LOWER URINARY TRACT SYMPTOMS
A 71-year-old man has been referred to the urology outpatient clinic with a history of urinary frequency, nocturia and some post-micturition dribbling. He has occasional urgency. He suffers with osteoarthritis of his left hip and uses a walking stick. He has angina, hypertension and hypercholesteraemia. He is an ex-smoker and lives with his wife. His younger brother had prostate cancer and underwent a radical prostatectomy at the age of 65 years. He is anxious to get his prostate-specific antigen (PSA) tested as he is concerned about prostate cancer.
Abdominal examination is unremarkable. The bladder is not palpable and the genitalia are normal with no evidence of stenosis of the urethral meatus or phimosis. Digital rectal examination confirms a moderately enlarged smooth prostate gland.
• What are the causes of an elevated PSA?
• How would you classify this patient’s symptoms?
• What is the likely diagnosis in this patient?
• What treatment would you recommend?
Prostate-specific antigen is a glycoprotein enzyme produced by the prostate gland. Its function is to liquefy the ejaculate and to aid sperm motility. In symptomless men appropriate counselling is required prior to performing a PSA blood test. A raised PSA may be caused by benign prostatic hyperplasia (BPH), prostatitis, urinary tract infection, urinary retention,
instrumentation (e.g. catheterization), biopsy, a transurethral resection of the prostate (TURP) or by prostate cancer. Prostate cancer screening is not currently of proven benefit,although several trials are investigating its value at present. PSA values vary with age,reflecting the effect of BPH on the prostate gland. Normal ranges are outlined.
This patient has lower urinary tract symptoms (LUTS) which are classically divided into two groups:
• obstructive: weakness of urinary stream, hesitancy, terminal dribbling, intermittency,feeling of incomplete bladder emptying
• irritative: urinary urgency, frequency, nocturia and incontinence.
Patients with bladder outflow obstruction may present with obstructive symptoms alone or in conjunction with irritative symptoms. The irritative symptoms are secondary to the obstruction which leads to changes in the bladder causing bladder overactivity. In this case the patient has LUTS secondary to BPH. Organizing a PSA for LUTS alone is reasonable, but in this case the patient has other risk factors – family history and his age. Other indications to organize a PSA blood test include an abnormal digital rectal examination,progressive back pain, unexplained weight loss and prostate cancer monitoring.
Baseline LUTS can be measured using the International Prostate Symptom Score (IPSS;range 0–35), a symptom index questionnaire. This is useful in monitoring the response to treatment. In this case he has moderate symptoms. Other factors that point to the diagnosis of BPH include his low maximal flow rate (normal in males 30 mL/s; females40 mL/s) and his elevated post-micturition residual volume, which indicates incomplete bladder emptying (another feature of significant bladder outflow obstruction).
Treatment options include watchful waiting (periodic monitoring, lifestyle advice), medical therapy (alpha-blockers and/or 5-alpha reductase inhibitors) and surgery (TURP)
• The serum PSA may be raised in benign disease.
• Patients should be counselled prior to PSA testing.