Differential Diagnosis for Amenorrhea
- Single Most Likely Diagnosis
- Premature Ovarian Insufficiency (POI): This is the most likely diagnosis given the patient's elevated FSH levels, which indicate decreased ovarian function. The history of a suction curettage and IUD placement may have contributed to the development of POI, although the exact cause is often multifactorial. The patient's family history of fragile X syndrome, which is associated with an increased risk of POI, further supports this diagnosis.
- Other Likely Diagnoses
- Asherman's Syndrome: This condition, characterized by intrauterine adhesions, can cause amenorrhea and is a possible complication of the patient's previous suction curettage. The patient's history of progressively lighter bleeding after IUD placement and the absence of withdrawal bleeding on the progesterone withdrawal test support this diagnosis.
- Hypothalamic Amenorrhea: Although the patient has not reported any significant weight changes or stressors, her generalized anxiety disorder could potentially contribute to hypothalamic dysfunction, leading to amenorrhea.
- Do Not Miss Diagnoses
- Pituitary Tumor: Although the patient's TSH is normal, a pituitary tumor could still be present and causing amenorrhea. The absence of galactorrhea or vision changes does not rule out this diagnosis, and further evaluation with imaging studies may be necessary.
- Ovarian Tumor: An ovarian tumor could cause elevated FSH levels and amenorrhea. Although the pelvic examination did not reveal any adnexal masses, a tumor could still be present and should be investigated with imaging studies.
- Rare Diagnoses
- Fragile X-Associated Primary Ovarian Insufficiency: Given the patient's family history of fragile X syndrome, this rare condition is a possible diagnosis. However, it is less likely than POI, and further genetic testing would be necessary to confirm the diagnosis.
- Autoimmune Oophoritis: This rare condition, characterized by autoimmune destruction of the ovaries, could cause POI and amenorrhea. However, it is a less common diagnosis and would require further evaluation with autoimmune antibody testing.