The enlargement of the prostate increasingly narrows the urethra (benign prostatic obstruction (BPO; bladder outlet obstruction, BOO), which leads to disturbances during urination. The bladder has to work against the resistance (= increase in bladder outlet resistance) and the muscles thicken. If the constriction persists for a long time, the bladder can no longer empty completely. Residual urine remains, the amount of which increases more and more, leading to an enlargement of the bladder. However, there is little correlation between the size of the prostate, the degree of obstruction and the severity of symptoms. Patients with small glandular volumes can suffer from both obstructive and irritative symptoms to highly variable degrees. Conversely, patients with very large glandular volumes may be without any impairment of their bladder emptying. If benign prostatic hypertrophy (BPH) is also the cause of micturition symptoms (see above), called lower urinary tract symptoms (LUTS), it is referred to as benign prostatic syndrome (BPS).
Early symptoms
- Pollakiuria – urge to urinate frequently without increased urination.
- Imperative urination (urge to urinate that cannot be suppressed or controlled) with/without urge incontinence (involuntary loss of urine under urge to urinate).
Late symptoms – only after years
- Gradual weakening of the urinary stream
- Delayed onset of bladder emptying
- Micturition is prolonged (prolonged urination) and there is post-micturition dribbling
- Press micturition (pressing to empty the bladder).
- Nocturia – urination at night
- Stranguria – unsuppressible urge to urinate with pain.
- Hematuria – blood in the urine
- Hemospermia – blood in the ejaculate
- Residual urine formation
- Acute ischuria (urinary retention) – emergency situation.
Occasionally, the condition goes almost unnoticed at first and then progresses to chronic ischuria with overflow incontinence.
Further notes
- A low urinary flow rate ((Q) [ml/s]) in otherwise low-symptomatic or symptom-free men places them at increased risk of developing bladder problems in terms of lower urinary tract symptoms (LUTS): A urinary flow rate < 10 ml/s turns out to be predictive.