The incidence of BPH rises with age. It is estimated that 65% of men aged 60 have some urinary symptoms.
Causes of BPH
Enlargement of central part of the prostate (transition zone) narrows the calibre of the urethra passing through its middle and causes obstruction to the flow of urine from the bladder.
BPH Symptoms
‘Obstructive’ bladder symptoms include having to wait to get started, a poor urinary flow, and needing to strain to pass urine. In some patients, the back-pressure caused by the obstruction separates nerve endings from the bladder muscle fibres they are travelling towards, causing the bladder to behave in a reflex manner rather like a baby’s bladder does.
The ‘irritative’ symptoms caused by an unstable bladder include frequency (going often), urgency (going in a hurry) and urge incontinence (leaking if you can’t get to a toilet in time).
Other BPH symptoms relate to the stagnation of urine, which can lead to urinary infection (pain on and frequency of passing urine) or stone formation (recurrent urinary infections and frequency), and the symptoms of kidney failure, which is thankfully very rare.
Getting up at night once or twice to pass urine (‘nocturia’) becomes increasingly common with increasing age in both sexes as the kidneys make more urine at night. It is not necessarily a symptom of problems, although it can be bothersome.
Dribbling urine after the main stream has finished is common in middle-age and beyond and is also not necessarily a sign of prostate or bladder problems. It is due to pooling of urine in the ‘U’ bend of the urethra after it has left the bladder due to age-related weakness of the muscle (‘bulbospongiosus’) that surrounds that part of the urethra.
This is the same muscle that contracts to expel semen out of the urethra during climax. The solution is either to push a finger up behind the scrotum and run it forwards to milk the urine out of the urethra or simply to put some toilet tissue into your underwear.
BPH - Investigations
All patients with bothersome urinary symptoms should be investigated as the severity of
BPH symptoms does not always reflect the severity of the problem.
Urine sample
This is taken to look for the presence of blood or inflammatory cells in the urine and to exclude infection.
Blood tests
These specifically investigate the health of the kidneys and the prostate.
Prostate-specific antigen (PSA) is a chemical which is only produced by prostate cells (hence ‘prostate-specific’) and which is detectable in the blood. A number of factors cause its increased production: increasing age, increasing prostate size, ejaculation, urinary infection, prostatitis, prostate injury (such as a biopsy) and prostate cancer. Additionally, there are many men who have an elevated PSA who do not have any of these conditions. Although PSA is not completely specific or sensitive for detecting prostate disease, including cancer, it remains an extremely useful indicator of the risk of prostate disease and the need for further investigation. For further information on PSA see
Prostate Cancer.
IPSS (International Prostate Symptom Score)
The IPSS is a questionnaire designed to determine the seriousness of a man's urinary symptoms and to help diagnose BPH. The patient answers seven questions related to common symptoms of BPH. How frequently the patient experiences each symptom is rated on a scale of 1 to 5. These numbers added together provide a score that is used to evaluate the condition. An IPSS score of 0-7 means the condition is mild; 8-19, moderate; and 20-35, severe.
The IPSS questionnaire
Flow rate (FR) is a simple test performed to determine how quickly a bladder can be emptied and is used to quantify the presence or absence of obstruction, which may indicate BPH. With a comfortably-full bladder, the patient urinates into a machine which measures the rate of urine flow. A ‘bell’-shaped curve with a maximum flow of 15 ml/sec is normal.
Post-void residual (PVR) test measures the amount of urine that remains in the bladder by means of an ultrasound scan, usually after a flow rate. Up to 100 ml is normal.
Cystoscopy or telescopic inspection of the bladder is usually performed in patients with ‘irritative’ bladder symptoms to exclude physical bladder irritants, such as a stone or cancer, which are unusual. It can be performed awake under local anaesthetic and using a flexible telescope or whilst asleep under general anaesthetic.
Urodynamic testing involves filling the bladder via a catheter (tube) inserted through the penis and measuring its behaviour (via a second catheter in the penis and a third in the rectum) as it fills and empties. It can be an uncomfortable and undignified test and fortunately is not often necessary as other methods exist to obtain the same information in most patients. However, then these tests are equivocal, urodynamics often provide the answer.
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