Benign Prostatic Hyperplasia Flashcards
Define benign prostatic hyperplasia
Slowly progressive nodular or diffuse hyperplasia of the periurethral (transitional) zone of the prostate gland
ie benign growth
Predominantly due to 2 components:
- Static: increase in benign prostatic tissue → narrowing of urethral lumen
- Dynamic: increase in prostatic smooth muscle tone mediated by alpha-adrenergic receptors.
Differentiate between area of growth in BPH versus prostate carcinoma
The inner transitional zone enlarges in BPH
- The transition zone (TZ) surrounds the urethra as it enters the prostate gland.
- It is small in young adults, but it grows throughout life, taking up a bigger percentage of the gland
The peripheral zone enlarges in prostate carcinoma
- Contains the majority of prostatic glandular tissue.
- The largest area of the peripheral zone is at the back of the gland, closest to the rectal wall.
- Hence on DRE can be felt
Explain the risk factors for benign prostatic hyperplasia
-
age over 50 years
- age-related hormonal changes create androgen/oestrogen imbalances.
- Changes in prostatic stromal-epithelial interactions that occur with ageing and increases in prostatic stem cell numbers
- positive family history
- non-Asian race
- cigarette smoking
Summarise the epidemiology of benign prostatic hyperplasia
COMMON:
- 42% of men 51-60 years
- 82% of men 71-80 years
- global lifetime prevalence of BPH is around 25%
More common in the west than the east
More common in Afro-Caribbeans
Recognise the presenting symptoms of benign prostatic hyperplasia
Can be divided into 2 categories:
Storage symptoms
- Frequency
- Urgency
- Nocturia
Voiding symptoms
- Weak stream
- Hesitancy
- Intermittency
- Straining
- Incomplete emptying
- Post-void dribbling
What is an acute complication of BPH?
Urinary retention
- Sudden inability to pass urine
- Associated with SEVERE PAIN
What is a symptom of a complication of BPH?
UTI
- Fever with dysuria
- Smell/odour
What are the symptoms of chronic retention?
- Painless
- Frequency - with passage of small volumes of urine
- Nocturia is a major feature
Recognise the signs of benign prostatic hyperplasia on physical examination
DRE -
- the prostate is usually smoothly enlarged with a palpable midline groove
- there is poor correlation between the size and the severity of the symptoms
Signs of Acute Retention
- Suprapubic pain
- Distended, palpable bladder
Signs of Chronic Retention
- A large distended painless bladder (volume > 1 L)
- Signs of renal failure
Identify appropriate investigations for benign prostatic hyperplasia
Urinalysis
- Check for UTI signs and blood
Bloods
- U&Es - check for impaired renal function
- PSA- increased PSA may suggest the presence of underlying prostate cancer or prostatitis.
Urinalysis
- MC&S
- normal in uncomplicated BPH; pyuria may indicate UTI
- haematuria might indicate cancer
- Uroflowmetry- measure of peak urinary flow rate. <15ml/s in moderate-to-severe BPH.
Imaging
Patients with chronic retention, history of urinary tract surgery, recurrent urinary tract infections or haematuria, presence of urolithiasis, or renal insufficiency.
-
US of urinary tract - check for:
- hydronephrosis
- mass
- urolithiasis
- post-void residual
- Bladder scanning to measure pre- and postvoiding volumes
- Transrectal Ultrasound Scan (TRUS) - allows assessment of bladder size and volume - +/- biopsy
-
Flexible Cystoscopy-
- indicated in patients for direct visualisation or intervention as indicated, following urinary tract imaging.
- may show mass/stone/stricture
International prostate symptom score
- Mild score: 0 to 7
- Moderate score: 8 to 19
- Severe score: 20 to 35
- Also includes an additional question on quality of life (bother score) scored from 0 to 6.
Generate a management plan for benign prostatic hyperplasia
In Emergency (acute urinary retention)
- Catheterisation
Conservative (if mild)
- Watchful waiting
- Lifestyle: avoid caffeine, alcohol to reduce urgency. Relax when voiding and control urgency by practising distracting exercises.
Medical – useful when waiting for surgery
-
Selective a-blockers (e.g. tamsulosin) are 1st line -
- relax the smooth muscle of the internal urinary sphincter and prostate capsule
- May cause ED and increased fall and fracture risk
-
5a-reductase inhibitors (e.g. finasteride)
- Larger prostate >30g/symptom progression on a-blockers
- inhibit the conversion of testosterone to dihydrotestosterone
- reduce prostate size by around 20%
- Excreted in semen so should use condom.
Surgery
- TURP: transurethral resection of prostate
- TUIP: transurethral incision of prostate – less destruction so less risk to sexual function but gives smaller benefit
- Open prostatectomy- significantly enlarged prostates (typically ≥80 grams)
Identify possible complications of benign prostatic hyperplasia
SHORT TERM
- BPH progression- 20% in 5 years
- urinary tract infection (UTI)
- renal insufficiency
- bladder stones- secondary to urinary stasis.
- haematuria- secondary to any urinary pathology and/or haematological disorders.
- sexual dysfunction- 5-8% with alpha blockade and 10-15% with 5-alpha-reductase inhibitor or surgical management.
LONG TERM
- acute or chronic urinary retention- significant reduction in urethral lumen diameter and increased sympathetic tone contribute to acute retention
- overactive bladder- treatment with alpha-blockers and antimuscarinic agents to aid symptoms
Summarise the prognosis for patients with benign prostatic hyperplasia
- The majority of patients with BPH can expect at least moderate improvement of their symptoms
- Lower urinary tract symptoms and medical/surgical therapy may affect sexual wellbeing including erectile function.
- Mild symptoms are usually well controlled medically
- Most patients get significant relief from surgery
