Differentials
Pregnancy
SIGNS / SYMPTOMS
Amenorrhea with breast tenderness, fatigue, nausea, and an enlarging abdomen may be pregnancy.
INVESTIGATIONS
Urine human chorionic gonadotropin (hCG) level >25 IU/L is considered positive for pregnancy.
Urine hCG level <5 IU/L is considered negative for pregnancy.
Polycystic ovary syndrome
SIGNS / SYMPTOMS
Common features include hirsutism, acne, and scalp hair loss; irregular and infrequent periods (often <8 per year); weight gain; and infertility.
Sweating or oily skin may occur.
INVESTIGATIONS
Serum total and free testosterone elevated; serum dehydroepiandrosterone sulfate (DHEAS) elevated.
Symptoms typically begin at the time of puberty.
Hyperthyroidism
SIGNS / SYMPTOMS
Menstrual irregularity, hot flashes,[33] tachycardia, tremor, hair loss, anorexia, and weight loss.
INVESTIGATIONS
Thyroid-stimulating hormone levels may be suppressed (<0.01 IU/L).
Hypothyroidism
SIGNS / SYMPTOMS
Heavy bleeding, infrequent or reduced menstrual bleeding/amenorrhea. Other symptoms are fatigue, hair loss, dry skin, constipation, and weight gain.
INVESTIGATIONS
Thyroid-stimulating hormone levels may be elevated (>10 IU/L).
Anorexia
SIGNS / SYMPTOMS
Patients with onset of anorexia later in life may also have amenorrhea, vaginal dryness, and sleep disturbance but usually will also be underweight and may have electrolyte disturbance, anemia, and bradycardia (or other cardiac arrhythmia). They do not experience hot flashes. It is normally possible to differentiate an eating disorder from premature menopause by taking a careful history of eating habits and measuring follicle-stimulating hormone (FSH).
INVESTIGATIONS
FSH levels will be low to normal (c.f., high in menopause). There may be electrolyte disturbance, anemia, and bradycardia in severe cases of anorexia nervosa.
Ovarian reserve tests (anti-Mullerian hormone, antral follicle count) are likely to be normal.
Adverse effects of medications such as nitrates, niacin, raloxifene, or tamoxifen
SIGNS / SYMPTOMS
Tamoxifen and raloxifene (selective estrogen receptor modifiers) can cause hot flashes.
Niacin, prescribed to raise high-density lipoprotein cholesterol levels, can also cause hot flashes.
The medication history should include herbal and alternative preparations.
INVESTIGATIONS
Consider a trial of withholding the pertinent therapy if possible, to see if the hot flashes are primarily medication-induced.
Consider nonhormonal treatments (e.g., clonidine, venlafaxine, gabapentin).
Carcinoid syndrome
SIGNS / SYMPTOMS
Symptoms of carcinoid syndrome include diarrhea and flashes.
Other clinical features include wheeze, palpitations, telangiectasia, and abdominal pain.
INVESTIGATIONS
CBC, serum chromogranin A/B, and 24-hour urinary 5-hydroxyindoleacetic acid (5-HIAA) may be elevated.
Imaging studies to identify location of primary tumor.
Use of this content is subject to our disclaimer