Benign Prostatic Hyperplasia

Detailed Overview

BPH affects most aging men, causing static obstruction from prostatic tissue and dynamic obstruction from increased alpha-1 adrenergic tone. Prolonged obstruction induces detrusor hypertrophy, bladder instability, and eventually urinary retention or renal injury.

Epidemiology & Demographics

Prevalence is ~50% by age 60 and >90% by age 85. Symptomatic in 25% of men at age 55.

Etiological Mechanism

Driven by aging and the action of dihydrotestosterone (DHT) on prostatic tissue.

Primary Causes

Testosterone conversion to DHT via 5-alpha-reductase stimulates stromal and epithelial hyperplasia.

• Advanced Age: Primary risk factor, linear increase after age 40.
• Metabolic Syndrome: Obesity and insulin resistance increase prostate volume.

DHT binds androgen receptors, triggering growth factors (FGF, EGF) that promote transition zone proliferation. The hyperplastic tissue compresses the urethra (static BOO). Concurrently, alpha-1 receptors in the prostate stroma increase smooth muscle tone (dynamic BOO).

Characteristic Clinical Presentation

• Hesitancy & Weak Stream: Delay in initiating urination and decreased force/caliber of stream.
• Nocturia: Waking >2 times per night to void.
• Incomplete Emptying: Sensation that the bladder is not empty post-void.

Physical Examination Signs

• Enlarged Prostate on DRE
• Palpable Bladder

• Acute Urinary Retention: Sudden inability to void requiring Foley catheterization.
• Post-renal AKI: Obstructive uropathy causing bilateral hydronephrosis and elevated creatinine.

Diagnostic Criteria & Guidelines

Clinical diagnosis via IPSS >7, DRE findings, uroflowmetry (Qmax < 10 mL/s), and post-void residual (PVR) > 100 mL.

Differential Diagnosis

• Prostate Cancer (hard, nodular DRE)
• Urethral Stricture
• Neurogenic Bladder

Laboratory Tests & Biomarkers

• PSA: Mildly elevated (e.g., 2-10 ng/mL) directly correlated to volume.
• Serum Creatinine: Elevated if post-renal obstruction is present.

Imaging Modalities & Findings

• Transrectal Ultrasound (TRUS):
• Renal US:

• Mild
  Observation only.
• Moderate to Severe
  Medical or surgical intervention required.

Second-Line & Adjunctive Therapy

Tadalafil 5 mg PO daily if concurrent erectile dysfunction. Tolterodine 2 mg BID for overactive bladder symptoms if PVR <150 mL.

Surgical & Procedural Management

Transurethral Resection of the Prostate (TURP) for prostates <80g. Holmium Laser Enucleation (HoLEP) or simple prostatectomy for >80g.

Recommended Lifestyle Changes

• Avoid fluids 2 hours before bed.
• Limit caffeine and alcohol.
• Avoid decongestants (pseudoephedrine) and anticholinergics.

Patient Counseling & Advice

Warn that Finasteride halves PSA values (must double when screening for cancer) and can cause decreased libido/ED. Tamsulosin can cause orthostatic hypotension.

Follow-Up & Monitoring Schedule

Yearly IPSS, DRE, PSA, and PVR check.

Preventive Strategies

Maintain healthy weight, routine physical activity.

Progressive disease; 1-2% risk per year of acute urinary retention if untreated.