Pathophysiology
Clinical meaning
Benign prostatic hyperplasia (BPH) is a non-cancerous enlargement of the prostate gland that results from hyperplasia (increased cell number) of both the stromal and epithelial components of the prostate. The prostate gland is a walnut-sized organ located just below the bladder and surrounding the prostatic urethra. It produces approximately 20-30% of seminal fluid. Two factors are required for BPH development: aging and the presence of androgens, specifically dihydrotestosterone (DHT). Testosterone is converted to DHT by the enzyme 5-alpha reductase within the prostate. DHT binds to androgen receptors and stimulates prostate cell growth. As men age, the balance between cell proliferation and programmed cell death (apoptosis) shifts toward proliferation, leading to progressive glandular enlargement. The enlarged prostate compresses the urethra and causes bladder outlet obstruction, resulting in lower urinary tract symptoms (LUTS). These symptoms are divided into obstructive (voiding) symptoms and irritative (storage) symptoms. Obstructive symptoms include hesitancy (difficulty initiating urination), weak urinary stream, intermittency (start-stop stream), straining to void, prolonged voiding time, incomplete emptying, and post-void dribbling. Irritative symptoms include urinary frequency (voiding more than 8 times per day), urgency...