Erection and ejaculation disorders

Erectile dysfunction is the most common presentation of sexual dysfunction in males and is characterized by an inability to maintain an adequate erection for sexual intercourse that lasts at least 6 months. The causes may be psychological, vascular, neurological, or hormonal. Diagnosis is made based on a detailed medical history and physical exam, relevant blood tests (e.g., testosterone, sexual hormone-binding globulin), and objective measurement of the remaining erectile function (nocturnal penile tumescence testing). Treatment includes counseling and, in cases with an organic cause, potentially mechanical vacuum pump therapy, medical therapy with phosphodiesterase-5 inhibitors, or surgery (penile prosthesis implant).

Premature ejaculation is characterized by an inability to delay ejaculation during penetration and is often accompanied by significant psychological distress. Proposed etiologies include penile hypersensitivity and psychological disorders such as depression and anxiety. The diagnosis is made with a medical history of short ejaculation latency time, inability to delay or control ejaculation, and psychological strain. Treatment consists of SSRIs and local topical anesthetics with sex therapy and other psychotherapy as needed.

See “Male sexual response” in “Male reproductive organs” for physiological erection.

Definition

• Erectile dysfunction (impotentia coeundi): inability to achieve or sustain an erection sufficient in rigidity or duration for sexual intercourse which is present for a minimum of ∼ 6 months ^[1]
• See “Infertility” and “Recurrent pregnancy loss.”

Epidemiology

• Most common sexual disorder in men

Etiology

• Organic (most common)
  • Vascular: hypertension, diabetes mellitus, cardiovascular disease, hyperlipidemia, smoking
  • Neurogenic: stroke, brain or spinal cord injury, dementia, Parkinson disease, multiple sclerosis
  • Endocrine: hypogonadism, hyperprolactinemia, thyroid disorders
  • Medications
    • Antihypertensives; (beta-blockers, thiazide diuretics)
    • Antidepressants (SSRIs)
    • Dopamine antagonists (e.g., antipsychotics): increased prolactin secretion (anterior pituitary) → decreased GnRH secretion (hypothalamus) → decreased LH secretion (anterior pituitary) → decreased testosterone production (Leydig cells) → hypogonadotropic hypogonadism
  • Iatrogenic: surgery or radiotherapy (radical prostatectomy, pelvic radiation)
  • Trauma: pelvic fracture and urethral injury
  • Alcohol abuse
  • Peyronie disease
• Psychogenic: depression, anxiety (performance-related), relationship issues, trauma from prior experiences, stress
• Mixed organic and psychogenic

Diagnosis ^[2]

• Largely a clinical diagnosis
• Detailed patient history and clinical exam

Diagnostic criteria (according to DSM V)
A	≥ 1 of the following occur during ≥ 75% of all sexual encounters: Difficulty developing an erection Difficulty maintaining an erection Reduced rigidity of the erection
B	Lasts for a minimum of ∼ 6 months
C	Causes clinically significant distress in the individual
D	Not due to another mental disorder, severe relationship distress, substance abuse, or an organic disorder

• Further tests to exclude organic disorders ^[3]
  • Endocrinological laboratory analysis: ↓ testosterone, ↑ SHBG, ↑ prolactin, ↓ LH, ↓ FSH, ↑ TSH, ↑ fasting glucose or hemoglobin A1C, abnormal lipid profile
  • Nocturnal penile tumescence measurement (phallography): measurement of spontaneous nightly erections in erectile dysfunction (primarily performed in a sleep laboratory) to differentiate between organic from psychogenic erectile dysfunction.
    • Lack of nocturnal erections suggests an organic etiology (neurogenic or vascular)
    • Normal testing suggests a psychogenic etiology
  • Duplex Doppler ultrasound or arteriography to identify suspected arterial inflow or venous leaks after injection of vasodilatory agent

Treatment

Ii is important to identify the underlying etiology to manage lifestyle risk factors and initiate appropriate therapy.

• Psychotherapy
  • Counseling
  • Sensate focus exercises for performance anxiety
  • Group psychotherapy
• Medical therapy
  • Phosphodiesterase-5 inhibitors are considered the only first-line therapy: tadalafil, sildenafil, vardenafil.
    • Contraindicated in patients taking nitrates due to profound hypotension
    • May cause orthostatic hypotension in those taking alpha-adrenergic antagonists (e.g., for BPH) and should therefore be taken at least 4 hours apart
  • Testosterone replacement if patient's serum testosterone is low (e.g., in hypogonadism)
  • Intracavernous injection therapy or prostaglandin E1 (alprostadil) are second-line therapies if PDE-5 inhibitors are ineffective.
• Mechanical
  • Vacuum pump (hollow cylinder that is placed onto the penis) with penis ring (outflow obstruction of the existing erection) is also considered a second-line therapy if PDE-5 inhibitors are ineffective.
  • Often recommended before intracavernous injections as vacuum devices are noninvasive
• Surgical
  • Implantation of penile prosthesis
  • Generally last resort (can be placed, e.g.g, at time of reconstructive surgery for Peyronie disease when erectile dysfunction is also present)
  • Inflatable implants in the cavernous body most commonly used (vs. semi-rigid)

• Definition: fibroproliferative disorder that affects the tunica albuginea of the penis, causing abnormal curvature of the penis
• Pathogenesis: repeated penile microtrauma during sexual intercourse or athletic activity followed by abnormal wound healing → fibrous plaque formation ^[6]
• Clinical features
  • Penile pain
  • Penile nodules/indurations on the affected side of the penis
  • Erectile dysfunction due to abnormal curvature of the penis
  • May be associated with psychological conditions; (e.g., anxiety, depression) ^[7]
• Differential diagnosis
  • Chordee without hypospadias
  • Penile fracture (penile injury → rupture of corpora cavernosa → penile curvature)
• Treatment
  • First-line: oral pentoxifylline
  • Second-line: intralesional collagenase injections
  • Third-line: surgical repair