Section 21. Men's Health Issues

Chapter 239. Prostate Disorders

Topics: Introduction | Benign Prostatic Hyperplasia | Prostate Cancer | Prostatitis

Benign Prostatic Hyperplasia

Benign prostatic hyperplasia is a noncancerous (benign) enlargement of the prostate gland that can make urination difficult.

Benign prostatic hyperplasia (BPH) becomes increasingly common as men age, especially after age 50. The precise cause is not known but probably involves changes induced by hormones, especially testosterone.

As the prostate enlarges, it gradually compresses the urethra and blocks the flow of urine (urinary obstruction). When a man with BPH urinates, the bladder may not empty completely. Consequently, urine stagnates in the bladder, making the man susceptible to kidney stones and urinary tract infections. Prolonged obstruction can damage the kidneys.

Drugs such as over-the-counter antihistamines and nasal decongestants can increase resistance to the flow of urine or reduce the bladder's ability to contract, causing temporary urinary retention in a man with BPH.

Symptoms

BPH first causes symptoms when the enlarged prostate begins to block the flow of urine. At first, a man may have difficulty starting urination. Urination may also feel incomplete. Because the bladder does not empty completely, he has to urinate more frequently, often at night (nocturia). Also, the need to urinate becomes more urgent. The volume and force of the urinary flow may diminish noticeably, and urine may dribble at the end of urination.

Other problems can develop, but these problems affect only a small number of men with BPH. Obstruction of urine flow with urinary retention may increase the pressure in the bladder and slow the flow of urine from the kidneys, putting increased stress on the kidneys. This increased pressure may impede kidney function, although the effect is usually temporary if the obstruction is relieved early. If obstruction is prolonged, the bladder may overstretch, causing overflow incontinence. (see Section 11, Chapter 147) As the bladder stretches, small veins in the bladder and urethra also stretch. These veins sometimes burst when the man strains to urinate, causing blood to enter the urine. Urinary retention can develop, making urination impossible and leading to a full feeling and severe pain in the lower abdomen.

Diagnosis

By feeling the prostate during a rectal examination, a doctor can usually determine if it is enlarged. The doctor inserts his gloved and lubricated finger into the man's rectum. The prostate can be felt just in front of the rectum. A prostate affected by BPH feels enlarged and smooth but is not painful to the touch.

A doctor may take a blood sample, which can be used to assess kidney function. A test to measure the level of prostate-specific antigen in the blood (PSA test) may also be performed in men with BPH in whom prostate cancer is suspected. A urine sample can be examined to make sure there is no infection.

Further tests are not usually needed. However, if the diagnosis is unclear or the severity of BPH is not known, other tests can be useful. An ultrasound scan can measure the size of the prostate or the amount of urine remaining in the bladder after urination. Alternatively, to check for urinary retention, a doctor can insert a catheter through the urethra after the man has tried to empty his bladder.

Treatment

Treatment is not necessary unless BPH causes especially bothersome symptoms or complications (such as urinary tract infections, impaired kidney function, blood in the urine, kidney stones, or urinary retention).

When BPH is treated, drugs are usually tried first. Alpha-adrenergic blockers (such as terazosin, doxazosin, or tamsulosin) relax certain muscles of the prostate and bladder and may ease the flow of urine. Some drugs (such as finasteride) may reverse the effects of the male hormones responsible for the prostate's growth, shrinking the prostate and helping delay the need for surgery or other treatments. However, finasteride may need to be taken for 3 months or more before symptoms are relieved. Also, many men who take finasteride never experience relief of their symptoms.

If drugs are ineffective, surgery can be performed. Surgery offers the greatest relief of symptoms but may cause complications. The most common surgical procedure is transurethral resection of the prostate (TURP), in which a doctor passes an endoscope (a flexible viewing tube) up the urethra. Attached to the endoscope is a surgical instrument that is used to remove part of the prostate. TURP is usually performed using spinal anesthesia. The procedure spares the man from a surgical incision.

TURP requires overnight hospital admission and can lead to such complications as infection and bleeding. Also, about 5% of the men who undergo the procedure have urinary incontinence afterward, which is usually temporary; permanent incontinence develops in about 1% of men. The procedure causes permanent erectile dysfunction (impotence) in about 5 to 10% of men. About 10% of men undergoing TURP need the procedure repeated within 5 years. Various alternative surgical treatments offer less symptom relief than TURP; however, the risk of complications is lower. Most of these procedures are done with instruments inserted through the urethra. These treatments destroy prostate tissue with microwave heat (transurethral thermotherapy or hyperthermia), a needle (transurethral needle ablation), ultrasound (high intensity focused ultrasound), electric vaporization (transurethral electrovaporization), or lasers (laser therapy). Inflating a balloon inserted through the urethra can also forcibly widen the prostate (transurethral balloon dilation).

Problems resulting from urine obstruction may need treatment prior to definitive treatment of BPH. Urinary retention can be treated by draining the bladder with a catheter inserted through the urethra. Infections can be treated with antibiotics.