malignancy.
What implications does this have for malignancy screening?
20% of macroscopic haematuria is caused by urological cancer.
A single episode of microscopic haematuria has a risk of approximately 4% of being associated with malignancy.
Therefore all patients with haematuria should be screened for malignancy, especially maxcroscopic
If someone has haematuria, what do we want to know from the hx?
- painfull or painless
- ?fever
- ?weightloss or anorexia
- Is the blood
- initial urethra or prostate
- terminal bladder base or prostate
- mixed anywhere
- Trauma
- Voiding symptoms
- Previous renal tract hx
- smoking
Investigations of someone with haematuria
- FBC, U&E’s, LFT, CRP
- MSU
- USS or CT IVU and a flexible cystoscopy is required
- ?PSA
What are the common pathogenic causes of a UTI
- E.coli
- Staphylococci
- Enterococci
- Proteus mirabilis
How can protease mirabilis cause stones
it is a urease producing orgnaism, and alkalinises the urine, precipitating phosphates from the urine to cause stones
What are the three major routes that urinary tract infection takes?
- ascending infection; from urethra, commonest
- haematogenous spread: TB and some perinephric abscesses
- Direct extension fistulas from colon or vagina
What mechanisms do bacteria use to infect the bladder?
- Vagina and periurethra normally colonised by lactobaccilus, these get replaced with recurring infections
- Type-1 fimbrae allow bacterial adherence to the bladder uro-epithelium
- P-fimbrae bind their P-blood group antigens on the epithelial surface and are associated with renal infection
- Bacteria release endotoxinss causing a decrease in ureteric perstalsis allowing for bacteria to ascend
What things can increase your host susceptibility for UTI’s
Children who express P1 antigens are at a greater risk of pyelonephritis, whilst those expressing ABO and Le B antigens are less susceptible
A high epithelial count on MSU can indicate?
An inadequate MS sample
Can a diagnosis of UTI can be made with lower bacterial counts if a single pathogenic organism is cultured
yes
Pyuria without organisms suggests what?
Possible renal calculi or renal tuberculosis
Investigation for renal TB?
Requires at least 3 early morning urines (EMU) for acid-fast culture
What are common contaminents of a MSU that don’t actually indicate infection?
Lacto bacilli, streptococci, diptheroids, gardenerella, mycoplasma
acute bacterial cystitis: Treatment
- A 3-day course of:
- Trimethoprim
- Nitrofratoin
- Amoxicillin Clavulanate
- Norfloxacin
Acute pyelonephritis: Treatment
- A 7-day dose of oral antibiotics +/- fluid replacement and admission:
- Gentamicin: for patients with normal kidney function
- Amoxicillin clavulanate (augmentin) or ceftriaxone
- Ciprofloxacin: well absorbed and in non-vomiting patients can be given orally
What things can you do to relieve symptoms of a UTI, and what do you need to be careful of…
High fluid intake and alkalinisation of urine
Mixtures of sodium bicarbonate and citrate can relieve dysuria
****alkaline urine decreases the efficacy of nitrofuratoin
Suitable regiemes of prophylactic antibiotics for recurrent UTI’s?
- Low dose antibiotic last thing at night OR
- Post-coital miturationa dn low dose antibiotic
Agent’s
- trimethoprim 100mg for 6-12 weeks
- nitrofuratoin 50mg for 6-12 weeks
How does epididymitis present and what is it usually caused by?
Common cause of scrotal pain (espeically in their 20’s) that comes on rapidly. Associate with dysuria, fever and sometimes urethral discharge.
Often caused by STI’s
- Neisseria gonorrhoea or Chlaymydia
- Coliform (in elderly)
What can be a non-infective cause of epididimytis?
Heavy lifting can cause urinary reflux into the vas and cause a chemical epididymitis
On examination of a patient with epididymitis, what would you classically see?
Tenderness localised to the epididymis which is enlargedm while the testes are normal/non-tender.
** in more advanced cases both the testis and epididymis may be enlarged/tender and the scrotal skin erythematous and indurated.
What investigations do you do for suspected epididymitis?
- MSU and urine for
- First-void urine for Chlamydia and gonorrhea nucleic acid amplificiation test (NAAT)
- Urethral swabs (alterative to NAAT)
- Scrotal USS: not always required: to confirm dx and rule out complications eg; abscess
Management of Epididymitis?
- Bed rest 48hrs
- Antibiotic
- STD: azithromycin 1g stat and ceftriaxone 500mg IM stat
- also notify sexual partners and abstain for 7 days
- Coliform: Amoxy/clav 7/7
- STD: azithromycin 1g stat and ceftriaxone 500mg IM stat
- Advise patient scrotum will take 7/7 to return to normal size
What are the two subtypes of urethritis and how is it characterised in terms of presentation?
Gonococcal urethritis (GU) and nongonococcal urethritis (NGU)
Characterised by dysuria and urethral discharge
***BOTH are STD’s***
What differentiates GU from NGU
-
GU: Neisseria gonorrhoeae (Gram + diplococci)
- ***up to 1/3 of these infection are associated with a coinfection with chlamydia
- Incubation up to 10 days
-
NGU: Chlamydia trachomatis is the most common cause (20-65%)
- also ureplasma urealyticum and mycoplasma
- Incubation 7-21
What risk factors predisppose you to GU/NGU?
- AGe 15-24
- African american
- Sexual activity + multiple sexual partners
- 10% risk post exposure
Therefore a sexual history is very important
What symptoms will you see in GU versus NGU?
BOTH can have a painful penile urethra
NGU urethral d/c: clear/whitish fluid
GU urethral d/c: thick and purulent
BOTH uncommon to have systemic symptoms
Also exam scrotum + DRE
What will you see in a urine analysis of a patient with GU/NGU and when should it be perfomred
Sample should be obtained >1hr post last void
*upto 30% of patients with urethritis will have no WBC in urine*
- NAAT performed on the first 30 cc of voided urine to asses urine flora. (This covers . C. trach and N. gonorr)
- Urethral swab for gram stain and culture can be performed for other causes (inserted 1-2cm in and 1-2hr post void)
Treatment of GU and NGU?
- GU:
- Uncomplicated: Ceftriaxone 500mg IM stat AND azithromycin 1g po stat
- Complicated: Ciprofloxacin 500 mg PO stat AND azithromycin 1 g PO
- NGU
- Azithromycin 1g PO once or
- Doxycycline 100mg bid for 10-14 days
*** both N gonorrh and C trach should be empiracally treated when the other is present
How should patients with confirmed GU/NGU who have been treated be followed up, and what sexual activity advice do you give them?
Follow-up at 7 days: resolution of symptoms
Followup at 3 months: detect re-infections
Advice:
- avoid sexual intercourse until cured
- Sexual partners within 60 days or diagnosis or symptoms should be evaluated and treated
Why do we get so concerned about obstruction or stasis (obstructive nephropathy)
Because either can lead to hydronephrosis, atrophy of the kidney and renal failure (if bilateral or if patient has one kidney)
Superimposed sepsis can also occur
Congenital causes of obstructive nephropathy?
- Congenital obstruction of posterior urethral valves
- Spina bifida (s2,3,4 damage → poor detrusor function of bladder)
- Strictures or reflux of vesicoureteral or pelvicouteric junction
Causes of acquired Obstructive nephropathy
- Urethral stricture: trauma, std, catheter
- BPH
- Prostatic cancer
- cervical cancer
- Malignant infiltration from bladder
- Calculi
- Detrusor failure (diabetes, spinal cord . sompression)
- Retroperitoneal fibrosis
- Iatrogenic ureter injury
What are the stages of compensation and decompensation the bladder undergoes in response to obstruction or stasis distally?
“the stages of compensation”
Compensation
- Bladder musculature hypertrophies: Up to 2x, in order to balance increasing resistance
- Initially bladder emptying is still possible
- Trabeculation occures
- Pressure continues to increase (upto 2-4x the normal 30cms water)
- Diverticula occur as mucosa is pushed between the superficial muscle bundles
Decompensation
- Detrusor muscle may decompensate
- incomplete emptying
- Residual urine forms post-voidally
- Painful urinary rentention OR chronic urinary retention result
What is trabeculation of the bladder
When as a compensatory response the bladder wall becomes hypertrophied with individual muscle bundles standing out, becoming taut and giving a coarsely interwoven appearance to the mucosal surface.
What effect does distal obstruction or stasis have on the Ureters?
- Nothing in the early stages: intravesical pressure not transmitted to ureters as ureterovesical valve still competen
- As the UV valve decompensates, vesicoureteric reflux occurs
- Ureteral muscultature will increase in thickness in its attempt to push the urine downward
- This can lead to attneuation of the uterers and they lose their contractile power
What effect does distal obstruction or stasis have on the kidneys?
Pressure in renal pelvis should be ~0
- Increasing pressure can cause calyces+pelvis may dilate
- degree of hydronephrosis depends of the duration, degree and site of the obstruction (higher = worse outcome)
- Initially compensatory hypertrophy
- Later muscle becomes dilated and thin due to atrophy, necrosis and ischaemia
- As pressure increases, the closer it gets to GFP (30-40mmHg) the less urine can be secreted
- The concentrating power of the kidney is lost → kidney failure results
* if unilateral then the other kidney will take over and may overcomensate/also fail
Symptoms of lower obstruction (urethra and bladder) versus higher (ureter and kidney)
Lower Obstruction:
- hesitancy, weak stream, intermittent flow, incomplete emptying
- Acute urinary retention can be the presentation
Upper Obstruction:
- Flank pain that radiates along ureter, haematuria (if stone)
- If infection occurs; chllls, fever, buring urination, cloudy urine
- Progressive renal failure: N+V, weight loss, pallor
What is nephrolithiasis and how common is this
Urinary calculi.
3rd most common disease behind infections and prostate disease.
M>F
30-50yrs
What type of urinary calculi are common and can they be seen on xray (radiopaque)
90% are radiopaque and most contain calcium
(10% gallstones can be seen on xray)
How does urinary pH impact uric acid stone formation
Acidic urine promotes uric acid stone formation as it reduces solutbility
What are struvite stones?
a combination of Mg-NH4 phosphate and Ca-CO3 appatite
Staghorn calculi typical
Due to increased ammonia production by urea splitting bacteria eg; proteus or kliebsiella
How are cystiene stones inherited?
Autosomal reccessive, hereditary
How do urinary stones typically present in relation to their site?
- Upper: flank/back/abdo pain, dull and can have radiation to anterior abdo
- Mid/lower: severe sharp, colicky, intermittent, can radiate to the groin or penile tip
- Lower (near bladder): urinary frequency and dysuria. Can have sudden voiding stasis
All associated with nausea + vomiting and microscopic haematuria
What imaging do you want for ureteric calculi?
Non-contrast CT
USS if pregnant (may only show dilitation and no stone)
Although 90% of ureteric stones <5mm will pass spontaneous, with analgesia and increased fluids enough to manage (FU in 4-6weeks for updated imaing) what are the indications to do more serious management/referral?
- obstruction in a single kidney
- bilateral obstruction
- infection or sepsis
- VERY increased Creatinine
- Unable to tolerate oral intake
- Severe Pain
Apart from fluids + analgesia (NSAIDS EG: diclofinac) + antiemetics what else can you give them to help spontaneously pass the stone?
A low-dose alpha blocker eg; doxazosin
this relaxes the ureter
However this is contraversial in its efficacy
Elective surgical management of ureteric stones?
- Percutaneous nephrolithotomy (OCNL) if >20mm
- Extracorporeal shock wave lithotripsy (ESWL) <20mm
- Ureteroscopy with laser stone fragmentation
Reccomendations of living to prevent ureteric stones?
- Fluid intake to produce 2L urine/day
- low sodium, moderate calcium, low animal protein, high fibre diet
