Differential Diagnoses in Hyperandrogenism

Primary Differential Diagnoses to Exclude

The American Academy of Family Physicians recommends systematically excluding non-classical congenital adrenal hyperplasia (NCCAH), Cushing's syndrome, androgen-secreting tumors, hyperprolactinemia, thyroid disease, exogenous androgen use, and acromegaly before attributing symptoms solely to PCOS 1
Consider Cushing's syndrome in any woman with recent onset hyperandrogenism accompanied by buffalo hump, moon facies, hypertension, abdominal striae, centripetal fat distribution, easy bruising, or proximal myopathy 1
Screen for Cushing's syndrome with overnight dexamethasone suppression test or 24-hour urinary free cortisol measurement 1
Severe, rapidly progressive hyperandrogenism with virilization demands immediate evaluation for androgen-secreting tumors 1
Pelvic examination may reveal ovarian enlargement, and imaging studies are essential for diagnosing androgen-secreting tumors 1
Prolactin disorders can present with similar menstrual irregularities and must be excluded 1
Measure thyroid-stimulating hormone (TSH) in all women with suspected hyperandrogenism to rule out thyroid disease 1

Obtain detailed medication history including supplements, performance-enhancing substances, and anabolic steroids to identify exogenous androgen exposure 1
Certain medications like valproate can trigger or exacerbate PCOS-like symptoms, according to the American College of Obstetricians and Gynecologists 2
Acromegaly is a rare cause of androgen excess, but should be considered in the differential diagnosis 1
Primary hypothalamic amenorrhea and primary ovarian failure can present with hormonal abnormalities mimicking PCOS 1

Recent, rapid onset of severe hyperandrogenism suggests tumor or Cushing's syndrome rather than PCOS 1
Acanthosis nigricans may be associated with insulinoma or malignancy, particularly gastric adenocarcinoma 1
Obesity, chronic anovulation, and hyperinsulinemia increase endometrial cancer risk 1
Clitoromegaly strongly suggests virilizing tumor 1
Rapid progression of hirsutism, severe acne, or male-pattern baldness warrant aggressive workup 1
Palpable ovarian enlargement on pelvic exam suggests possible tumor 1

Initial screening should include TSH, total testosterone or free/bioavailable testosterone, and 17-hydroxyprogesterone 1
If clinical suspicion for Cushing's, perform overnight dexamethasone suppression test or 24-hour urinary free cortisol 1
If severe hyperandrogenism or virilization, consider imaging studies and tumor markers 2