Benign Prostatic Hyperplasia

Aka: Benign Prostatic Hyperplasia, Benign Prostatic Hypertrophy, Prostatic Hyperplasia, BPH

1. Epidemiology
   1. Incidence of BPH increases with age
      1. Men aged 60 years: 50%
      2. Men aged 80 years: 88%
   2. Incidence of symptomatic onset is related to ethnicity
      1. African american men: onset at age 60 years
      2. Caucasian men: onset at age 65 years
2. Pathophysiology
   1. Prostate size increases with age
      1. Birth: few grams
      2. Age 20 to 55 years: 20-30 ml volume (normal)
      3. Age over 55 years: Increased growth (>40 ml volume is considered large)
   2. Prostatic Hyperplasia begins centrally (periurethral)
      1. Prostatic Hyperplasia compresses Urethra
      2. Results in urinary flow obstruction
   3. Prostate growth is hormonally regulated
      1. Testosterone converted to Dihydrotestosterone
      2. Dihydrotestosterone stimulates Prostate growth
      3. Estrogen also stimulates Prostate growth
3. Provocative factors (for Urinary Retention)
   1. See Medication Causes of Urinary Retention
   2. Urinary Tract Infection
   3. Overhydration
   4. Caffeine and other Diuretics
   5. Comorbid conditions
      1. Diabetes Mellitus
      2. Multiple Sclerosis
      3. Parkinson's Disease
   6. Post-operative pelvic floor muscle spasm
      1. Herniorrhaphy
      2. Hydrocelectomy
      3. Perirectal Abscess
      4. Rectal trauma or perineal trauma
   7. Natural Products
      1. Ephedra or Ma Huang
      2. Country Mallow
      3. Heartleaf
      4. Bitter Orange
4. Symptoms
   1. See International Prostate Symptom Score
   2. Obstructive uropathy symptoms
      1. Weak urine stream with decreased caliber
      2. Hesitancy starting urine stream
      3. Incomplete voiding sensation
      4. Urinary Retention
         1. Double voiding (returning to urinate shortly after)
         2. Straining to empty Bladder
      5. Postvoid or terminal dribbling
   3. Irritative symptoms
      1. Dysuria
      2. Urinary frequency
      3. Urinary urgency
   4. Increased urine Residual Volume symptoms
      1. Nocturia
      2. Overflow Incontinence
      3. Bladder palpable on exam
5. Signs
   1. Digital Rectal Exam
      1. Findings suggestive of Prostate Cancer
         1. Asymmetry
         2. Induration
         3. Nodularity
         4. Diffuse firmness
      2. Findings suggestive of Benign Prostatic Hyperplasia
         1. Symmetric prostatic enlargement
         2. Smooth
         3. Firm but elastic
      3. Findings suggestive of Prostatitis
         1. Prostate tenderness
         2. Fever
   2. Abdominal and genitourinary exam
      1. Suprapubic swelling of distended Bladder
      2. Signs of Urethral stricture
         1. Penile induration
         2. Penile nodularity
      3. Balanoposthitis - meatal stenosis (Diabetes Mellitus)
6. Differential Diagnosis
   1. See Urinary Retention
   2. Medication Causes of Urinary Retention
7. Labs
   1. Urinalysis (Urine Dipstick with urine microscopy)
      1. Urinary Tract Infection
      2. Hematuria
   2. Prostate Specific Antigen (PSA)
      1. Prostate Cancer
      2. Evaluate Prostate size (determines efficacy for 5a-Reductase Inhibitor)
   3. Urine cytology
      1. Consider if risk of Bladder Cancer
   4. Renal Function Tests (Serum Creatinine and Blood Urea Nitrogen)
      1. Assess for Postrenal Azotemia
      2. No longer recommended since BPH does not affect baseline renal disease risk
8. Diagnostics
   1. See Urodynamics
   2. Transabdominal Ultrasound
      1. Assess post-void residual
   3. Other studies to consider
      1. Transrectal Ultrasound (Prostate size evaluation)
      2. Intravenous pyelogram (assess urinary obstruction)
9. Management: Conservative Measures for mild symptoms
   1. Limit night-time water consumption
   2. Reduce caffeine intake
   3. Avoid provocative medications
      1. See risk factors above
      2. Avoid anticholinergics (e.g. Antihistamines)
   4. Observe for complications with annual examination
   5. Alternative Medications
      1. Saw Palmetto 160 mg orally twice daily
         1. Mixed results from studies regarding efficacy (see Saw Palmetto)
         2. Initial studies suggested benefit, but 2006 Placebo-controlled study did not
            1. Bent (2006) N Engl J Med 354: 557-66
      2. Soy products (Isoflavone Genistein)
         1. Tofu contains high concentrations of Genistein
         2. Trinovin (OTC Genistein derived from red clover)
            1. Reduced BPH symptoms at 40-80 mg qd (small trial)
         3. References
            1. Lowe (2000) Patient Care 34:191-203
10. Management: Medication
    1. Indications
       1. Benign Prostatic Hyperplasia Symptom Index 8 or higher
    2. Protocol: Combination option
       1. Consider for large Prostate and moderate obstructive symptoms
       2. First 2-3 months (allows for delay in 5a-Reductase Inhibitor activity onset)
          1. Alpha Adrenergic Antagonist and
          2. 5a-Reductase Inhibitor
       3. Next
          1. Continue 5a-Reductase Inhibitor
          2. Taper or discontinue Alpha Adrenergic Antagonist
    3. Alpha Adrenergic Antagonists (long-acting)
       1. Preferred over 5a-Reductase Inhibitors (Finasteride)
       2. Non-Selective agents (antihypertensives, less expensive than Flomax)
          1. Terazosin (Hytrin)
          2. Doxazosin (Cardura)
          3. Prazosin (Minipress)
       3. Selective agents (no Blood Pressure effect)
          1. Tamsulosin (Flomax)
    4. 5a-Reductase Inhibitor (Testosterone conversion inhibitor)
       1. Efficacy: See Finasteride
          1. Less effective than alpha blockade or surgery
          2. Most effective in men with large Prostate (>40 ml)
             1. Digital Rectal Exam predicts size
             2. See PSA for estimating Prostate size
          3. Finasteride effective in reducing Gross Hematuria due to BPH (80%)
       2. Agents
          1. Dutasteride (Duagen)
          2. Finasteride (Proscar)
             1. See Finasteride regarding increased high grade Prostate Cancer risk
11. Management: Surgery
    1. Indications
       1. Benign Prostatic Hyperplasia Symptom Index 20 or higher
       2. Failed medical therapy
       3. Refractory Urinary Retention
       4. Recurrent Urinary Tract Infections
       5. Persistant Hematuria
       6. Bladder stones
       7. Renal Insufficiency
    2. Invasive Procedures
       1. Transurethral Resection of the Prostate (TURP)
       2. Open Prostatectomy (rarely used for BPH alone)
          1. Very large Prostate size
          2. Large median Prostate lobe protruding into Bladder
          3. Urethral diverticulum
12. Management: Surgery with minimally invasive procedures
    1. Advantages
       1. Lower complication rates
    2. Disadvantages
       1. Typically no tissue samples for histopathology testing
       2. Some procedures are less effective or have higher failure rates than TURP
    3. Procedures inpatient (with good efficacy compared with TURP)
       1. Transurethral Incision of the Prostate (TUIP)
          1. Indicated for BPH in smaller Prostate size (<30 ml)
       2. Transurethral Laser Induced Prostatectomy (TULIP)
          1. Ultrasound-guided Nd-Yag laser (or Holmium: Yag Laser)
          2. Shorter procedure and fewer complications than TURP
          3. Similar efficacy for large Prostates (>60 grams) as TURP at 2 years
          4. Wilson (2006) Eur Urol 50(3):569-73
    4. Procedures outpatient
       1. Transurethral Microwave Thermotherapy (TUMT)
          1. Microwave probe heats to over 45 C)
          2. Safe, effective method for Urinary Retention relief
       2. Transurethral Vaporization of the Prostate (TUVP)
       3. Transurethral Electrovaporization Prostate (TVP)
       4. Hot Water Ballon Thermoablation
          1. Experimental procedure with good outcomes
          2. Minimal discomfort
    5. Procedures falling out of favor due to low efficacy or higher risk
       1. Transurethral Needle Ablation of Prostate (TUNA)
          1. High failure rate (23% at 5 years, 83% at 10 years)
          2. Rosario (2007) J Urol 177(3): 1047-51
       2. Urethral stent
          1. Risk of infection and re-blockage
          2. Indications
             1. BPH patients with high surgical risk
             2. Short life expectancy
       3. Transurethral Balloon Dilation
          1. Rarely used due to high rate of symptom recurrence
13. Complications
    1. BPH is not related to Prostate Cancer development
    2. Obstructive complications
       1. Postrenal Azotemia
       2. Hydronephrosis
       3. Bladder decompensation
          1. Overflow Incontinence
          2. Bladder hypertrophy
       4. Urosepsis
14. References
    1. Dornbland (1992) Adult Ambulatory Care, p. 249-52
    2. Cooner (1994) Prostate Disease, AAFP, p. 9-15
    3. Corica (2000) Urology 56:76-81
    4. Donovan (2000) J Urol 164:65-70
    5. Dull (2002) Am Fam Physician 66(1):77-84
    6. Edwards (2008) Am Fam Physician 77(10): 1403-10
    7. Guthrie (1997) Postgrad Med 101(5):141-62
    8. Macchia (Feb, 1997) Consultant, p.336-45
    9. Oesterling (1995) N Engl J Med 332(2):99-109