Benign Prostatic Hyperplasia (BPH)
Summary
Benign Prostatic Hyperplasia (BPH) is the non-malignant proliferation of the epithelial and stromal cells of the prostate gland. It is an almost distinctive feature of aging in men. Clinically, it results in Benign Prostatic Enlargement (BPE) which can cause Bladder Outflow Obstruction (BOO) leading to Lower Urinary Tract Symptoms (LUTS). Management is determined by the "bother" score and risk of progression. Options range from Watchful Waiting to Pharmacotherapy (Tamsulosin/Finasteride) and Surgery (TURP/HoLEP). [1,2]
Clinical Pearls
High Pressure Chronic Retention (HPCR): This is a silent kidney killer. The patient has a huge bladder (>1 litre) but NO PAIN (desensitised). The back pressure is transmitted up the ureters, causing bilateral Hydronephrosis and Renal Failure. NEVER decompress these patients rapidly or disappear. They are at risk of Post-Obstructive Diuresis (massive urine output >200ml/hr) which causes shock and electrolyte imbalance. Monitor input/output hourly.
PSA Rules: BPH raises PSA (approx 0.15 ng/mL per gram of tissue). Ejaculation can raise it for 48h. Cycling can raise it. UTI raises it massively (wait 6 weeks).
Floppy Iris Syndrome: Tamsulosin causes the iris to become floppy during Cataract Surgery, increasing complication rates. Always ask if a patient is undergoing eye surgery before starting an Alpha-blocker.
Demographics
- Prevalence: 50% of men at age 60; 90% of men at age 85.
- Race: More common and severe in African-American men.
- Diet: High metabolic syndrome / obesity is a risk factor.
Terminology
- BPH: Histological diagnosis (Hyperplasia of cells).
- BPE: Anatomical diagnosis (Dr can feel a big gland).
- BOO: Functional diagnosis (Flow rate is slow).
- LUTS: Clinical diagnosis (Patient complains of symptoms).
- Note: You can have BPH without LUTS, and LUTS without BPH.
Mechanism
- Hormonal Driver: Testosterone is converted to Dihydrotestosterone (DHT) by the enzyme 5-alpha-reductase (Type 2). DHT is 10x more potent than Testosterone.
- Hyperplasia: DHT binds to androgen receptors in the nuclei of stromal and epithelial cells, preventing apoptosis and driving growth factors.
- Location: Hyperplasia occurs almost exclusively in the Transition Zone (Peri-urethral). This is why it blocks flow early. (Cancer typically starts in the Peripheral Zone).
The Dual Obstruction
- Static Component: The sheer physical bulk of the adenoma squeezes the urethra.
- Dynamic Component: The stromal tissue is rich in Alpha-1 Adrenoceptors. Sympathetic tone keeps these muscle fibers tight, actively constricting the urethra.
| Condition | Distinguishing Factors |
|---|---|
| Prostate Cancer | Hard, craggy, irregular prostate. High PSA. |
| Urethral Stricture | History of trauma/catheter/STI. Poor flow but small prostate. |
| Overactive Bladder (OAB) | Urgency/Frequency predominate. Flow may be normal. |
| Neurogenic Bladder | History of Spinal cord injury, MS, Parkinson's. |
| Bladder Cancer | Haematuria + LUTS (CIS). |
| UTI | Dysuria, cloudy urine, nitrates positive. |
Lower Urinary Tract Symptoms (LUTS)
Divided into Voiding (Obstructive) and Storage (Irritative). Use the mnemonic FUN WISe.
Storage Symptoms (FUN) - Caused by Detrusor Overactivity:
Voiding Symptoms (WISe) - Caused by Obstruction:
Signs
Bedside
- IPSS Score (International Prostate Symptom Score): Validated questionnaire.
- Mild: 0-7.
- Moderate: 8-19.
- Severe: 20-35.
- Urine Dipstick: Exclude UTI and Haematuria (Red Flag).
- Frequency Volume Chart: Gold standard for Nocturia/Polyuria.
Laboratory
- U&Es: Creatinine (Rule out renal failure).
- PSA: Offer to informed men >50 (or >45 if risk factors). Use age-specific reference ranges.
Specialist
- Uroflowmetry: Patient urinates into a machine.
- Qmax (Max flow rate):
- >15 ml/s: Normal.
- less than 10 ml/s: Obstructed.
- Qmax (Max flow rate):
- Post Void Residual (PVR): Bladder scan. >100ml is significant.
- TRUS Biopsy / MRI: If cancer suspected.
Management Algorithm
DIAGNOSIS OF BPH
(LUTS + Enlarged Gland)
↓
ASSESS COMPLICATIONS
(Retention/Stones/Renal Failure)
NO ────────────┐ YES
↓ ↓
ASSESS IPSS SURGERY / CATHETER
(Score 0-35)
↓
┌──┴─────────────────────────┐
MILD (0-7) MODERATE/SEVERE
Bother Low (Or Bother High)
↓ ↓
WATCHFUL WAITING MEDICAL THERAPY
- Fluid advice (See Below)
- Caffeine reduction ↓
- Bladder drill FAILED MEDS?
↓
SURGICAL THERAPY
(TURP / HoLEP)
1. Medical Therapy
A. Alpha-Blockers (Tamsulosin, Alfuzosin)
- Mechanism: Relax smooth muscle in prostate/bladder neck (Dynamic component).
- Indication: First line for moderate LUTS.
- Onset: Fast (days).
- Side Effects: Dizziness (Postural hypotension), Retrograde Ejaculation ("Dry Orgasm").
B. 5-Alpha Reductase Inhibitors (5-ARI) (Finasteride, Dutasteride)
- Mechanism: Blocks T -> DHT conversion. Shrinks gland size by 20-30%.
- Indication: Large prostates (>40g). Prevention of progression.
- Onset: Slow (3-6 months).
- Side Effects: Erectile Dysfunction, Reduced Libido, Gynaecomastia.
- Note: Halves the PSA level (must double result to compare to normal range).
C. Combination Therapy (Combodart)
- Tamsulosin + Dutasteride. More effective than monotherapy for severe symptoms.
2. Surgical Therapy
Standard:
- TURP (Transurethral Resection of Prostate): The "Re-bore". Diathermy loop cuts chips of prostate away.
- Risks: Bleeding, Infection, Retrograde Ejaculation (75%), TUR Syndrome (Absorption of irrigation fluid -> Hyponatraemia).
- HoLEP (Holmium Laser Enucleation): Anatomical enucleation of the lobes. Better for massive glands (>100g). Less bleeding.
Minimally Invasive (MIST):
- UroLift: Implants that pin the lobes back like curtains. Preserves ejaculation.
- Rezum: Steam injection causing necrosis.
- PAE (Prostatic Artery Embolisation): Radiology procedure to block blood supply.
- Acute Urinary Retention (AUR): Painful. Requires catheterisation.
- Chronic Urinary Retention: Painless. Over-distended bladder.
- High Pressure: Causes Hydronephrosis and CKD.
- Bladder Stones: Stasis allows crystallisation.
- Haematuria: From friable varices on prostate.
- Recurrent UTIs.
- Untreated BPH is progressive.
- Medical therapy is effective for years but surgery is eventually required for 20-30%.
- TURP Success: Improves flow rate (Qmax) by 100-150% and IPSS by 70%.
Key Guidelines
| Guideline | Organisation | Key Recommendations |
|---|---|---|
| LUTS in Men | NICE CG97 (2010) | Alpha blockers 1st line. 5-ARI for big glands. |
| Non-neurogenic LUTS | EAU (2023) | Comprehensive review of MISTs (Urolift etc). |
Landmark Evidence
1. MTOPS Study (NEJM)
- Medical Therapy of Prostatic Symptoms. Showed that Combination Therapy (Alpha blocker + 5-ARI) significantly reduced the risk of clinical progression (retention/surgery) compared to either drug alone.
2. CombAT Study
- Confirmed combination therapy superiority specifically in men with large glands and high PSA.
What is the Prostate?
It is a small gland, usually the size of a walnut, that sits at the base of the bladder. Its job is to produce the fluid for sperm.
Why is it causing trouble?
As men age, the prostate naturally grows (like grey hair, it's a normal part of aging). Because the urine pipe (urethra) runs right through the middle of it, the growing gland squeezes the pipe. This makes it harder to pee.
Is it Cancer?
No. Benign means "not cancer". However, you can have both at the same time, so we often check a PSA blood test to be sure.
What are the treatments?
- Lifestyle: Drink less simply water/coffee, especially before bed.
- Tablets: One type relaxes the muscle (Tamsulosin) to open the pipe. Another type shrinks the gland (Finasteride).
- Surgery: If tablets don't work, we can surgically "rebore" the pipe to clear the blockage.
Primary Sources
- NICE. Lower urinary tract symptoms in men: management (CG97). 2010.
- McConnell JD, et al. The long-term effect of doxazosin, finasteride, and combination therapy on the clinical progression of benign prostatic hyperplasia (MTOPS). N Engl J Med. 2003.
- Roehrborn CG, et al. The effects of combination therapy with dutasteride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hyperplasia: 4-year results from the CombAT study. Eur Urol. 2010.
Common Exam Questions
- Safety: "Hyponatraemia post-TURP?"
- Answer: TUR Syndrome. Absorption of glycine irrigation fluid. (Modern Bipolar TURP uses Saline, reducing this risk).
- Pharmacology: "S/E of Finasteride?"
- Answer: Erectile Dysfunction, Gynaecomastia.
- Diagnosis: "DRE Findings?"
- Answer: Smooth, elastic, enlarged, median sulcus palpable.
- Emergency: "Large painful bladder?"
- Answer: Acute Retention. Catheterise immediately.
Viva Points
- PSA Counseling: Before checking PSA, you must counsel the patient. It is not specific. A high result might mean infection or big prostate, not cancer. It can lead to unnecessary biopsies and anxiety.
- High Pressure Retention: Why do we monitor urine output after catheterising chronic retention? To watch for Post Obstructive Diuresis. The kidneys have lost their concentrating ability and dump fluid. If usually >200ml/hr for 2 hours, they need IV fluid replacement to prevent shock.
Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists.