Benign Prostatic Hyperplasia (BPH) Workup

Updated: Mar 22, 2023
  • Author: Levi A Deters, MD; Chief Editor: Edward David Kim, MD, FACS  more...
  • Print

Approach Considerations

The American Urological Association (AUA) has issued a guideline on the management of benign prostatic hyperplasia (BPH). The guideline includes an algorithm for the diagnosis and basic treatment of lower urinary tract symptoms (LUTS), which is presented below. [1]

Benign prostatic hyperplasia. Basic management of Benign prostatic hyperplasia. Basic management of lower urinary tract symptoms (LUTS) in men.

The Diagnosis Improvement in PrimAry Care Trial (D-IMPACT), a prospective, multicenter study in three European countries, identified simple tests for primary care practitioners to diagnose BPH in men who present with LUTS. D-IMPACT found that a diagnostic algorithm including only the objective variables of age, International Prostate Symptom Score (IPSS) and prostate-specific antigen level (PSA), allows accurate diagnosis of BPH in approximately three-quarters of patients who report LUTS. [7]


Urinalysis and Urine Culture

Examine the urine using dipstick methods and/or via centrifuged sediment evaluation to assess for the presence of blood, leukocytes, bacteria, protein, or glucose.

A urine culture may be useful to exclude infectious causes of irritative voiding. It is usually performed if the 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 prostate cancer and should be screened accordingly. Screening for prostate cancer remains controversial and should done after an informed discussion between the physician and patient.

The current American Cancer Society (ACS) guideline for early detection of prostate cancer stresses the importance of involving men in the decision whether to test for prostate cancer. [8] The ACS notes that PSA testing may reduce the likelihood of dying from prostate cancer but poses serious risks, particularly of treatment of prostate cancer that would not have caused ill effects if left undetected.

The ACS recommends that men receive information about the uncertainties, risks, and potential benefits associated with prostate cancer screening. After this discussion, if the patient wishes to proceed with screening (ie, prostate-specific antigen [PSA] testing and digital rectal examination [DRE] for prostate cancer), the ACS recommends that screening start at the following ages:

  • Age 50 years in men at average risk for prostate cancer who are expected to live at least 10 more years

  • Age 45 years in men at high risk for prostate cancer (African Americans and men with a first-degree relative diagnosed with prostate cancer before age 65)

  • Age 40 years in men at very high risk (those with more than one first-degree relative who had prostate cancer at an early age).

A physician should discuss the risks and benefits of PSA screening with the patient. Notably, men with larger prostates may have slightly higher PSA levels.


Electrolytes, BUN, and Creatinine

These evaluations are useful screening tools for chronic kidney disease in patients who have high post-void residual (PVR) urine volumes. A routine serum creatinine measurement is not indicated in the initial evaluation of men with lower urinary tract symptoms (LUTS) secondary to BPH. [1]



Ultrasonography (abdominal, renal, transrectal) and intravenous urography are useful for helping determine bladder and prostate size and the degree of hydronephrosis (if any) in patients with urinary retention or signs of kidney insufficiency. Generally, they are not indicated for the initial evaluation of uncomplicated LUTS.

A systematic review concluded that patients with suspected large post-void residual volumes should undergo a bladder scan for urine volume to assess for bladder outlet obstruction. Urine volumes measured by bladder scanning correlated highly with urine volumes measured by bladder catheterization. Symptoms alone proved insufficient for diagnosis, although an International Prostate Symptom Score of 20 or greater increased the likelihood of bladder outlet obstruction. [9]

Transrectal ultrasonography (TRUS) of the prostate is recommended in selected patients, to determine the dimensions and volume of the prostate gland. The success of certain minimally invasive treatments may depend on the anatomical characteristics of the gland. In patients with elevated PSA levels, TRUS-guided biopsy may be indicated to assess for prostate cancer.

Imaging of the upper tracts is indicated in patients who present with any of the following:

  • Concomitant hematuria
  • A history of urolithiasis
  • An elevated creatinine level
  • High PVR volume
  • History of upper urinary tract infection

Other imaging studies, such as CT scanning and MRI, have no role in the evaluation and treatment of uncomplicated BPH.


American Urological Association Guidelines

The American Urological Association (AUA) has developed rigorous clinical practice guidelines for BPH. [1] The AUA guidelines were based on the 1994 evidence-based guidelines for the diagnosis and treatment of BPH originally created under the auspices of the United States Department of Health and Human Services Agency for Health Care Policy and Research. [10] The AUA updated its guidelines in 2006 and 2010, and reviewed and confirmed their validity in 2014. [1]

The AUA 2010 guideline update lowered the age of the Index Patient from age 50 years or older to age 45 years or older. Two algorithms were published: the algorithm for diagnosis and basic management of LUTS in the Approach section above, and an algorithm for detailed management of bothersome LUTS that persists after basic management, shown below. [1]

Benign prostatic hyperplasia (BPH) diagnosis and t Benign prostatic hyperplasia (BPH) diagnosis and treatment algorithm.

These panels have established the following categories to classify diagnostic tests and studies. A recommended test is one that should be performed on every patient, whereas an optional test is of proven value in selected patients.

Recommended tests

A medical history should be taken to qualify and quantify voiding dysfunction. Identification of other causes of voiding dysfunction and medical comorbidities are essential to properly assess the condition and to determine conditions that may complicate treatment.

The physical examination consists of a focused physical examination and a neurologic examination. The physical examination includes a DRE to measure prostate size and to assess for abnormalities. The neurological examination is geared toward lower-extremity neurologic and muscular function, as well as anal sphincter tone. Examination of the phallus and foreskin occasionally reveals meatal stenosis, unretractable foreskin, penile ulcers, or foreign bodies such as warts.

PSA testing should be offered to any patient with a 10-year life expectancy in whom the diagnosis of prostate cancer would change management.

The severity of BPH can be determined with the International Prostate Symptom Score (IPSS)/American Urological Association Symptom Index (AUA-SI) plus a disease-specific quality of life (QOL) question. The AUA-SI for BPH is a set of 7 questions that has been adopted worldwide and yields reproducible and quantifiable information regarding symptoms and response to treatment. Questions concern incomplete emptying, frequency, intermittency, urgency, weak stream, straining, and nocturia.

The IPSS uses the same 7 questions as the AUA-SI, with the addition of an eighth question, known as the bother score, which is designed to assess perceived disease-specific QOL. The International Prostate Symptom Score">AUA-SI/IPSS questionnaire is available online. Based on the sum of the score for all 8 questions, patients are classified as 0-7 (mildly symptomatic), 8-19 (moderately symptomatic), or 20-35 (severely symptomatic).

Optional tests

Urine flow rate measurement is useful in the initial assessment and to help determine the response to treatment. It may be performed prior to embarking on any active treatments, including medical treatment.

A maximal flow rate (Qmax) is the single best measurement, but a low Qmax does not help differentiate between obstruction and poor bladder contractility. For more detailed analysis, a pressure-flow study (urodynamic testing) is required. A Qmax value of greater than 15 mL/s is considered by many to be normal. A value of less than 7 mL/s is widely accepted as low.

The results of flow rate measurements are somewhat effort- and volume-dependent. Therefore, the best plan to make a reasonable determination of significance is to obtain at least 2 tracings with at least 150 mL of voided volume each time.

Obtain post-void residual (PVR) urine volume in order to gauge the severity of bladder decompensation. PVR can be determined invasively with a catheter or noninvasively with a transabdominal ultrasonic scanner. A high PVR (ie, 350 mL) may indicate bladder dysfunction and/or bladder outlet obstruction and may predict a poor response to treatment.

Although pressure-flow studies are somewhat invasive, requiring catheterization of the urethra and placement of a transrectal pressure transducer, the findings may prove useful for evaluating for bladder outlet obstruction (BOO).

Urodynamic studies are the only way to help distinguish poor bladder contraction ability (detrusor underactivity) from outlet obstruction. BOO is characterized by high intravesical voiding pressures (>60 cm water) accompanied by low urine flow rates (Qmax < 15 mL/s).

Cytologic examination of the urine may be considered in patients with predominantly irritative voiding symptoms. Risk factors for bladder cancer (smoking, previous bladder cancer) should alert the physician to consider this noninvasive test.

Tests that are not recommended

Routine measurement of serum creatinine is not indicated in the initial evaluation of men with LUTS secondary to BPH.


Endoscopy of the Lower Urinary Tract

Cystoscopy may be indicated in patients scheduled for invasive treatment or in whom 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 catheterization, or trauma. Findings may suggest urethral stricture as the cause of BOO, instead of BPH.

Flexible cystoscopy can be easily performed in several minutes in an office-based setting using topical gel-based intraurethral anesthesia without sedation. The appearance of the gland alone on cystoscopy cannot make the diagnosis of obstruction but can help the clinician decide on treatment modalities if intervention is warranted.


Histologic Findings

BPH is characterized by a varying combination of epithelial and stromal hyperplasia in the prostate. Some cases demonstrate an almost pure smooth-muscle proliferation, although most demonstrate a fibroadenomyomatous pattern of hyperplasia.

In the bladder, obstruction leads to smooth-muscle-cell hypertrophy. Biopsy specimens of trabeculated bladders demonstrate evidence of scarce smooth-muscle fibers with an increase in collagen.