Epidemiology


Etiology

  • Dihydrotestosterone (DHT) is a potent prostatic growth factor.
  • Androgen-estrogen imbalance: As men age, testosterone levels decline, but estrogen levels remain the same, which results in a higher estrogen/testosterone ratio.

Pathophysiology


Clinical features


Diagnostics

Serum PSA level

  • Findings
    • Total PSA > 1.5 ng/mL: suggests an enlarged prostate (> 40 mL)
    • Total PSA > 4 ng/mL: increased likelihood of prostate cancer
  • Free PSA levels and free PSA/total PSA ratio
    • ↑ Free PSA levels and ↑ free PSA/total PSA ratio: usually seen in BPH
    • ↓ Free PSA levels and ↓ free PSA/total PSA ratio: suggestive of prostate cancer

Treatment

Pharmacological therapy

Uroselective alpha-1 blockers

  • Tamsulosin, Doxazosin, Alfuzosin, Terazosin

5-alpha reductase inhibitors (5-ARIs)

  • See Androgen and estrogen synthesis > Adrenal androgen synthesis
  • Inhibition of 5-alpha reductase → ↓ conversion of testosterone to DHT → ↓ intraprostatic DHT levels → ↓ prostatic growth and ↑ prostatic apoptosis and involution → improvement of LUTSPasted image 20230925162608.png
  • Adverse effects: sexual dysfunction (e.g., erectile dysfunction, decreased libido, ejaculatory dysfunction), gynecomastia
  • Finasteride, Dutasteride

Tip

-steride (“testosterone reductase inhibitor”)

Phosphodiesterase type 5 inhibitors (PDE-5 inhibitors)

  • Increase in intracellular cGMP → ↓ detrusor, prostate, and urethra muscle tone → improvement of LUTS
  • Tadalafil

Complications

  • Recurrent UTI
    • BPH → incomplete voiding → urinary stasis → predisposition to UTIs
  • Urinary retention with bladder distension and bladder wall thickening (hypertrophy)
  • Bladder calculi
  • Hydronephrosis
  • Chronic kidney disease