Differential Diagnosis
- Single most likely diagnosis
- A. Hyperprolactinemia: This is the most likely diagnosis given the very high prolactin levels, which can cause infertility, fatigue, weight gain, and constipation. Hyperprolactinemia can also lead to an increase in TSH levels due to the inhibitory effect of prolactin on the hypothalamic-pituitary-thyroid axis.
- Other Likely diagnoses
- B. Hypothyroidism (1ry): Although the primary issue seems to be hyperprolactinemia, the high TSH level indicates hypothyroidism. However, given that FSH and LH are normal, the primary cause of infertility might not be directly related to hypothyroidism but could be a contributing factor.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Pituitary Tumor: A pituitary tumor, especially a prolactinoma, could cause the very high prolactin levels and secondary hypothyroidism due to compression or interference with the normal function of the pituitary gland. Although not directly listed as an option, it's a critical diagnosis to consider due to its potential impact on health.
- Rare diagnoses
- C. Vitamin D deficiency and hypocalcaemia: While vitamin D deficiency and hypocalcemia can have various symptoms, they are less directly linked to the specific combination of high prolactin, high TSH, and the patient's symptoms of infertility, fatigue, weight gain, and constipation. These conditions might contribute to overall health issues but are less likely to be the primary cause of the patient's presentation.