Hypogonadism means the testes or ovaries make too little sex hormone, sperm or eggs. It is primary when the gonads themselves fail and secondary when the pituitary or hypothalamus does not send enough signal through LH and FSH.
Key symptoms
- Low libido and erectile dysfunction in men
- Missed or absent periods and hot flashes in women
- Fatigue, low mood and poor concentration
- Less body hair and loss of muscle
- Infertility; delayed puberty in teens
What you find on exam
- Testicular size and consistency; breast tissue in men
- Body hair pattern and muscle mass
- BMI and waist; obesity can lower testosterone
- Visual fields and sense of smell (Kallmann syndrome)
- Long arms and legs in Klinefelter syndrome
Tests
- Morning total testosterone on two separate days in men
- LH and FSH: high means primary, low or normal means secondary
- Prolactin, iron studies and other pituitary tests; pituitary MRI if secondary
- Karyotype if Klinefelter is suspected; estradiol and pregnancy test in women; bone density
Treatment basics
- Treat reversible causes: weight loss, stopping opioids or anabolic steroids, managing sleep apnea
- Testosterone gel or injections for men not seeking fertility
- Estrogen, plus a progestin if the uterus is present, in women
- Gonadotropins (hCG) for men who want fertility
- On testosterone, monitor hematocrit, PSA and bone health
Red flags
- Headache with visual field loss (possible pituitary tumor)
- Very low testosterone with high prolactin
- Hematocrit over 54 percent on testosterone
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.