Benign Prostatic Hyperplasia — SAQ

Stem

A 68-year-old man presents with a 1-year history of worsening urinary frequency (8 times daily), nocturia (4 times per night), hesitancy, weak stream, and a sensation of incomplete emptying. DRE reveals a smooth, symmetrically enlarged, rubbery prostate. PSA is 2.8 ng/mL. IPSS is 16.^[1][2]

Questions

a) What is the diagnosis, and what features of the DRE support it? (2 marks)^[1][2]

Diagnosis: Benign prostatic hyperplasia with moderate LUTS (IPSS 16 = moderate, 8-19 range).^[1][2] DRE features supporting BPH: smooth, symmetrically enlarged, rubbery/firm consistency with preserved median sulcus. (Cancer would be hard, irregular, craggy, with loss of sulcus.)^[1][2]

b) What is the initial medical management and the mechanism of each drug? (3 marks)^[1][2]

1. Tamsulosin 0.4 mg OD (alpha-1a adrenergic blocker) — relaxes smooth muscle in the prostate and bladder neck (dynamic component). Rapid onset (days to weeks).^[1][2]
2. Finasteride 5 mg OD (5-alpha-reductase inhibitor) — blocks conversion of testosterone to DHT, causing prostate shrinkage over 6 months (static component). Reduces prostate volume by about 19 percent at 12 months (the original randomised trial).^[1][3]
3. Combination therapy is appropriate (prostate is enlarged). MTOPS trial: combination superior to either alone for progression prevention.^[1][2]

c) The patient undergoes TURP and 45 minutes into the procedure develops confusion and bradycardia. Sodium is 121 mmol/L. What has happened and how do you manage it? (3 marks)^[1][2]

TURP syndrome — dilutional hyponatraemia from absorption of glycine irrigation fluid through open prostatic venous sinuses.^[1][2] Management:

1. Stop surgery immediately.
2. Furosemide (diuretic to promote fluid excretion).
3. Hypertonic saline for severe hyponatraemia with neurological symptoms (the TUR-syndrome series defines the severe state as sodium at or under 125 mmol/L; the saline strength and furosemide are local-protocol conventions).^[1][2]
4. Prevention: limit resection time, use bipolar TURP (saline irrigation) or HoLEP.^[1][2]

d) What is the commonest complication of TURP that should be discussed pre-operatively? (2 marks)^[1][2]

Retrograde ejaculation (the commonest TURP complication; 65-75% is the classic textbook range) — semen travels backward into the bladder during orgasm because the bladder neck has been resected. Not harmful but affects fertility. Must be explicitly discussed during consent.^[1][2]

References3ShowHide

1. [1]Lerner LB, McVary KT, Barry MJ, et al. Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA Guideline J Urol, 2021.PMID 34384237
2. [2]McConnell JD, Roehrborn CG, Bautista OM, et al. The long-term effect of doxazosin, finasteride, and combination therapy on the clinical progression of benign prostatic hyperplasia N Engl J Med, 2003.PMID 14681504
3. [3]McConnell JD, Bruskewitz R, Walsh P, et al. The effect of finasteride on the risk of acute urinary retention and the need for surgical treatment among men with benign prostatic hyperplasia N Engl J Med, 1998.PMID 9475762