Urinary Incontinence and Benign Prostatic Hyperplasia Flashcards
What is BPH?
Benign Prostatic Hyperplasia
How and when does the prostate develop in utero / gestation?
Develops between weeks 10-16 of gestation from epithelial buds which branch out from the posterior aspect of the urogenital sinus to invade the mesenchyme
Influenced by the hormone dihydrotestosterone, which is produced by epithelial cells
Stromal-epithelial interaction is important, dihydrotestosterone acts on mesenchymal androgen receptors
What is the arterial supply for the prostate?
Arises from branches of the inferior vesical artery
This provides the prostatic artery divides into urethral and capsular groups of arteries
Urethral group give rise to Flock’s and Badenoch’s arteries (both at 1 & 11 o’clock and Badenoch’s arteries approach it at 5 & 7 o’clock)
The capsular branches of th eprostatic artery run with the cavernosal nerves
What is the venous drainage of the prostate?
The venous drainage is via the peri-prostatic venous plexus
This also receives the deep dorsal vein of the penis and numerous vesical veins
The periprostatic venous plexus eventually drains into the internal iliac vein
What is the lymphatic drainage of the prostate?
Mainly to the obturator nodes and then the internal iliac chain
What is the zonal anatomy of the prostate?
They are also called McNeal’s zones
- Transition zone
- 10% of the glandular tissue of the prostate
- Site of origin of benign prostatic hyperplasia - Central zone
- 25% of the glandular tissue of the prostate - Peripheral zone
- 65% of the glandular tissue of the prostate
What is the role of the capsule?
The capsule transmits the ‘pressure’ of tissue expansion to the urethra and leads to an increase in urethral resistance
How is active smooth muscle tone regulated?
Active smooth muscle tone is regulated by the adrenergic nervous system
(alpha-1A) ⍺1A is the most abundant adrenoceptor subtype in the human prostate
What is the function of the prostate?
Liquify the ejaculation
What is Lower Urinary Tract Symptoms (LUTS)?
Non-specific term for symptoms which may be attributable to lower urinary tract dysfunction
What is meant by Benign Prostatic Enlargement (BPE)?
Clinical finding of enlarged prostate
i.e. during rectal examination - feel of an enlarged prostate
What is meant by Benign Prostatic Hyperplasia (BPH)?
Histological diagnosis - increase in number of cells
What is meant by Bladder Outflow Obstruction (BOO)?
Urodynamically (urodynamic = test for finding out how your bladder, sphincter, and urethra are working) proven obstruction to passage of urine
When this obstruction is caused by BPE, it is called BPO (benign prostatic obstruction)
What is meant by Benign Prostatic Obstruction (BPO)?
BOO caused be BPE
What is meant by Benign Prostatic Hypertrophy?
Pathologically incorrect - increase in cell size
What is the pathophysiology of BPH?
Increased number of epithelial and stromal cells in the peri-urethral area of the prostate in response to androgens (testosterone) and growth factors
Results in increased urethral resistance (as enlarged prostate puts pressure against the walls of the urethra) resulting in compensatory changes in bladder function
Can lead to reduced urinary flow, increased urinary frequency, urgency and nocturia
How does bladder function change in BPH to lead to reduced urinary flow, increased urinary frequency, urgency and nocturia?
Detrusor = smooth muscle wall of the bladder
The detrusor muscle remains relaxed to allow the bladder to store urine, and contracts during urination to release urine
The detrusor muscle pressure required to maintain urinary flow in the presence of urethral (outflow) resistance happens at the expense of normal bladder storage function
The urethral obstruction induces changes in the detrusor function - this causes the BPH related symptoms
What is the prostate capsule and how does it contribute to LUTS?
The capsule transmits the ‘pressure’ of tissue expansion to the urethra and leads to an increase in urethral resistance
Does the size of the prostate predict the degree of obstruction?
No, there is no correlation - other factors e.g. dynamic urethral resistance, the prostatic capsule, and anatomic pleomorphism, are more important in the production of clinical symptoms than the absolute size of the prostate
What is smooth muscle in BPH representative of?
Prostatic smooth muscle represents a significant volume of the gland
How can urethral resistance be changed?
Urethral resistance can be increased by active and passive forces
What is the active smooth muscle tone in the prostate regulated by?
The adrenergic nervous system = alpha-1A is the most abundant adrenoreceptor in the prostate
What is LUTs related to in men with BPH?
LUTS caused by obstruction induced changes in bladder function rather than the symptoms being caused directly by the outflow obstruction
This is shown because approx. 1/3 of men continue to have significant voiding (urinating) dysfunction even after surgical relief of obstruction
What are the obstruction induced changes in bladder function?
- Changes that lead to detrusor instability or decreased compliance are clinically associated with symptoms of frequency and urgency
- Changes associated with decreased detrusor contractility are associated with further deterioration in the force of the urinary stream, hesitancy, intermittency, increased residual urine and sometimes detrusor failure
What are the voiding (urinating) and storage symptoms of BPH clinically?
Overactive bladder and decreased stretchiness of the bladder = reduced ability of the bladder to contract and increase pressure leading to:
Voiding symptoms: reduced flow, hesitancy, incomplete emptying, strangury, intermittence
Storage syptoms: frequency (daytime and nocturia), urgency, incontinence
Other symptoms: visible haematuria, infection
What is really important to ask about for lower urinary tract symptoms?
Fluid intake
What are some examinations conducted for suspected BPH?
General examination Palpable bladder Ballotable kidneys Phimosis Meatal stenosis Enlarged prostate on DRE (digital rectal examination), size, consistency, nodules, anal tone and sensation
What investogations are performed for suspected BPH?
Urine dipstick
Flow rate + PVR (postvoid residual) - asked to urinate and then use USS to see how much urine is still remaining in the bladder
IPSS questionnarie - designed specifically to ask about prostate enlargement
Bladder diary - intake, output, and frequency
USS KUB (ultrasound scan kidneys, ureters, bladder) if impaired renal function, loin pain, haemturia, renal mass on examination
PSA (prostate specific antigen test), creatinine
Flexible cystoscopy in some circumstances
TRUS (trasnrectal ultrasound scan) prostate
Urodynamic studies = test for finding out how your bladder, sphincter and urethra are working
What is the conservative management for BPH?
Watchful waiting and lifestyle changes - targetted using their bladder diaries
e.g. less tea / coffee, not drinking later into the night
What are the medical / pharmacological management options for BPH?
Pharmacological treatment:
- alpha-adrenergic antagonists = reduction in symptoms of 30-40% and improvement in flow rates of 16-25% by relaxing the bladder neck to allow for easier passage
e.g. Tamsulosin, alfuzosin, doxazosin
Side effects include: lightheadedness from lowered BP, retrogade (dry ejaculation) - 5-alpha-reductase inhibitors = prevents disease progression, reducing the development of AUR (urinary retention) / requirement for surgery, can help shrink the prostate
e.g. Finasteride, Dustasteride
Usually used for super large prostates i.e. >30g - Combination therapy
What are the surgical management options for BPH?
TURP = trans-urethral resection of the prostate - cystoscope placed inside urethra and prostate tissue shaved away
Rezum = inject steam into the prostate
UroLIFT = pinning back the prostatic lobes
Millin’s prostatectomy = old surgical procedure where prostate is removed via bladder
Embolisation = coils into the vessels that provides blood supply to the prostate to shrink it
HoLEP = laser nucleation of the prostate
What is urinary incontinence (UI) and what is its epidemiology?
UI = involuntary loss of urine
UI is a significant health problem worldwide associated with considerable social and economic impact on individuals and society
In women, prevalence 5-72% among community-dwelling women
It may be significantly under-reported as it is an embarrassing problem to many women
Women with stress incontinence (SI) are less likely to seek help than those with overactive bladder (OAB)
What are the different types of urinary incontinence?
Urinary incontinence (UI) = any involuntary loss of urine
Stress (urinary) incontinence (SI) =
the complaint of involuntary leakage on exertion /sneezing/coughing
Urge (urinary) incontinence (sometimes reffered to as OAB - overactive bladder) = the complaint of an involuntary leakage accompanied by or immediately preceded by urgency
Mixed urinary incontinence =
the complaint of an involuntary leakage of urine associated with urgency and also with exertion, effort, sneezing or coughing
Continuous incontinence = continuous leakage (could be suggestive of a fistula etc.)
Overflow incontinence =
leakage associated with urinary retention
Nocturnal enuresis =
the complaint of loss of urine occurring during sleep
Post-micturition dribble =
the complain of an involuntary loss of urine immediately after passing urine (usually in men, after full stream of urine, few drops come out at the end)
What are the causes of urinary incontinence?
Increasing age Pregnancy and vaginal delivery - due to effects on pelvic floor and pressures on the bladder Obesity Constipation Drugs e.g. ACEi Smoking Family History Prolapse / hysterectomy / menopause
What are the investigations done for urinary incontinence (UI)?
Urine dipstick = check for infection
Flow rate and PVR (postvoid residual) = useful for finding out if they are leaking due to overflow (too full) or if their bladder is really small
Bladder diary
Pad tests = patients wear pads, and weigh 24hrs worn of pads against a dry pad
Counting number of pads is useless due to frequency of changes
Patient symptom scores/validated QoL Questionnaire = how bothered the patient is by urinary incontinence
Urodynamic/video-urodynamic studies = mainstay of diagnosis of UI
What is the defintion and epidemiology of stress (urinary) incontinence (SUI / SI)?
SUI / SI = involuntary loss of urine on effort or physical exertion or on coughing or sneezing
More common in women of young to middle age
Uncommon in men who have not had prostate surgery
What are the 5 causative theories of SUI/SI in women?
- Urethral position theory
- Intrinsic sphincter deficiency
- Integral theory
- Hammock theory
- Trampoline Theory
What are the conservative / non-surgical interventions for SUI/SI?
Lifestyle changes
- Weight loss
- Cessation of smoking
- Modification of high/low fluid intake
Supervised pelvic floor exercises - patients that try to do them alone often don’t do them correctly
Bladder re-training
What are the medical / pharmacological options for SUI/SI?
Oestrogen therapy - examine the perineum of a woman with UI, if there is evidence of atrophy i.e. signs of low oestrogen)
Important because there are oestrogen receptors in the urethra, urethral sphincter, pelvic floor, base of the bladder and vagina = important in maintanence of continence
So topical oestrogen usually prescribes, sometimes oral medication e.g. Duloxetine which helps to increase the closure pressure of the urethral sphinctel but many side effects to ineffective long-term treatment
Oral medical therapy in rare cases
What are the surgical options for SUI/SI?
Occlusive e.g. bulking - collagen around urethra to cause physical obstruction, compressive (AUS)
Artificial urinary sphincter - part of the device goes around the urethra to place pressure on it - button needs to be pressed to get rid of the pressure so they can pass urine
Supportive e.g. mid-urethral sling - prevents too much movement of the urethra and supports urethral sphincter, colposuspension - support the bladder
Ileal conduit diversion - suitable for someone who has been thorugh the other options but still continues to have significant leakage
What are the 3 causative theories of SUI/SI in men?
SUI/SI normally occurs in men who have had prostatectomies for prostate cancer or benign prostate sugery - removal of prostate = damage to internal sphincter, external sphincter or nerve damage
- Sphincter incompetence - weakness in external urethral sphincter
- Reduction in urethral sphincter length = less efficient in contracting
- Post-operative strictures - in the area of the urethral sphincter
What are the 5 structures that control continence in men?
5 structures control continence:
- Detrusor muscle
- Internal sphincter (in the bladder neck)
- Ureterotrigonal muscles
- Levator muscles = pelvic floor
- Rhabdosphincter (external sphincter muscle)
What are the non-surgical / conservative treatments for SUI/SI?
Lifestyle changes weight loss cessation of smoking modification of high/low fluid intake Supervised pelvic floor exercises Bladder re-training
What are the medical / pharmacological treatments for SUI/SI?
Oral medical therapy in rare cases
e.g. Duloxetine - not a good option long-term
What are the surgical treatments for SUI /SI?
Occlusive e.g. bulking, compressive (AUS)
Supportive (suburethral sling)
Ileal conduit diversion
What is urge urinary incontinence (UUI)?
Pathophysiology of overactive bladder (OAB) is not well understood
OAB is a symptom syndrome: urinary frequency, urgency, nocturia with or without leak
OAB prevalence (NOBLE study) 16% in men and women
How do men and women differ in terms of urgency and leaking?
But men have a higher prevalence of OAB-dry (13.4%) cf. 7.6% in women - i.e. urgency without leaking
Women have a higher prevalence of OAB-wet (9.3% vs 2.6% in men - i.e. urgency with leaking
What else could it be if its not UUI?
Differential diagnosis = UTI DO = detrusor overactivity Urethral syndrome Urethral divertivulum Interstitial cystitis Bladder cancer Large residual volume
What are the conservative / non-surgical treatments for UUI?
Lifestyle changes
- Decreasing caffeine intake
- Stopping smoking
- Losing weight if obese
Bladder re-training
Pelvic floor muscle exercises
What are the medical / pharmacological treatments for UUI?
Efficacy is 50-75%
Anti-cholinergics e.g. solifenacin, tolterodine, trospium
- Side effects = dry mouth, blurry vision (temporary), constipation
Beta-3-agonists e.g. betmiga
- Side effect of raising BP, prolong QT interval
What are the surgical treatments for UUI?
Posterior Tibial Nerve Stimulation (PTNS) = aeedle placed next to the PTNs to provide electrical stimulation once a week for 12 weeks
Efficacy = helps 40% of patients
Relatively low risk
Intravesical injection of botulinum toxin A
= botox treatment in bladder = under local anaesthetic = repeated every 6-9 months
Efficacy = 36-89%, mean efficacy is 70%, upto a mean time of 6 months
Neuromodulation = into S3 foramina = can be switched on and off to modulate bladder and sphincter Efficacy = 50% cure rate, 25% significant improvement of symptoms, 25% failure rate
Clam (augmentation) cystoplasty - open up bladder and place some bowel in the middle to interrupt the contractions of the bladder
Efficacy = 50% cure rate, 25% significant improvement of symptoms, 25% failure rate
Long term risks / side effects
Urinary diversion is an option if all else fails in very severe cases
