Diagnosis of Benign Prostatic Hyperplasia (1)

BPH and complications

Benign prostatic hyperplasia (BPH), also called benign prostatic hypertrophy, is a histologic diagnosis characterised by proliferation of prostate cells. Complications related to bladder outlet obstruction (BOO) secondary to BPH include:

• Urinary retention
• Renal insufficiency
• Recurrent urinary tract infections
• Gross haematuria
• Bladder calculi
• Renal failure or uraemia (rare in current practice)

Signs and Symptoms

As the prostate enlarges, it may constrict the flow of urine. Nerves within the prostate and bladder may also play a role in causing the following common symptoms:

• Urinary frequency
• Urinary urgency
• Hesitancy – Difficult, interrupted, weak urinary stream
• Incomplete bladder emptying – feeling of persistent residual urine
• Straining – need strain or push (Valsalva maneuver) to initiate and maintain urination in order to more fully evacuate the bladder
• Decreased force of stream over time
• Dribbling – loss of small amounts of urine due to a poor urinary stream

History

The diagnosis of BPH is often suggested on the basis of the history alone. Symptoms often attributed to BPH can be caused by other disease processes, and a history and physical examination are essential in ruling out other aetiologies of lower urinary tract symptoms (LUTS).

Essential features include:

• Onset and duration of symptoms
• General health issues (including sexual history)
• Fitness for any possible surgical interventions
• Severity of symptoms and how they are affecting quality of life
• Medications
• Previously attempted treatments

Sexual history is important, as epidemiologic studies have identified LUTS as an independent risk factor for erectile dysfunction and ejaculatory dysfunction.

Physical Examination

The digital rectal examination (DRE) is an integral part of BPH evaluation in men. Prostate size and contour can be assessed; nodules and the presence of areas suggestive of malignancy can be detected.

The normal prostate volume in a young man is approximately 20g. Non-urologist examiners may estimate gland size by the number of index finger pads that they can sweep over the rectal surface of the prostate during DRE. Each fingerbreadth correlates to approximately 15-20g of tissue. Most asymptomatic men have glands of 2 fingerbreadths or less.

A more precise volumetric determination can be made using transrectal ultrasonography (TRUS) of the prostate. Generally ultrasonography is not indicated for the initial evaluation of uncomplicated LUTS.

Consider cystoscopy in patients scheduled for invasive treatment or if a foreign body or malignancy is suspected. In addition, endoscopy may be indicated in patients with a history of sexually transmitted disease (eg, gonococcal urethritis), prolonged catheterisation, or trauma.

Laboratory studies

• Urinalysis – to assess the presence of blood, leukocytes, bacteria, protein, or glucose
• Urine culture – to exclude infectious causes of irritative voiding (usually performed if initial urinalysis findings indicate an abnormality)
• Prostate-specific antigen – Although BPH does not cause prostate cancer, men at risk for BPH are also at risk for this disease and should be screened accordingly (note that screening for prostate cancer remains controversial)
• Electrolytes, blood urea nitrogen, and creatinine – to help detect chronic renal insufficiency in patients who have high postvoid residual (PVR) urine volume (although a routine serum creatinine measurement is not indicated in the initial evaluation of men with LUTS secondary to BPH)

IPSS/AUA-SI

The severity of BPH can be determined with the International Prostate Symptom Score (IPSS)/American Urological Association Symptom Index (AUA-SI)*. The International Prostate Symptom Score (I-PSS) is based on the answers to seven questions concerning urinary symptoms and one question concerning quality of life.²

The answers to questions concerning urinary symptoms are assigned points from 0 to 5, indicating increasing severity of the particular symptom. The total score can therefore range from 0 to 35 (asymptomatic to very symptomatic).

1. Incomplete emptying
2. Frequency
3. Intermittency
4. Urgency
5. Weak stream
6. Straining
7. Nocturia

Question eight refers to the patient’s perceived quality of life.

The first seven questions of the I-PSS are identical to the questions appearing on the AUA Symptom Index which categorizes symptoms as follows:

Mild (symptom score less than of equal to 7)

Moderate (symptom score range 8-19)

Severe (symptom score range 20-35)

The SCI strongly recommends that all physicians who counsel patients suffering from lower urinary tract symptoms utilise these measures not only during the initial interview but also during and after treatment in order to monitor treatment response.

*The International Scientific Committee (SCI) has agreed to use the symptom index for BPH developed by the AUA Measurement Committee, as the official worldwide symptoms assessment tool for patients suffering from LUTS.

Other tests

• Flow rate – to help determine the patient’s response to treatment
• PVR urine volume – to gauge the severity of bladder decompensation (can be done invasively with a catheter or noninvasively with a transabdominal ultrasonic scanner)
• Pressure flow studies – to help evaluate for BOO
• Urodynamic studies – to help distinguish poor bladder contraction ability from BOO
• Cytologic examination

Reference:
1- Levi A. Benign Prostatic Hypertrophy. Medscape reference. Available at http://emedicine.medscape.com/article/437359-overview. Updated April 23, 2013.
2- International Prostate Symptom Score (IPSS). Available at: http://www.urospec.com/uro/Forms/ipss.pdf
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