Approach
A comprehensive history and physical exam can narrow the diagnosis of the underlying condition.[6] Hormonal studies and imaging are typically used for patients with moderate to severe hirsutism.
History
The following features should be elicited from the history as they may indicate the possible causes of hirsutism.
Onset: rapid progression of hair growth may be due to androgen-secreting neoplasm, particularly when associated with virilization (e.g., male-pattern alopecia, deepening voice, clitoromegaly, increased muscle bulk).
Age: development of excessive coarse hair after the fourth decade of life suggests ovarian hyperthecosis and malignancies.
Presence of virilization: indicates high levels of androgens and raises suspicion of androgen-secreting neoplasia.
Family history: presence of hirsutism in other family members suggests a genetic component as well as idiopathic hirsutism.
Use of medications: use of androgenic medications (anabolic or androgenic steroids, danazol, oral contraceptives with androgenic progestins) may be associated with excessive hair growth.
Menstrual cycles: irregularity (particularly oligomenorrhea) may be due to anovulatory cycles in polycystic ovarian syndrome, nonclassic congenital adrenal hyperplasia, or hyperprolactinemia.
Reproductive history: infertility may be associated with polycystic ovarian syndrome, nonclassic congenital adrenal hyperplasia, or hyperprolactinaemia.
Of note, it is important to differentiate true hirsutism from hypertrichosis, a condition of excessive hair growth in nonmale pattern distribution, which is of hereditary origin or occurs following use of certain medications (glucocorticoids, phenytoin, minoxidil, cyclosporine).
Physical exam
A modified version of the Ferriman-Gallwey visual scale is the most commonly used grading system for diagnosis and follow-up of hirsutism.[7] The scale assesses 9 areas of the body and assigns a score from 0 (absence of hair) to 4 (extensive hair growth). In nonaffected women, the score is typically under 8.[8]
Acanthosis nigricans or polycystic ovary syndrome, particularly when associated with a family history of type 2 diabetes mellitus, suggests insulin resistance.
The presence of galactorrhea may be associated with hyperprolactinemia, particularly in nulliparous women.
Signs of virilization indicate moderately to severely increased androgen levels.
Obesity is associated with increased androgen production and clearance rates.[9] A pattern of fat distribution of truncal obesity associated with a dorsicocervical fat pad and other cushingoid features (purple striae, thin skin, bruising, facial plethora) indicates that Cushing syndrome should be considered.
Palpation of an abdominal or pelvic mass in a hirsute woman is suggestive of androgen-secreting neoplasm.
Polycystic ovary syndrome (PCOS) diagnostic criteria
Women with PCOS may present with various symptoms and signs. According to the revised Rotterdam criteria, 2 of the following 3 criteria must be satisfied to confirm the diagnosis:
Oligo/anovulation
Clinical/biochemical signs of hyperandrogenism
Presence of ≥12 follicles in each ovary, measuring 2 mm to 9 mm in diameter and/or increased ovarian volume (>10 mL) on pelvic/transvaginal ultrasound.
The US National Institutes of Health (NIH) criteria for the diagnosis of PCOS include only the presence of oligo/anovulation and clinical/biochemical signs of hyperandrogenism (after exclusion of other causes for hyperandrogenism).[10]
Hormonal studies
Assessment for elevated androgen levels is not recommended in women with normal menstruation and unwanted local hair growth (i.e., in the absence of an abnormal hirsutism score) because of the low likelihood of identifying a medical disorder.[6]
There is no consensus on laboratory and imaging diagnosis in patients with hirsutism. Hormonal evaluation is recommended in patients with hirsutism; normal reference ranges from local laboratories should always be consulted.[11]
Androgens
Testosterone is the most important androgen to be measured. All women with an abnormal hirsutism score are recommended to have a random serum total testosterone measurement to assess for androgen excess.[6]
Endocrine Society guidelines recommend measuring early morning serum total and free testosterone in premenopausal women who have normal total testosterone, but who have moderate to severe sexual hair growth or mild sexual hair growth in the presence of symptoms or signs suggesting a hyperandrogenic endocrine disorder, such as menstrual disturbance.[6]
High (e.g., with the use of oral contraceptive pills) or low (e.g., in insulin resistance or obesity) concentrations of sex hormone binding globulin may affect total testosterone values. Measurement of sex hormone binding globulin enables calculation of the free androgen index, which will be elevated in hyperandrogenemia caused by PCOS.[12] To calculate the free androgen index, the total testosterone concentration is divided by the sex hormone binding globulin concentration and multiplied by 100.
Total testosterone measured by tandem mass spectrometry is increasingly used.[13] This has higher specificity and less interference with other androgens, such as androstenedione and dehydroepiandrosterone sulfate (DHEAS).[14]
Elevated testosterone concentrations are seen in 60% to 80% of women with PCOS. Very high levels of total testosterone concentration may be caused by an ovarian or adrenal tumor.
Elevated total testosterone concentrations >2 times the upper limit of normal, or a history of rapid virilisation, are likely to be associated with tumor-associated hyperandrogenism.[15] In such cases, DHEAS (secreted mainly by adrenals) and androstenedione (secreted mainly by ovaries) should be measured to identify an adrenal or ovarian source of the hyperandrogenemia.[16]
Measurement of total testosterone, using immunoassays, has a low sensitivity for diagnosing polycystic ovary syndrome (PCOS).[17]
Cortisol
In the presence of cushingoid features, 24-hour urinary free or salivary cortisol should be requested to confirm or rule out Cushing syndrome.
Screening for nonclassic congenital adrenal hyperplasia
Women with elevated androgen levels should be screened for nonclassical congenital adrenal hyperplasia (NCCAH) due to 21-hydroxylase deficiency. This is done by measuring early morning 17-hydroxyprogesterone levels in the follicular phase. For women with amenorrhea/infrequent menses it can be done on a random day.
In women with hirsutism who are considered to have a high risk of NCCAH (e.g., due to positive family history, member of a high-risk ethnic group), screening is recommended even if serum total and free testosterone are normal.[6]
17-hydroxyprogesterone levels >200 nanograms/dL are suggestive of NCCAH and warrant further examination with the adrenocorticotropic hormone (ACTH) stimulation test with 0.25 mg of cosyntropin (synthetic ACTH) followed by measurement of 17-hydroxyprogesterone after 30 and 60 minutes. The diagnosis of NCCAH is confirmed when levels are >1500 nanograms/dL.[18]
An intramuscular depot formulation of cosyntropin is used in cases of suspected adrenocortical insufficiency where the original tests yield inconclusive results.
Prolactin
The presence of galactorrhea and irregular menses warrant determination of serum prolactin levels.
Imaging
The following imaging studies may be warranted:
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