Clinical FeaturesMen’s HealthUrology

Benign Prostatic Hyperplasia (BPH)

Written by Dr Stefanie Croghan – Specialist Registrar in Urology and Mr James Forde – Consultant Urologist

Background and Definition

The prostate gland is located just inferior to the bladder, and typically approximates the size of a walnut or chestnut in young adult men, weighing 18-20g. 1,2 It is composed of a combination of fibromuscular stroma and glandular elements, and serves in the production and liquefaction of the ejaculate. 1 Benign prostatic hyperplasia (BPH) refers to a non-malignant process resulting in enlargement of the prostate gland (Figure 1).


BPH is an extremely common process. Figures quote prevalence (on pathological inspection) of ~50% in men aged >50 years and >80% in men aged >70. 3

Pathophysiology & Risk Factors

BPH results from an increase in the number of epithelial and stromal cells in the region of the prostate surrounding the urethra. 4 The enlarged prostate may exert an obstructive effect on the urethra via both dynamic (contraction of prostatic smooth muscle) and static (direct local influence of increased volume) effects. 5

Both prostatic enlargement and consequent lower urinary tract symptoms increase with age; prostate volume has been observed to increase at a rate of 0.6ml [-9.9-62.1ml] per year in one longitudinal study. 6,7 The interplay of further potential risk factors is incompletely understood, however obesity, hypertension, obesity, diabetes, diets lacking in fruit, vegetables and fibre and sex hormone levels have been implicated in the development of BPH. 8

Clinical Consequences

BPH may be asymptomatic, or may result in bladder outlet obstruction, causing lower urinary tract symptoms (LUTS) or urinary retention, which may be acute or chronic. 5,8 Chronic urinary retention risks increased bladder pressure with transmission to the upper urinary tracts, causing hydronephrosis and renal impairment. In addition, high residual volumes of urine within the bladder predispose a patient to urinary tract infections, which may progress to epididymoorchitis or pyelonephritis. 5,8


Patients may present with a variety of lower urinary tract symptoms, including a weak stream of urine, straining to void, intermittency of the urinary stream, a feeling of incomplete bladder emptying, urinary frequency and urinary urgency. The extent of these symptoms and their impact on a patient’s quality of life may be quantified using the validated International Prostate Symptom Score (IPSS). 9

Haematuria may occur, but must be fully investigated for other causes before being ascribed to BPH. The presence of nocturnal enuresis (bed-wetting) is a sign of high-pressure chronic retention, and should be enquired about. The presence of neurological symptoms may suggest a non-prostatic cause of LUTS. Clinical history taking should seek the presence of medical conditions that may contribute towards LUTS (e.g. diabetes/other endocrine disorders or diuretic requirements) or influence treatment options. In addition, lifestyle factors should be explored, in particular fluid and caffeine intake. 5,10,11

Physical Examination

A physical examination should be performed on male patients presenting with LUTS/suspected BPH. This should include suprapubic palpation (assessing for a distended bladder), penile examination (for penile lesions, meatal stenosis or a tight phimosis – potential causes of LUTS) and a neurological examination of the lower limbs. A digital rectal exam (DRE) should be performed to estimate prostatic size and to assess the surface contour and consistency of the palpable peripheral zone of the prostate, with firm/hard regions or nodules raising possibility of malignancy. 8,12

Further Diagnostic Assessment

Urinalysis can be performed at the time of the physical examination and is important to detect urinary tract infection, non-visible haematuria or evidence of renal dysfunction. 12 Bloods should be taken for a renal profile. A prostate specific antigen (PSA) test may be considered at this time. PSA serves as a screening tool for prostate cancer and may also have some role in predicting prostatic volume; 13 however patients should be counselled regarding the implications of PSA testing, and given the option to choose whether or not to proceed. 8,12,14 Post-void residual volume (PVR) assessments (bladder scans) are imperative to evaluate for incomplete bladder emptying, with high volumes prompting the need for immediate catheterisation. Within urology services, uroflowmetry will be performed, which plots the velocity of urinary stream over time on a graph and can suggest potential obstruction. 8 Cystourethroscopy may be required for a variety of reasons including the presence of haematuria or suspicion of a urethral stricture, and cystometrogram may be indicated for non-straightforward cases of male LUTS (such as young age, equivocal findings on uroflowmetry, the presence of a neurological condition, a history of prior radical pelvic surgery or prior surgical intervention for BPH). 5,8,12 Renal ultrasonography or alternative upper tract imaging is indicated in the presence of abnormal renal function or for other indications (haematuria, suspected calculi) but is not routine in the evaluation of LUTS. 12

Management Options

A number of management options exist for patients with BPH. 5,8,12

i. Conservative

Patients with mild or moderate symptoms and minimal bother may be observed.

They should be advised about lifestyle measures that may exacerbate LUTS or increase the risk of acute urinary retention (nocturnal fluid intake, caffeine, alcohol, constipation and overthe-counter nasal decongestants). Patients should be advised of the risk of BPH progression; a 4 year longitudinal study of 400 men found approximately 1/3 to have experienced clinical progression and approximately 5% to have had an episode of acute urinary retention over the study period. 15

ii. Medical

  • α1-adrenergic antagonists aim to cause relaxation of prostatic smooth muscle and the bladder neck, by blockade of α1 receptors located within. Tamsulosin is the best known of these; Silodosin has been shown to exert more selectivity for α1A adrenoreceptors versus α1B adrenoceptors and may reduce the risk of postural hypotension in susceptible patients. 16,17 The main adverse effect is retrograde ejaculation.
  • Although less frequently prescribed for LUTS, phosphodiesterase type 5 inhibitors such as Sildenafil cause smooth muscle relaxation. Regular use can result in an improvement of lower urinary tract symptoms in men with or without erectile dysfunction. 18
  • Another drug class is steroid 5α-reductase inhibitors (5ARIs), with examples of which are Finasteride and Dutasteride. These may be prescribed alone or in combination with an α1-adrenergic antagonists. 5ARIs block the conversion of testosterone to Dihydrotestosterone (DHT), with resultant shrinkage of the prostate. These drugs must be taken for 4–6 weeks for benefit to emerge, and 3–6 months of treatment are required for full efficacy. 12 They are generally well tolerated, however possible adverse effects include loss of libido, sexual dysfunction and mood alteration. Whilst these generally resolve on drug cessation, there is emerging evidence that they may persist in a very small minority. 19

Bladder outlet obstruction, particularly over time, can result in the bladder becoming unstable and causing symptoms of bladder overactivity. Men with these symptoms and low post-void residual volumes may benefit from the addition of muscarinic receptor antagonists of muscarinic receptor antagonists (e.g. Solifenacin, Tolterodine, Fesoterodine) or beta-3 adrenergic agonists (e.g. Mirabegron) alongside medications targeting outlet obstruction can provide relief. This may increase the chance of urinary retention, but the risk appears low.

iii. Surgical / Interventional

A number of surgical treatments exist for the management of symptomatic BPH.

  • The most frequently performed of these is surgical debulking of the adenoma. This may be performed via monopolar or bipolar electrocautery transurethral resection of the prostate (TURP) or using other technologies, such as LASER or water vapourisation. A more conservative modification, transurethral incision of the prostate (TUIP) which aims to widen the bladder outflow tract without the removal of tissue, may be suitable for a small subgroup of patients. 8
  • Urethral lift is a minimally invasive procedure that may be performed as a day-case and involves placement of small implants to compress or ‘lift’ the prostate away from the urethra and improve urinary flow. As a relatively new procedure, data on longterm outcomes are still somewhat lacking. A main advantage, however, is a lower rate of ejaculatory dysfunction as compared to other treatments. 8,21
  • Enucleation or adenectomy, the removal of all prostatic tissue off its capsule is another surgical option, generally reserved for very large prostates. This may be performed by open or minimally-invasive prostatectomy or transurethral laser enucleation. 8

iv. Interventional Radiological

  • Prostatic artery emobolization (PAE) involves selective embolization of the prostate’s arterial blood supply, with the aim of resultant tissue necrosis and shrinkage of the gland. Objective outcome data regarding efficacy are lacking compared to alternative treatments and it is uncommonly performed in Ireland. It may have some role in patients with large, vascular prostates who require a minimally invasive approach that does not require general anaesthesia. 8,22

v. Catheterisation

A final option, for patients with bothersome LUTS, high post void residual volumes or recurrent urinary retention, who have not benefitted from, have a preference to avoid, or are medically high-risk for, alternative treatment strategies is to have a long-term indwelling urethral catheter or to be educated in intermittent self-catheterisation. 5


BPH is a common condition affecting men and increases in prevalence with age. It may be asymptomatic or cause bladder outlet obstruction and related symptoms. The greatest risks are of acute urinary retention, urological infections and high pressure chronic urinary retention, which can result in irreversible renal impairment if undiagnosed. Initial assessment includes examination of the external genitalia and a DRE, urinalysis, biochemical renal profile, postvoid residual volume measurement and uroflowmetry and, in addition, PSA in counselled patients wishing to proceed. Management options include observation, pharmacological treatment, surgery, and for a minority of patients, long-term catheterisation or intermittent self-catheterisation.

References on request

Read the latest edition of Hospital Professional News: August HPN

Catch up on our Clinical Features

Leave a Reply

Your email address will not be published. Required fields are marked *

Please Confirm

This website is only for the eyes of medical professionals. Are you a medical professional?