Differential Diagnosis for 39-year-old Female with Abnormal Periods

Single Most Likely Diagnosis

• Perimenopausal Transition: The patient's age, elevated FSH (20.2), and low AMH (0.05) suggest she is likely entering perimenopause, a transition period leading to menopause. The irregular periods and hormonal changes support this diagnosis.

Other Likely Diagnoses

• Uterine Leiomyomas (Fibroids): The presence of multiple myomas, including two large ones (3.3cm and 3.0cm), can cause abnormal periods due to their potential to distort the uterine cavity and affect endometrial function.
• Hypothyroidism: The slightly elevated TSH (5.20) indicates mild hypothyroidism, which can contribute to menstrual irregularities. However, the free T4 (2.0) is within the normal range, suggesting that the hypothyroidism may not be severe enough to be the primary cause of her symptoms.
• Polycystic Ovary Syndrome (PCOS): Although the patient's testosterone levels are not significantly elevated, the presence of simple cysts on the ovary and irregular periods could suggest PCOS, especially if other criteria such as clinical signs of hyperandrogenism or ultrasound findings of polycystic ovaries are present.

Do Not Miss Diagnoses

• Pituitary Tumor: Although the prolactin level (9.7) is within the normal range, any abnormality in prolactin or other pituitary hormones could indicate a pituitary tumor, which is a critical diagnosis not to miss due to its potential impact on fertility, vision, and overall health.
• Thyroid Dysfunction: While the patient's TSH is slightly elevated, indicating mild hypothyroidism, it's crucial to monitor and potentially treat thyroid dysfunction due to its effects on menstrual regularity and overall health.

Rare Diagnoses

• Premature Ovarian Failure (POF): Given the patient's age and significantly elevated FSH, POF could be considered, although it is less common than perimenopausal transition.
• Androgen Excess Disorders: Although the patient's testosterone levels are not markedly elevated, conditions like congenital adrenal hyperplasia or androgen-secreting tumors could be considered, especially if there are clinical signs of hyperandrogenism.
• Other Endocrine Disorders: Rare endocrine disorders affecting the hypothalamic-pituitary-ovarian axis could also lead to abnormal periods and should be considered if initial evaluations do not lead to a clear diagnosis.