Dermatologic Manifestations of Hirsutism Workup

After familial and drug-induced causes for hirsutism have been excluded, hirsutism resulting from androgen excess should be considered. Initial screening for total or free testosterone and dehydroepiandrosterone sulfate (DHEA-S) often determines whether further testing is necessary. Testosterone and DHEA-S levels may provide clues to the source of excessive androgen production.

Serum testosterone

Whether total testosterone is a better screening test than free testosterone is controversial. The evaluation of total testosterone is less expensive and probably easier to interpret. However, free testosterone may be a more sensitive indicator of hormonal level abnormality.

Early morning testing is advised to measure testosterone levels. The upper limit of the reference range for total plasma testosterone levels varies by laboratory, but it is generally in the range of 70-90 ng/dL. Also note that testosterone levels vary during the different phases of the menstrual cycle by approximately 25%.

No direct correlation exists between the levels of testosterone and the degree of hirsutism, because hirsutism is caused by the action of dihydrotestosterone, which is the more potent testosterone metabolite. Elevated free serum testosterone levels (>80 ng/dL) are found in most women with anovulation and hirsutism. In most patients in whom the total testosterone level is greater than 200 ng/dL (>100 ng/dL in postmenopausal women), a tumor workup is indicated. This workup includes a pelvic examination and ultrasound imaging, which usually are adequate to diagnose polycystic ovarian syndrome (PCOS). If the test results are negative, an adrenal computed tomography scan is performed.

Serum DHEA-S

In some patients who are hirsute, the DHEA-S level is elevated. Moderate elevations suggest an adrenal origin of the hirsutism. Normal levels of DHEA-S accompanied by high levels of testosterone indicate that the ovaries, and not the adrenals, are producing the excess androgen.

A tumor workup is indicated in most patients in whom the DHEA-S level is greater than 700 mcg/dL (400 mcg/dL in postmenopausal women). An increase of this magnitude usually results from adrenal hyperplasia rather than from the extremely rare adrenal carcinomas.

Other laboratory tests

If a woman shows severe or rapidly progressive hirsutism or she shows signs or symptoms of virilism (eg, infrequent or absent menses, acne, deepening of the voice, male-pattern balding, increased muscle mass, increased libido, clitoral hypertrophy), consider performing the following additional tests:

Serum androstenedione

Androstenedione can originate in the adrenal glands or in the ovaries, and the level often is elevated in patients with hyperandrogenism. A serum androstenedione level greater than 100 ng/dL suggests the presence of an ovarian or adrenal neoplasm.

Luteinizing hormone and follicle-stimulating hormone

Often, in women with PCOS, luteinizing hormone (LH) levels are elevated and follicle-stimulating hormone (FSH) levels are depressed, which results in elevated LH/FSH ratios (>2 is common).

17-Hydroxyprogesterone

The screening test for late-onset CAH is a measurement of morning 17-hydroxyprogesterone levels. DHEA-S and 17-ketosteroids levels are normal or moderately elevated. Testosterone and precursors of cortisol levels are elevated. Urinary 17-ketosteroid levels also are elevated slightly in patients with PCOS. A 17-hydroxyprogesterone level greater than 800 ng/dL is diagnostic for 21-hydroxylase deficiency, the most common defect associated with CAH.

An intermediate 17-hydroxyprogesterone level (200-800 ng/dL per distribution of lesions) requires a dexamethasone suppression test, but this level is normal in some women with adult 21-hydroxylase deficiency, and corticotropin stimulation may result in overdiagnosis of the syndrome. Also unclear is whether screening for adult-onset 21-hydroxylase deficiency improves patient outcome, because patients generally do well with empiric antiandrogen therapy, laser hair removal, or both.

If a patient is oligomenorrheic, PCOS is likely. LH, FSH, and prolactin testing suffer from problems with sensitivity and specificity. Testing seldom improves patient outcome.

Urinary cortisol testing

A 24-hour urinary cortisol test should be performed if Cushing syndrome is suspected.

In patients with suspected PCOS or a possible adrenal or ovarian neoplasm, imaging studies of these organs may be required. Consult an endocrinologist or gynecologist for guidance.

Quantification of hirsutism

The definition of hirsutism suggests that the amount of terminal hair needs to be determined before confirming the diagnosis. In 1981, Hatch and coworkers established the current criterion standard for quantification of hirsutism, the modified Ferriman-Gallwey (mFG) score, which is a revised method of the original standard developed by S.M. Garn, D. Ferriman, J.D. Gallwey, and E. Moncada-Lorenzo. ^[6] The mFG score approximates the amount of terminal hair in 9 regions of the female body: upper lip, chin, chest, abdominal region above and below the navel, upper and lower back, arms, and thighs, and then it provides a score from 0 (absent) to 4 (complete coverage) to each of these areas, for a total score ranging from 0 to 36. Hirsutism is characterized as mild within scores up to 15, moderate from 16-25, and severe above 25. ^[6]

The scoring system allows for clinicians and researchers to share a common language in defining the degree of hirsutism. However, a significant limitation of this method lies in the fact that it relies on a subjective nature of assessment.

If a biopsy is performed on a hirsute region, terminal hairs are found; however, a biopsy is not necessary to make the diagnosis.