Differential Diagnosis for PCOS
When considering a diagnosis of Polycystic Ovary Syndrome (PCOS), it's crucial to rule out other conditions that may present with similar symptoms. The differential diagnosis can be organized into the following categories:
Single Most Likely Diagnosis
- PCOS itself is the most likely diagnosis when a patient presents with a combination of oligomenorrhea or amenorrhea, hyperandrogenism (such as acne, hirsutism), and polycystic ovaries on ultrasound. The diagnosis is typically made based on the Rotterdam criteria, which require at least two out of three of these features.
Other Likely Diagnoses
- Thyroid Dysfunction: Both hypothyroidism and hyperthyroidism can cause menstrual irregularities and are common enough to be considered in the differential diagnosis of PCOS.
- Hyperprolactinemia: Elevated prolactin levels can lead to menstrual irregularities, galactorrhea, and sometimes hirsutism, overlapping with PCOS symptoms.
- Congenital Adrenal Hyperplasia (CAH): This genetic disorder can cause hyperandrogenism and menstrual irregularities, similar to PCOS.
- Cushing’s Syndrome: Although rare, Cushing’s Syndrome can present with weight gain, hirsutism, and menstrual irregularities, mimicking PCOS.
Do Not Miss Diagnoses
- Androgen-Secreting Tumors: Although rare, these tumors can cause rapid onset of hyperandrogenic symptoms and must be ruled out due to their potential for malignancy and significant impact on health.
- Pituitary Adenomas: Especially prolactinomas, which can cause significant hormonal imbalances and have a substantial impact on fertility and overall health.
Rare Diagnoses
- Gonadal Dysgenesis: Conditions like Turner syndrome can present with menstrual irregularities but are distinguished by karyotypic abnormalities.
- Acromegaly: Caused by excess growth hormone, often due to a pituitary tumor, which can lead to menstrual irregularities among other symptoms.
- Primary Ovarian Insufficiency: Premature menopause can sometimes be confused with PCOS due to the presence of amenorrhea, but it is distinguished by elevated FSH levels and the absence of hyperandrogenism.