Question

a 49 - year - old female patient presents to your office with headaches, anxiety, and weight loss. lab results reveal decreased triiodothyronine, increased thyrotropin - releasing hormone, and decreased thyroid stimulating hormone. which of the following is the most likely diagnosis?
a) addisons disease
b) cushings disease
c) hashimotos
d) pituitary adenoma
e) graves disease

Explanation:

Let's analyze each option:

• Addison's Disease: It is related to adrenal gland dysfunction, not thyroid - related hormone imbalances as described.
• Cushing's Disease: It is associated with excess cortisol production (usually due to pituitary adenoma secreting ACTH), not the given thyroid - hormone profile.
• Hashimoto's: In Hashimoto's (hypothyroidism), we expect increased TSH (thyroid - stimulating hormone). But here, TSH is decreased.
• Pituitary Adenoma: A pituitary adenoma can disrupt the normal hormonal feedback loop. If the pituitary gland (which secretes TSH) is affected (e.g., a non - functional adenoma compressing the normal pituitary tissue), we can see decreased TSH (so decreased triiodothyronine as TSH stimulates thyroid hormone production) and increased thyrotropin - releasing hormone (TRH) due to the lack of negative feedback from TSH on the hypothalamus.
• Graves Disease: It is a hyperthyroid condition (increased thyroid hormones, decreased TSH). But here, triiodothyronine is decreased.

Answer:

d) Pituitary Adenoma