Chapter 79: Benign Prostatic Hyperplasia

INTRODUCTION

• Benign prostatic hyperplasia (BPH), a nearly ubiquitous condition, is the most common benign neoplasm of American men.

PATHOPHYSIOLOGY

• Three types of prostate gland tissue: epithelial or glandular, stromal or smooth muscle, and capsule. Both stromal tissue and capsule are embedded with α₁-adrenergic receptors.

• The precise pathophysiologic mechanisms that cause BPH are not clear. Both intraprostatic dihydrotestosterone (DHT) and type II 5α-reductase are thought to be involved.

• BPH commonly results from both static (gradual enlargement of the prostate) and dynamic (agents or situations that increase α-adrenergic tone and constrict the gland’s smooth muscle) factors. Examples of drugs that can exacerbate symptoms include testosterone, α-adrenergic agonists (eg, decongestants), and those with significant anticholinergic effects (eg, antihistamines, phenothiazines, tricyclic antidepressants, antispasmodics, and antiparkinsonian agents).

CLINICAL PRESENTATION

• Patients present with a variety of signs and symptoms categorized as obstructive or irritative. Symptoms vary over time.

• Obstructive signs and symptoms result when dynamic and/or static factors reduce bladder emptying. Patients experience urinary hesitancy, urine dribbles out of the penis, and the bladder feels full even after voiding.

• Irritative signs and symptoms are common and result from long-standing obstruction at the bladder neck. Patients experience urinary frequency, urgency, and nocturia.

• BPH progression may produce complications including chronic kidney disease, gross hematuria, urinary incontinence, recurrent urinary tract infection, bladder diverticula, and bladder stones.

DIAGNOSIS

• Includes careful medical history, physical examination, objective measures of bladder emptying (eg, peak and average urinary flow rate and postvoid residual [PVR] urine volume), and laboratory tests (eg, urinalysis and prostate-specific antigen [PSA]).

• On digital rectal examination, the prostate is usually but not always enlarged (>20 g), soft, smooth, and symmetric.

TREATMENT

• Goals of Treatment: The goals are to control symptoms, prevent progression of complications, and delay need for surgical intervention.

• Management options include watchful waiting, drug therapy, and surgical intervention. The choice depends on severity of signs and symptoms (Table 79–1).

• Watchful waiting is appropriate for patients with mild disease (Fig. 79–1). Patients are reassessed at 6 to 12 month intervals and educated about behavior modification, such as fluid restriction before bedtime, minimizing caffeine and alcohol intake, frequent emptying of the bladder, and avoiding drugs that exacerbate voiding symptoms.