MKSAP Quiz: 3-month history of irregular menses
A 32-year-old woman is evaluated for increased hair growth on the face and chest and a 3-month history of irregular menses. She has a 5-year history of hypothyroidism. Her only medication is levothyroxine. Terminal hair growth of the upper lip, chin, sides of the face, and middle of the chest is noted. Pelvic examination reveals clitoromegaly. What is the most appropriate next diagnostic test?
A 32-year-old woman is evaluated for increased hair growth on the face and chest and a 3-month history of irregular menses. She has a 5-year history of hypothyroidism. Her only medication is levothyroxine.
On physical examination, temperature is 37.0 °C (98.6 °F), blood pressure is 110/72 mm Hg, and pulse rate is 80/min; BMI is 26. Terminal hair growth of the upper lip, chin, sides of the face, and middle of the chest is noted. No acanthosis nigricans or galactorrhea is detected. Palpation of the abdomen reveals no masses. Pelvic examination reveals clitoromegaly.
Laboratory studies:
Which of the following is the most appropriate next diagnostic test?
A. Adrenal CT
B. Free testosterone measurement
C. Pituitary MRI
D. Transvaginal ultrasonography
MKSAP Answer and Critique
The correct answer is D: Transvaginal ultrasonography. This item is available to MKSAP 16 subscribers as item 62 in the Endocrinology and Metabolism section. More information is available online.
The most appropriate next diagnostic test is transvaginal ultrasonography to examine this patient's ovaries. Her history and physical examination findings are consistent with hyperandrogenism. Her total testosterone level is elevated, and her dehydroepiandrosterone sulfate (DHEAS) level is normal. In healthy women, the ovaries and adrenal glands contribute equally to testosterone production. However, a testosterone level greater than 200 ng/dL (6.9 nmol/L) in a woman with rapid onset of hyperandrogenic symptoms (increased hirsutism in a short period of time and clitoromegaly) suggests an ovarian neoplasm, which is best diagnosed with a transvaginal ultrasound.
Dehydroepiandrosterone is produced primarily in the adrenal glands and is sulfated in the adrenal glands, liver, and small intestine to become DHEAS. Levels greater than 7.0 micrograms/mL (18.9 micromoles/L) strongly suggest an adrenal source of androgens. In this patient, whose DHEAS level is only 2.9 micrograms/mL (7.8 micromoles/L), imaging of the adrenals would be the next step only if the transvaginal ultrasound showed no ovarian neoplasm.
A free testosterone measurement is not needed because this patient's history and physical examination findings do not suggest an abnormality in her sex hormone–binding globulin level that would make the total testosterone measurement suspect.
Because elevated androgen levels in women have either an ovarian or an adrenal source, a pituitary MRI would not be useful in this patient.
Key Point
- In a woman with rapid onset of hyperandrogenic symptoms, especially if her testosterone level is greater than 200 ng/dL (6.9 nmol/L), an ovarian neoplasm is likely and is best diagnosed with a transvaginal ultrasound.