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 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 drains into vesical plexus and internal iliac vein
What is the lymphatic drainage of the prostate?
internal iliac lymph nodes and sacral nodes
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?
secrete 75% of seminal fluid which liquifies coagulated semen after deposition in the female genital tract.
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 Benign Prostatic Obstruction (BPO)?
Bladder outflow obstruction 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 both lateral lobes and median lobes in response to 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
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 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 is really important to ask about for lower urinary tract symptoms?
Fluid intake
What investogations are performed for suspected BPH?
Investigations:
- Urine dipstick/ MCS
- Post-void residual
- Voiding diary - intake, output, and frequency
- IPSS questionnarie - designed specifically to ask about prostate enlargement
Bloods:
- PSA (prostate specific antigen test)- predict prostate volume
Imaging:
- USS KUB (ultrasound scan kidneys, ureters, bladder) if impaired renal function, loin pain, haemturia, renal mass on examination
- Flexible cystoscopy (if cancer concern)
- TRUS (transrectal ultrasound scan) prostate
Other:
- Urodynamic studies = test for finding out how your bladder, sphincter and urethra are working
What is the management for BPH?
1. Non-bothersome: Behavioral management and watchful waiting: - weight loss - reduce caffeine - avoid constipation
- Bothersome symptoms:
Drugs
- alpha-adrenergic antagonists- Target a1A receptor and lead to muscle relaxation
e.g. Tamsulosin, alfuzosin, doxazosin
- 5-alpha-reductase inhibitors - prevent conversion of testosterone to dihydrotestosterone (promotes growth and enlargement). Leads to shrinkage and improves obstructive symptoms. Given for large prostates >30g
e.g. Finasteride, Dustasteride - Surgery
- TURP = transurethral resection of the prostate - cystoscope placed inside urethra and prostate tissue shaved away. Makes adequate channel for urine flow
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 referred to as OAB - overactive bladder) = the complaint of an involuntary leakage accompanied by or immediately preceded by urgency
Mixed urinary incontinence =
More than 1 type. Seen in older patients
Continuous incontinence = continuous leakage (could be suggestive of vesicovaginal fistula, ectopic ureter (from kidney to urethra or vagina))
Overflow incontinence =
leakage when bladder is full, associated with chronic urinary retention secondary to obstruction or atonic bladder
Functional incontinence=
due to severe cognitive impairment or mobility limitations, preventing use of toilet. Bladder function is normal
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 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
Can affect 40% of women, more common in older women (1/5 women have some degree of SI)
What are the conservative / non-surgical interventions for SUI/SI?
Lifestyle changes
- Weight loss
- Cessation of smoking
- Modification of high/low fluid intake
- Decreased physical exertion
Supervised pelvic floor exercises - patients that try to do them alone often don’t do them correctly
What are the medical / pharmacological options for SUI/SI?
Duloxetine- inc. norepinephrine and serotonin (SNRIs) to increase urethral sphincter contraction
Oestrogen
What are the surgical options for SUI/SI?
Periurethral bulking agents - agent around urethra to cause physical obstruction (alternative to surgery)
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
Mid-urethral sling - prevents too much movement of the urethra and supports urethral sphincter
Colposuspension- stitches either side of bladder opening to stop it from moving when exerting
What does the female genitourinary system include?
composed of 2 kidneys, 2 ureters, urinary bladder and urethra.
What is the anatomy of the ureters?
25cm long, upper half lies in abdomen and lower half in pelvis.
3mm in diameter but slightly constricted at 3 places (pelvic ureteric junction, pelvic brim, as it passes through the bladder wall).
Ureters 3 layers of tissue-outer fibrous tissue, middle muscle layer and inner epithelium layer.
What supplies blood to the female ureters?
related to region: renal/lumbar/gonadal/common iliac, internal iliac and superior vesical arteries with corresponding venous drainage.
What is the lymphatic drainage of the female ureters?
left ureter drains into left para-aortic nodes, right ureter drains into right paracaval and interaortocaval lymph nodes
What is the nerve supply to the female ureters?
Autonomic nervous system
How does bladder anatomy change in a female?
When empty, bladder is pelvic organ, when distended it rises up to abdominal cavity and becomes an abdomino-pelvic organ.
What is the anatomy of the female bladder?
An empty bladder is a 4 sided pyramid in shape and has 4 angles: apex, neck and 2 lateral angles
4 surfaces: base/posterior surface, 2 inferiolateral surfaces and a superior surface.
Has 3 layers: outer loose connective tissue, middle smooth muscle and elastic fibres and inner layer lined with transitional epithelium.
What is the blood supply to the female bladder?
superior and inferior vesical branches of internal iliac artery
What is the venous drainage of the female bladder?
Drained by vesical plexus which drains into internal iliac vein
What is the lymphatic supply of the female bladder?
internal iliac nodes and then paraaortic nodes
What is the nerve supply to the bladder?
Autonomic nervous system
What is the anatomy of the female urethra?
channel from neck of bladder (internal urethral sphincter-detrusor muscle thickened, smooth muscle, involuntary control) to the exterior, at the external urethral orifice (external urethral sphincter-skeletal muscle, voluntary control).
Measures 3-4cm long
What is the blood supply to the female urethra and venous drainage?
internal pudendal arteries and inferior vesical branches of the vaginal arteries with corresponding venous drainage.
What is the lymphatic system of the female urethra?
proximal urethra into internal iliac nodes, distal urethra to superficial inguinal lymph nodes
What is the nerve supply of the female urethra?
vesical plexus and the pudendal nerve
What makes up the male GU system?
composed of 2 kidneys, 2 ureters, urinary bladder, prostate and urethra.
What is venous drainage of the male bladder?
by prostatic venous plexus which drains into internal iliac vein
What is the anatomy of the prostate?
Gland lying below the bladder in the male and surrounds the proximal part of the urethra (prostatic urethra)
Measures 4x3x2cm, conical in shape. Connected to bladder by connective tissue.
Has 3 parts-left lateral lobe, right lateral lobe and middle lobe.
What is the anatomy of the male urethra?
20 cm long, runs through neck of bladder, the prostate gland, the floor of pelvis and the perineal membrane to the penis and external urethral orifice at the tip of the male penis
Has 3 parts: prostastic, membranous and spongy urethra
What is the blood supply to the male urethra?
prostatic-inferior vesical artery, membranous-bulbourethral artery and spongy urethra-internal pudendal artery with corresponding venous drainage.
What is the lymphatics of the male urethra?
prostatic and membranous urethra drain to obturator and internal iliac nodes, spongy urethra drains to deep and superficial inguinal nodes
What is the nerve supply of the male urethra?
Prostatic plexus
What are the 2 phases of normal micturition?
Filling phase: bladder fills and distends without rise in intravesical pressure. Urethral sphincter contracts and closes urethra
Voiding phase: bladder contracts and expels urine, urethral sphincter relaxes and urethra opens
How is micturition different in adults and young children?
In infants micturition is a local spinal reflex in which bladder empties on reaching a critical pressure.
In adults voiding can be initiated or inhabited by higher centre control of the external urethral sphincter keeping it closed until it is appropriate to urinate
Describe the innervation of micturition?
The M3 receptors (parasympathetic S2-S4) are stimulated as the bladder fills.
As they become stretched and stimulated this results in contraction of the detrusor muscle for urination.
At the same time the parasympathetic fibres inhibit the internal urethral sphincter which causes relaxation and allows for bladder emptying.
When the bladder empties of urine the stretch fibres become inactivated, and the sympathetic nervous system (originating from T11-L2) is stimulated to activate the beta 3 receptors causing relaxation of the detrusor muscle allowing the bladder to fill again.
What are risk factors of urinary incontinence?
Ageing Obesity Smoking Pregnancy Route of delivery
What is the pathology behind SUI?
impaired bladder and urethral support and impaired urethral closure
What are investigations for SUI?
History
Examination (atrophy, prolapse, masses, sensation)
Empty supine stress test (demonstrate loss of urine on examination)
Post-void residual
Urinalysis (infection, diabetes)
Urodynamics ( urinary leakage during increased intra-abdo pressure in absence of detrusor contraction)
What is an overactive bladder? What is the epidemiology?
AKA. urge urinary incontinence
urinary urgency, usually with urinary frequency and nocturia, with or without urgency urinary incontinence
Overall prevalence of 16.6% in men and women over 40
What are risk factors of urge urinary incontinence?
Age Prolapse High BMI IBS/ constipation Bladder irritants (caffeine, nicotine)
What is the pathology of urge urinary incontinence?
not well understood. Involuntary detrusor (bladder wall) muscle contractions. Cause can be idiopathic, neurogenic (loss of central nervous system inhibitory pathways) or bladder outlet obstruction
What are symptoms and signs of an overactive bladder?
urgency, frequency, nocturia and urgency incontinence, impact on QOL-sleep disorders, anxiety and depression.
Assess for enlarge prostate in males and prolapse in women
What are investigations for urge urinary incontinence?
- History and examination
- Urine dipstick = check for infection
- Flow rate and PVR (post void residual) - empty bladder then look at bladder using USS. Should be <100ml
- Urodynamics (After conservative approach)
- Voiding diaries
- Cystoscopy
What is management for an overactive bladder?
- Behavioral/lifestyle changes:
- weight loss
- caffeine reduction
- fluid management
- smoking cessation
Bladder retraining and pelvic floor exercises - Drugs:
- Antimuscarinic drugs (inhibits ACh at M3 receptors and causes detrusor relaxation)
- Beta-3 agonists (cause relaxation of detrusor)
- BOTOX (blocks neuromuscular function of detrusor. Works for 6-9 months. Risk of retention in long term use) - Neuromodulation (PTNS/SNS)- stimulate tibial nerve or S3- deliver impulses and control bladder function
- Surgery:
- Augmentation cystoplasty (makes bladder larger by cutting bladder and stitching bowel on top)
- urinary diversion (appendix attached to bladder and skin- empty bladder through stoma using catheter)
What is the incidence of BPH?
Increases with age
50-60% males in 60’s
80- 90% males over 70
What are risk factors of BPH?
Hormonal effects of testosterone
What are signs and symptoms of BPH?
Hesitancy in starting urination Poor stream Dribbling post-micturition Frequency, nocturia Acute retention
What are causes of overflow incontinence?
Outlet obstruction (faecal impaction/BPH)
Underactive detrusor muscle
Bladder neck stricture
Urethral stricture
DHx-alpha adrenergics, anticholinergics, sedative
Bladder denervation following surgery
When someone presents with BPH whats the first thing you need to do?
Exclude other causes for above symptoms Abdominal, pelvic and rectal examination (urethra/bladder/rectum/prostate/sphincter)
What are differentials of BPH?
Bladder/prostate cancer Cauda equina High pressure chronic retention Urinary tract infections/sexually transmitted infections Prostatitis Neurogenic bladder (can be secondary to Parkinson's, Multiple sclerosis, etc.) Urinary tract stones (bladder stones) Urethral stricture
What are complications of BPH?
progressive bladder distention, causing chronic painless retention and overflow incontinence. If undetected can lead to bilateral upper tract obstruction and renal impairment, with patient presenting with chronic renal disease
