Male hypogonadism

What it is

Hypogonadism means the testes do not make enough testosterone, sperm or both. Primary hypogonadism starts in the testes; secondary hypogonadism starts in the pituitary or hypothalamus and is commonly linked to obesity, opioids, high prolactin or serious illness.

Symptoms

• Low libido and fewer morning erections

• Erectile dysfunction

• Fatigue and low mood

• Loss of muscle and strength

• Anemia and low bone density

How it's diagnosed

The Endocrine Society requires consistent symptoms plus unequivocally low testosterone on at least two early-morning fasting samples. Free testosterone helps when SHBG is abnormal. LH and FSH separate primary from secondary causes, which then guides tests such as prolactin, iron studies and pituitary imaging.

Treatment

Treat what's reversible first: weight, sleep apnea, opioids and other medicines. Confirmed deficiency is treated with testosterone gel, injection, oral or nasal forms. Testosterone suppresses sperm production, so men trying to conceive need a different approach. In the TRAVERSE trial, testosterone was noninferior to placebo for major cardiovascular events in men with hypogonadism and elevated cardiovascular risk, with more atrial fibrillation, acute kidney injury and pulmonary embolism.

Clinical pearls

• Check hematocrit and PSA before and during treatment.

• A low result in the afternoon or during illness should be repeated.