Question

a 34 - year - old female patient presents with fatigue and weight gain. her lab work reveals increased trh, and increased tsh. which of the following is the most likely diagnosis?
a) hashimotos
b) graves disease
c) pituitary adenoma
d) tertiary hypothyroidism
e) secondary hyperthyroidism

Explanation:

• Hashimoto's: Autoimmune thyroiditis leading to hypothyroidism. Low thyroid hormone (T3/T4) causes feedback increase in TRH (from hypothalamus) and TSH (from pituitary). Symptoms like fatigue and weight - gain are common in hypothyroidism.
• Graves' disease: Causes hyperthyroidism. TSH would be low (due to negative feedback from high thyroid hormones), so this is incorrect.
• Pituitary adenoma (if TSH - secreting): Would cause high TSH, but TRH would be low (negative feedback from high TSH on hypothalamus). So not likely.
• Tertiary hypothyroidism: Caused by hypothalamic problem. TRH would be low (primary defect), so TSH would also be low (as TSH is stimulated by TRH). So incorrect.
• Secondary hyperthyroidism: Caused by pituitary over - secretion of TSH. But patient has hypothyroid symptoms (fatigue, weight gain). Also, in hyperthyroidism, metabolism is increased (opposite of symptoms here).

Answer:

a) Hashimoto's