Diagnosis:

A doctor makes a diagnosis of BPH based on description of symptoms, medical history, physical examination, and various blood and urine tests. The doctor may recommend that the patient sees a urologist for complex test procedures.

Some diagnostic tests are used to rule out cancers of the prostate or bladder as the cause of symptoms. In some cases, symptoms of prostate cancer can be similar to those of BPH. Tests may also be performed to see if BPH has caused any kidney damage.

Medical History

The doctor will ask about the patientâ ' s personal and family medical history, including past and present medical conditions. The doctor will also ask about any medications the patient may be taking that could cause urinary problems

Physical Examination

Digital Rectal Exam. The digital rectal exam is used to detect an enlarged prostate. The doctor inserts a gloved and lubricated finger into the patient's rectum and feels the prostate to estimate its size and to detect nodules or tenderness. The exam is quick and painless. The test helps rule out prostate cancer or problems with the muscles in the rectum that might be causing symptoms, but it can underestimate the prostate's size. It is never the sole diagnostic tool for either BPH or prostate cancer.

Other Physical Examinations. The doctor will usually press on and manipulate (palpate) the abdomen and sides to detect signs of kidney or bladder abnormalities. The doctor will also check for signs of swelling in the legs and arms. Certain procedures that test reflexes, sensations, and motor response may be performed in the lower extremities to rule out possible neurologic causes of bladder dysfunction.

Prostate Specific Antigen (PSA) Test

A PSA test measures the level of prostate-specific antigen (PSA) in the patient's blood. It is a widely used but controversial screening test for prostate cancer. High PSA levels may indicate prostate cancer, but BPH itself usually raises PSA levels. [For more information, see In-Depth Report #33: Prostate cancer .]

Urinalysis

A urinalysis can detect signs of bleeding or infection. A urinalysis involves a physical and chemical examination of a urine sample. A urinalysis also helps rule out bladder cancer.

Uroflowmetry

To determine whether the bladder is obstructed, an electronic test called uroflowmetry measures the speed of urine flow. To perform this test, the patient urinates into a special toilet equipped with a measuring device. A reduced flow may indicate BPH. However, bladder obstruction can also be caused by other conditions including weak bladder muscles and problems in the urethra.

Cystoscopy

Cystoscopy, also called urethrocystoscopy, is a test performed by a urologist to check for problems in the lower urinary tract, including the urethra and bladder. The doctor can determine the presence of structural problems including enlargement of the prostate, obstruction of the urethra or neck of the bladder, anatomical abnormalities, or bladder stones. The test may also identify bladder cancer, and causes of blood in the urine and infection.

In this procedure, a thin tube with a light at the end (cytoscope) is inserted into the bladder through the urethra. The doctor may insert tiny instruments through the cytoscope to take small tissue samples (biopsies). Cytoscopy is typically performed as an outpatient procedure. The patient may be given local, spinal, or general anesthesia.

Ultrasound

Ultrasound is a painless procedure that can give an accurate picture of the size and shape of the prostate gland. Ultrasound may also be used for detecting kidney damage, tumors, and bladder stones. Ultrasound tests of the prostate generally use one of two methods:

• Transrectal ultrasonography (TRUS) uses a rectal probe for assessing the prostate. TRUS is significantly more accurate for determining prostate volume.
• Transabdominal ultrasonography uses a device placed over the abdomen. It can give an accurate measure of postvoid residual urine and can be used to check for kidney damage caused by severe BPH.

Postvoid Residual Urine

The postvoid residual urine volume (PVR) test measures the amount of urine left after urination. Normally, about 50 mL or less of urine is left; more than 200 mL is a sign of abnormalities. Measurements in between require further tests. The most common method for measuring PVR is with a catheter, a soft tube that is inserted into the urethra within a few minutes of urination. PVR can also be measured using transabdominal or suprapelvic ultrasonography.

Ruling Out Other Causes of Symptoms

In addition to prostate cancer, other conditions and factors can cause lower urinary tract symptoms similar to those associated with BPH:

Structural Abnormalities. Abnormalities in the urinary tract can cause BPH-like symptoms. These abnormalities include narrowing of the urethra, weakened bladder, and prostate muscle contractions. Such conditions can produce obstruction, impairor weaken the detrusor muscles surrounding the bladder, or cause other damage that impacts the urinary tract.

Prostatitis. Prostatitis is an inflammation of the prostate gland that can be caused by bacterial or nonbacterial factors. (The most common form of prostatitis is nonbacterial, a condition also called prostatosis.) Symptoms include urgent need to urinate, frequent urination, and the need to urinate at night. Pain may occur in the lower back or rectum, or it may develop after ejaculation.

Medications. A number of medications can cause lower urinary tract symptoms or urinary retention, and can worsen symptoms of BPH. These medication classes include antihistamines, decongestants, diuretics, opiates, and tricyclic antidepressants.