A 52-year-old man comes to the clinic with concerns about his sexual desire. The patient's libido was previously normal but has progressively diminished over the last 6 months. The patient has also experienced fatigue and malaise without weakness or weight changes. He says, "I just do not feel like myself anymore." The patient is married and has 2 children. He reports a satisfying relationship with his wife, although his recent symptoms have been a source of tension between them. The patient's medical issues include gastroesophageal reflux, irritable bowel syndrome, and chronic low back pain from a workplace injury 2 years ago. He underwent spinal surgery after the incident but has had continuing pain, requiring opioid treatment for the last 2 years. Current medications include omeprazole, long-acting oxycodone, and as-needed acetaminophen and polyethylene glycol. He does not use alcohol, tobacco, or illicit drugs.
Vital signs are within normal limits. BMI is 26 kg/m². Physical examination shows normal muscle bulk and body hair distribution. Auscultation of the heart and lungs is normal. Extremities are warm with palpable pulses. The testicles are small in volume with no tenderness or palpable masses. Neurological examination is normal, and visual fields are full to confrontation. Strength is normal in the extremities.
Morning serum total testosterone level is 180 ng/dL (normal 300-1200 ng/dL) , which is consistent on repeat evaluation. Subsequent laboratory testing shows the following:
Which of the following is the most likely cause of the patient's diminished sexual desire?

Question

A 52-year-old man comes to the clinic with concerns about his sexual desire. The patient's libido was previously normal but has progressively diminished over the last 6 months. The patient has also experienced fatigue and malaise without weakness or weight changes. He says, "I just do not feel like myself anymore." The patient is married and has 2 children. He reports a satisfying relationship with his wife, although his recent symptoms have been a source of tension between them. The patient's medical issues include gastroesophageal reflux, irritable bowel syndrome, and chronic low back pain from a workplace injury 2 years ago. He underwent spinal surgery after the incident but has had continuing pain, requiring opioid treatment for the last 2 years. Current medications include omeprazole, long-acting oxycodone, and as-needed acetaminophen and polyethylene glycol. He does not use alcohol, tobacco, or illicit drugs.
Vital signs are within normal limits. BMI is 26 kg/m². Physical examination shows normal muscle bulk and body hair distribution. Auscultation of the heart and lungs is normal. Extremities are warm with palpable pulses. The testicles are small in volume with no tenderness or palpable masses. Neurological examination is normal, and visual fields are full to confrontation. Strength is normal in the extremities.
Morning serum total testosterone level is 180 ng/dL (normal 300-1200 ng/dL) , which is consistent on repeat evaluation. Subsequent laboratory testing shows the following:

Which of the following is the most likely cause of the patient's diminished sexual desire?

Quizplus · Accepted Answer

This patient has decreased libido and fatigue associated with testicular atrophy. He also has a persistently low serum testosterone with inappropriately low FSH and LH levels, which is consistent with secondary (central) hypogonadism rather than primary gonadal dysfunction (Choice E). In the setting of a chronic pain disorder and long-term opioid use, this is most likely opioid-related hypogonadism. Chronic opioid use leads to decreased gonadotropin-releasing hormone secretion and is a common cause of hypogonadism. The hypothalamic-pituitary-adrenal axis can be affected as well. Opioid-related hypogonadism is common in patients on chronic opioid therapy. Additional manifestations can include depression, hot flashes, night sweats, osteoporosis, and menstrual irregularities (in women). The ideal management of opioid-related hypogonadism is cessation of opioid therapy, although dose reduction and rotating opioid types may sometimes be adequate. If symptoms continue and the patient cannot be withdrawn from opioids, androgen replacement therapy may be needed. (Choice B) A primary mood disorder could explain some of this patient's clinical features, including decreased libido. However, his testicular atrophy and metabolic markers of central hypogonadism are more consistent with opioid-related hypogonadism. (Choice C) Serum testosterone levels and sexual function commonly diminish with age. However, libido is typically intact, and this patient is too young to attribute his symptoms to age. (Choice D) Although this patient's gonadotropin levels are low, his TSH (and free T4) levels are normal and he has no specific manifestations of pituitary dysfunction. The primary effect in opioid-related hypogonadism is in the hypothalamus. Educational objective: Chronic opioid use leads to decreased gonadotropin-releasing hormone secretion, and is a common cause of hypogonadism. Patients can develop decreased libido and other manifestations of hypogonadism. Management options include discontinuation, dose reduction, or rotation of opioid types, or androgen replacement therapy. __________ References: Opioid related endocrinopathy. (http://www.ncbi.nlm.nih.gov/pubmed/26461076)

A 52-Year-Old Man Comes to the Clinic with Concerns About