An individual presents with elevated TSH despite normal T4 levels; the pituitary gland shows no signs of tumors. Which mechanism explains why TSH remains elevated?

💡 Explanation

TSH remains high despite normal T4 levels because of impaired thyroid hormone receptor sensitivity; the pituitary continues to secrete TSH due to lack of negative feedback. Therefore, the thyroid isn't suppressed, rather than T4 levels being low or other thyroid-related factors directly altering TSH secretion.

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