What is the diagnostic approach for Benign Prostatic Hyperplasia (BPH)?

Diagnostic Approach for Benign Prostatic Hyperplasia

The diagnosis of BPH requires a medical history, physical examination including digital rectal exam, urinalysis, and the AUA Symptom Index (IPSS), with serum PSA measurement offered to men with at least 10 years life expectancy. 1, 2

Mandatory Initial Evaluation

The following tests are required for all men presenting with suspected BPH:

Medical History

• Document onset, duration, and severity of lower urinary tract symptoms (LUTS) including both obstructive symptoms (incomplete emptying, weak stream, straining, intermittency) and irritative symptoms (frequency, urgency, nocturia) 1, 3
• Review all medications to exclude drug-induced voiding dysfunction as an alternative cause 1, 3
• Assess for risk factors including family history of prostate disease and fitness for potential surgical procedures 1
• Consider voiding diaries in patients where nocturia is the predominant symptom to document frequency and volume patterns 1

Physical Examination

• Digital rectal examination (DRE) is mandatory to assess prostate size and consistency, and to exclude locally advanced prostate cancer 1, 4
• Perform focused neurologic examination assessing mental status, ambulatory status, lower extremity neuromuscular function, and anal sphincter tone 1
• Assess for bladder distention by palpation or percussion 1, 3

Note that DRE tends to underestimate true prostate size, but if the prostate feels large on DRE, it is usually confirmed enlarged by ultrasound 1

Urinalysis

• Dipstick testing or microscopic examination of urine sediment is mandatory to screen for hematuria and urinary tract infection 1, 3
• This helps exclude bladder cancer, carcinoma in situ, UTIs, urethral strictures, and bladder stones as alternative causes of LUTS 1

Symptom Quantification

• Administer the AUA Symptom Index (identical to the seven symptom questions of the IPSS) at the initial visit 1, 2
• Include the Disease Specific Quality of Life question to measure how bothered the patient is by symptoms 2
• The IPSS is superior to unstructured interviews for quantifying symptom frequency and severity 2
• Readminister IPSS at each follow-up visit to objectively assess symptom changes 2, 5

Serum PSA Measurement

PSA should be offered to two specific patient groups: 1

• Men with at least 10 years life expectancy for whom knowledge of prostate cancer would change management 1, 5
• Men for whom PSA measurement may change the management of their voiding symptoms (as PSA predicts prostate growth, symptom deterioration, acute urinary retention risk, and response to 5-alpha reductase inhibitors) 1

Optional Diagnostic Tests

These tests are not required for initial evaluation but may be appropriate in specific circumstances:

Uroflowmetry and Post-Void Residual (PVR)

• Not necessary prior to watchful waiting or medical therapy 1
• Consider in patients with complex medical history (neurologic disease, prior BPH therapy failure) or those desiring invasive therapy 1
• Men with maximum flow rate (Qmax) <10 ml/sec are more likely to have urodynamic obstruction and benefit from surgery 1
• Large PVR volumes (e.g., 350 ml) may indicate bladder dysfunction but are not contraindications to conservative management 1
• No specific PVR "cut-point" exists for decision-making due to test-retest variability 1

Advanced Testing for Invasive Therapy Candidates

The following are optional when invasive therapies are being considered: 1

• Pressure-flow urodynamic studies: Only test that directly measures bladder and outlet contributions to voiding dysfunction 1

  • Not indicated to predict medical therapy response 1
  • Consider in men with Qmax >10 ml/sec when surgery is planned (higher flow rates suggest less obstruction) 1
  • Useful in patients with prior failed invasive therapy or concomitant neurologic disease 1

• Urethrocystoscopy: Appropriate in men with history of hematuria, urethral stricture, bladder cancer, or prior lower urinary tract surgery 1

  • Not routinely necessary prior to watchful waiting or medical therapy 1
  • Prostate anatomy visualization may guide choice of invasive therapy 1

• Transrectal or transabdominal ultrasound: May be appropriate when minimally invasive or surgical interventions are chosen 1

  • Not routinely necessary prior to watchful waiting or medical therapy 1
  • Prostate size and shape are important for selecting transurethral microwave therapy, TUNA, TUIP versus TURP 1
  • PSA can serve as a proxy for prostate volume in predicting natural history and 5-alpha reductase inhibitor response 1

Urine Cytology

• Optional in men with predominantly irritative symptoms to evaluate for bladder pathology 1

Tests NOT Recommended

• Filling cystometrography (CMG) is not recommended for typical BPH patients 1
• Upper urinary tract imaging (ultrasound or excretory urography) is not recommended unless hematuria is present 1

Common Pitfalls to Avoid

• Do not rely solely on IPSS score without assessing bother level - a moderately symptomatic but highly bothered patient may need intervention more than a severely symptomatic but unbothered patient 2, 6
• Do not use cystoscopy or urodynamics in initial evaluation unless specific risk factors are present 1
• Do not assume all LUTS in older men is BPH - exclude neurologic disease, medications, polyuria, and prior lower urinary tract disease 1
• Do not fail to explain IPSS questions to patients who may not understand the questionnaire intent 2
• Do not use IPSS as a replacement for personal discussion of symptoms with the patient 2