Benign prostatic hyperplasia, BPH (mechanism of disease)

This is a flowchart on benign prostatic hyperplasia, covering the etiology, pathophysiology, and manifestations.

ADDITIONAL TAGS:
Hormonal factors:
Irritative symptoms:
Risk factors / SDOH
Cell / tissue damage
Structural factors
Benign prostatic hyperplasia
Medicine / iatrogenic
Infectious / microbial
Biochem / metabolic
Immunology / inflammation
Signs / symptoms
Tests / imaging / labs
Neoplasm / hyperplasia
Genetic / hereditary
Flow physiology
Pathophysiology
Etiology
Manifestations
Slit-like prostatic urethral compression
Glandular and stromal hyperplasia in the transition zone (middle) of the prostate
Formation of smooth, elastic, firm hyperplastic nodule
Bladder outlet obstruction
In contrast, outer peripheral zone → prostate cancer
Involuntary detrusor contractions during bladder filling → detrusor overactivity
Bladder wall weakening
Incomplete voiding
Urinary stasis
Urinary retention
Urinary tract infections
Bladder stones
↑ intracystic pressure while voiding
Detrusor muscle hypertrophy
Bladder trabeculation
Bladder mucosa protrude through the layers of the bladder wall
Pseudodiverticula formation
Urinary frequency
Urgency, urge incontinence
Nocturia
Occasional dysuria
Hesitancy (delayed onset)
Straining to urinate
Prolonged terminal dribbling
Poor and/or intermittent stream (not continuous)
Obstructive symptoms:
Incomplete voiding sensation
Acute urinary retention
Digital rectal examination: symmetrically enlarged, smooth (no nodules), firm, nontender prostate with rubbery or elastic texture
In contrast, if DRE shows:
Nodules, hard consistency → prostate cancer
Tenderness on palpation → prostatitis
Dihydrotestosterone is potent prostatic growth factor (converted from testosterone by 5-α-reductase)
Estrogen (estradiol) stimulates prostatic hyperplasia (formed from aromatization of testosterone in fat, hence ↑ in obesity)
Gene amplification of androgen receptors
Genetic susceptibility:
Growth factor genes
Androgen-regulator genes
Apoptosis genes
Androgen-regulated genes
Stem cells in prostatic stroma:
↓ apoptotic factors
↑ antiapoptotic factors
Longer stem cell lifespan