Why does peripheral tissue hypothyroidism persist despite normal TSH levels and thyroid hormone production following an autoimmune attack on deiodinase enzymes?

💡 Explanation

Peripheral tissue hypothyroidism persists despite normal TSH because local T3 production, essential for cellular function, is impaired by the damaged deiodinase enzymes. This creates a local deficiency. Therefore, option D is correct; rather than the other options, which assume the problem is at the receptor or feedback level when it's a local hormone conversion issue.

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