Differential Diagnosis for Erectile Dysfunction, Reduced Ejaculation Volume, and Libido Loss

Given the symptoms of erectile dysfunction, reduced ejaculation volume, and libido loss, with normal bioavailable testosterone levels, the following differential diagnoses are considered:

• Single Most Likely Diagnosis
  • Hypogonadism (despite normal bioavailable testosterone, other aspects of hormone levels or sensitivity could be at play)
    • Justification: Even with normal bioavailable testosterone, issues with testosterone sensitivity, other hormone imbalances (e.g., prolactin, thyroid hormones), or problems with the hypothalamic-pituitary-gonadal axis could lead to these symptoms.
• Other Likely Diagnoses
  • Psychological or psychiatric issues (depression, anxiety, stress)
    • Justification: Mental health issues are common causes of sexual dysfunction, including erectile dysfunction and decreased libido.
  • Medication side effects (antidepressants, antihypertensives, etc.)
    • Justification: Various medications can cause sexual side effects, including decreased libido, erectile dysfunction, and changes in ejaculation.
  • Lifestyle factors (smoking, alcohol use, obesity)
    • Justification: Lifestyle factors can significantly impact sexual health, contributing to erectile dysfunction, reduced libido, and other sexual health issues.
• Do Not Miss Diagnoses
  • Testicular cancer or other testicular issues
    • Justification: Although less common, testicular cancer or other testicular problems could lead to these symptoms and are critical to diagnose early.
  • Pituitary tumors (prolactinoma)
    • Justification: Pituitary tumors, especially prolactinomas, can cause hypogonadism, leading to the described symptoms, and are crucial to identify due to their potential impact on health.
  • Neurological disorders (multiple sclerosis, Parkinson's disease)
    • Justification: Certain neurological conditions can affect sexual function, and while less common, they are important to consider due to their significant health implications.
• Rare Diagnoses
  • Klinefelter syndrome or other genetic disorders
    • Justification: Genetic conditions like Klinefelter syndrome can lead to hypogonadism and sexual dysfunction but are less common and typically identified earlier in life.
  • Inflammatory or infectious diseases affecting the testes or reproductive system
    • Justification: Conditions such as orchitis or epididymitis can cause sexual dysfunction but are less likely to present with the combination of symptoms described without other signs of infection or inflammation.