Benign Prostatic Hyperplasia (BPH)

See Prostate Cancer & PSA Screening for the malignant differential.

BPH is strictly a histological diagnosis and shouldn’t be used loosely to describe lower urinary tract symptoms (LUTS) — it is simply the most common cause of bladder outlet obstruction (BOO). Bladder neck obstruction and urethral sphincter spasm are other, less common causes of the same symptom picture.

BPH is extremely common with age: histological prevalence reaches 50–60% of men in their 60s and 80–90% of men over 70. Other differentials for LUTS in men include urinary tract infection, prostatitis, bladder calculi, interstitial cystitis, urethral stricture, overactive bladder, prostate or bladder cancer, and neurological conditions (Parkinson disease, stroke, spinal cord disease) or nocturnal polyuria/sleep apnoea when storage symptoms predominate.

Presentation

Voiding (bladder emptying) symptoms: hesitancy, slow/interrupted stream, terminal dribbling, incomplete emptying, straining.

Storage (bladder filling) symptoms: frequency, urgency, nocturia.

Murtagh’s triad: poor urine flow + straining to void + frequency → suspect BOO.

Acute retention, retention with overflow incontinence, and haematuria from ruptured submucosal prostatic veins can all occur. Use the International Prostate Symptom Score (IPSS) to quantify bother and track response to treatment.

Red flags for urology referral: haematuria, incontinence, urinary retention, recurrent UTI, bladder calculus, renal impairment, hydronephrosis, large bladder diverticulum, symptoms refractory to medical management.

Examination and investigations

• Abdominal exam: exclude a palpable bladder.
• Genital exam: exclude phimosis, meatal stenosis, or other obstructing pathology.
• DRE: assess prostate size; exclude a hard/nodular/asymmetric gland suggestive of cancer, or tenderness suggestive of prostatitis; assess for constipation.
• Urinalysis: exclude leucocytosis, haematuria, proteinuria, pyuria, glucosuria.
• Bloods: eGFR (exclude renal impairment from BOO or intrinsic renal disease); PSA (controversial in this context but useful to help exclude/flag concurrent cancer risk — see Prostate Cancer & PSA Screening). The RACGP recommends against routine PSA screening, but PCFA/Cancer Council Australia guidelines (supported by USANZ) recommend offering PSA testing every 2 years to average-risk men aged 50–69 who want it.
• Urinary tract ultrasound: prostate volume, bladder wall changes, post-void residual.
• Voiding diary: helpful if polyuria is suspected (> 3L/24h, or nocturnal polyuria > 1/3 of 24-hour output).
• Urodynamic studies: specialist-directed, reserved for diagnostic uncertainty.

Management

Lifestyle/behavioural (first-line for mild symptoms): reduce evening fluid intake, bladder irritants (caffeine, alcohol, carbonated/spicy foods) and constipation; avoid over-the-counter cold/cough preparations containing alpha-agonists (they worsen obstruction); bladder training, pelvic floor exercises, double voiding; stay active.

Medical therapy:

• Alpha-1 blockers (tamsulosin, alfuzosin, silodosin — uroselective, less blood-pressure effect; prazosin is non-selective and needs twice-daily dosing with more BP effect): relax smooth muscle in the prostate and bladder neck. Side effects: retrograde ejaculation, erectile dysfunction, nasal congestion, hypotension, dizziness. Caution before cataract surgery — risk of intraoperative floppy iris syndrome.
• 5-alpha-reductase inhibitors (finasteride, dutasteride): reduce prostate volume over months by blocking testosterone-to-DHT conversion; generally reserved for prostates > 30–40mL, often combined with an alpha-blocker (e.g. Duodart = dutasteride + tamsulosin, PBS-subsidised as a single combination product). Side effects: erectile dysfunction, decreased libido/ejaculate volume, breast tenderness/enlargement. Takes up to 6 months for full effect and can lower PSA by around 50% — a rising PSA in a man on a 5-alpha-reductase inhibitor needs earlier urology review, not reassurance from a still-”normal” absolute value. Pregnant women should avoid handling the tablets (risk of feminisation of a male fetus).
• Combination therapy (alpha-blocker + 5-alpha-reductase inhibitor) outperforms either drug alone for reducing progression, urinary retention, and need for surgery — most clearly in men with prostate volume >40mL and PSA >1.5.

Surgical: TURP remains the gold-standard surgical treatment for symptomatic BPH; open prostatectomy is now rare (<1%). Newer minimally invasive options — water vapour thermal therapy (Rezum), prostatic urethral lift (UroLift, TGA-approved since 2012 — patients are often catheter-free at discharge with ejaculatory function preserved), and aquablation — have emerged as alternatives to TURP for selected patients wanting to preserve ejaculatory function, though TURP remains the benchmark for durability of symptom relief. UroLift is unsuitable for prostates >80mL, an obstructing median lobe, or urinary retention.

Referral to urology: urinary retention, hydronephrosis on ultrasound, symptoms refractory to medical management, recurrent UTIs, gross haematuria, bladder stones, renal insufficiency, incontinence, or a large bladder diverticulum.

Bladder neck stenosis and urethral stricture

Also cause voiding dysfunction and can complicate any treatment for prostate cancer or BPH. If obstructive symptoms recur or begin soon after a prostate procedure, suspect a developing stricture — most respond to simple endoscopic management.