Benign diseases of the Prostate Flashcards
what is the average size of the prostate
15cc
where does the prostate lie
sits underneath the bladder - surrounded by important structures
why is the prostate referred to as a secondary sexual organ
secretes an alkaline milky fluid that makes up around 30% of semen - alkalinity of sperm allows it to survive longer in acidic environment of the vagina - so without the prostate you could still ejaculate but sperm won’t work
what is terminal dribbling and how does it occur
when after voiding and walking away a small amount of urine passes out - as you get older the angle of the urethra in men becomes more acute - creates a “bulb” - bulb of urethra collects a puddle of fluid - pressure from walking causes last bit of urine to be pushed out
can you differentiate different parts of the prostate under the microscope
no - all look the same
what are the 4 zones of the prostate
transition zone, central zone, peripheral zone, anterior fibromuscular zone
what is clinically important to know about the peripheral zone
85% of prostate cancers form here - reason for rectal examination in identifying them
what are the three types of benign prostatic disease
BPE - benign prosatatic enlargement
BPH - benign prostatic hyperplasia
BPO - benign prostatic obstruction
of the three types of benign prostatic disease, which one can be seen histologically under a microscope
Benign prostatic hyperplasia
what are the two group of symptoms referred to as
BOO - bladder outflow obstuction
LUTS - lower urinary tract symptoms
what does the half diagram show
venn diagram showing cross over between LUTS, BOO and BPE
what are the characteristics of benign prostatic hyperplasia
fibromuscular and glandular hyperplasia
- predominantly in the transition zone
- progressive condition resulting in blader outflow obstruction (BOO)
what % of men have BPH at 60yrs and 85yrs respectively
50%
90%
how can prostate growth be stopped
- removal of prostate
2. block testosterone
what indicator can differentiate between fibromuscular and glandular hyperplasia
the size of the prostate and how it responds to different treatments
what system is used to give an indication of prostate health
International prostate symptom score sheet
what are the two groups LUTS symptoms can be divide into
- voiding (obstructive) symptoms
2. Storage (irritative) symptoms
list the common voiding (obstructive) LUTS
hesitancy, poor stream, terminal dribbling, incomplete emptying
list the common storage (irritative) LUTS
frequency, nocturia, urgency +/- urge incontinence
what can be used to track frequency
frequency volume chart
what is the normal average capacity for men and women respectively
~500
~400
what is the average frequency of urination per day
4-6 times
what are the 3 areas to be examined for BPH
- abdomen - palpable bladder
- penis - external urethral metal stricture, phimosis
- digital rectal exam - assess prostate size,suspicious nodules to firmness
what should be looked for in a urinalysis for BPH
blood, signs of UTI
what 8 investigations should be undertake for BPH
- MSSU (mid stream sample urine)
- flow rate study
- post-void bladder residual USS
- Bloods - PSA, urea+creatinine (if chronic retention)
- renal tract USS if renal failure or bladder stone suspected
- flexible cystoscopy if haematuria
- urodynamic studies in selected cases
- TRUS- guided prostae biopsy if PSA raised or abnormal DRE
what is PSA
Prostate Specific Antigen - a serum protease - something in the blood specific to prostate but not to prostate cancer
- in benign disease can help determine size
- in malignant disease can help determine response to treatment
what do the top and bottom lines in a flow rate study show
top - max flow rate ml/s
bottom - volume urinated
what are the two common causes for a pathological flow rate reading
- problem with pressure exerted from bladder
2. problem with opening
what are the two types of BPO
uncomplicated and complicated
what are the three treatment groups of uncomplicated BPO
- watchful waiting
- medical therapy
- surgical intervention
what medical therapy is used for uncomplicated BPO
- Alpha blockers
- 5 alpha reductase inhibitors (finasteride or dutasteride)
- combination
what surgical intervention is used for uncomplicated BPO
- TURP - transurethral resection of prostate (prostate <100cc)
- open retropubic or transvesical prostatectomy (prostate size >100cc)
- endoscopic ablative procedures
what is the mainstay treatment for uncomplicated BPO
ALPHA BLOCKERS
- work fast - within 48hrs see improvement
- cause smooth muscle relaxation and antagonise the “dynamic” element to prostatic obstruction
**work best for fibromuscular prostate blockage (due to nature of acting on alpha-1a receptors in smooth muscle of prostate
what is the main alpha blocker used for BPO in the UK
tamsulosin - as it is highly selective to alpha-1a
what are the 4 groups o alpha blockers
- non-selective (ie alpha 1 and 2) phenoxybenzamine
- selective short acting - parson, indoramin
- selective long acting - alfuzosin, doxazosin, terazosin
- highly selective (i.e. alpha-1a) tamsulosin
what are contraindication for tamsulosin
if going for cataract surgery
parkinsons - can lower BP
what is the action of 5a-reductase inhibitors
convert testosterone to dihydrotestosterone
what are the two 5a-reductase inhibitors currently available
- finasteride (5AR Type II inhibitor)
2. dutasteride (5AR Type I and II inhibitor)
what are the roles of 5ARIs
- reduce prostate size - esp on larger prostates
- reduce risk of progression to BPE
- reduces LUTS
- can reduce prostatic vascularity and therefore reduce haematuria due to prostatic bleeding
- potential role in reducing rate of low and intermediate prostate cancer BUT rate of high prostate cancer goes up
what is the gold standard surgery for BPO
TURP - very effective in receiving symptoms - improves urodynamic parameters (90% efficacy at 1 year)
what are complications of TURP
bleeding, infection, retrograde ejaculation, stress urinary incontinence, prostatic regrowth causing recurrent haematuria or BOO
what are complications of BPO
- progression of LUTS
- acute urinary retention
- chronic urinary retention
- urinary incontinence (overflow)
- UTI
- bladder stone
- renal failure from obstructed ureteric outflow die to high bladder pressure
what is a red flag sign for chronic retention
sudden onset bed wetting - may be no further symptoms
what is the treatment for complicated BPO
SURGICAL intervention - medical therapy will usually not suffice
eg cystolitholapaxy and TURP for patients with BPO and bladder stones
when may BPO patients NOT need treatment
if residuals relatively low, asymptomatic and no complications
what treatments could be given to BPO patients that are unfit for surgery
- long term urethral/suprapubic catheterisation
2. clean intermittent self catheterisation
what are the complications of long term catheterisation
may develop problems with catheter trauma, blockages, frank haematuria, recurrent UTI
what is the definition of acute urinary retention
painful inability to void with a palpable and permissible bladder
what are the residuals of acute urinary retention
vary from 500ml to >1 depending on time lag seeking treatment
what is the main causes of acute urinary retention
main risk factor BPO BUT can also occur independently of BPO e.g. UTI, urethral stricture, post op causes, excess alcohol, acute surgical or medical problems
for people with BPO, how can acute urinary retention occur
- spontaneously - i.e. natural progression
2. triggered by unrelated event e.g. constipation, alcohol excess, post operative causes, urological procedure
what is the immediate treatment for acute urinary retention
catheterisation (either urethral or suprapubic)
what other treatments should be considered
- treatment of the underlying trigger if one present
- if no renal failure start alpha blocker immediately and remove catheter in 2 days - 60% will void successfully
- if failure to void after 2 days recatheterise and organise TURP - after 6 weeks
what are the complications of acute urinary retention
- UTI, post-decompression haematuria, pathological diuresis, renal failure, electrolyte abnormalities
what is the definition of chronic urinary retention
painless, palpable and percussible bladder after voiding
what are the residuals of chronic urinary retention
patients able to void but can have residuals from 400ml to >2 L depending on stage of condition i.e. wide spectrum
what is the main etiological factor for chronic urinary retention
detrusor underactivity
- primary - ie primary bladder failure
- secondary - ie due to longstanding BOO, such as BPO or urethral stricture
how does chronic urinary retention usually present
present as LUTS or complications (e.g. UTI, bladder stones, overflow incontinence, post-renal or obstructive renal failure)
what patients with chronic urinary retention mayn’t need treatment
asymptomatic patients with low residuals
what is the immediate treatment for chronic urinary retention
catheterisation (either urethral or suprapubic)
what are complications of chronic urinary retention
UTI, post-decompression haematuria, pathological diuresis, electrolyte abnormalities (hyponatraemia, hyperkalaemia, metabolic acidosis), persistent renal dysfunction due to acute tubular necrosis
what are the features of pathological diuresis
- urine output >200mk/hr
- postural hypotension (systolic differential >20mmHg between lying and standing)
- weight loss
- electrolyte abnormalities
How can pathological diuresis be treated
IV fluids (total input = 90% of output) and monitor closely - liaise with renal team
what is further treatment for chronic urinary retention
long term urethral or suprapubic catheterisation, CISC or TURP
when is TURP more successful - acute or chronic renal retention
more successful in ACUTE
BUT
within chronic:
patients with HIGH pressure chronic more successful than patients with LOW pressure chronic
