If a patient with a history of iodine deficiency undergoes gastric bypass surgery, which consequence on thyroid hormone regulation is most likely?

💡 Explanation

Gastric bypass can impair nutrient absorption, including selenium, required for deiodinase enzymes that convert T4 to T3. This leads to reduced peripheral T4 to T3 conversion because less selenium impairs deiodinase activity; therefore, T3 levels decrease, rather than affecting TSH secretion directly.

• Why does calcium oxalate, rather than calcium phosphate, primarily form kidney stones in individuals with hypocitraturia?
• If a genetically predisposed individual encounters a novel environmental antigen, which consequence relating to the immune system is most likely to drive an autoimmune response?
• Why does chronic nerve compression lead to amplified pain signals from nociceptors even after the compression is relieved?
• Which reduced feedback results when skin mechanoreceptors degrade?
• An orally administered drug undergoes significant first-pass metabolism. If the intestinal CYP3A4 enzyme is inhibited, which consequence follows?
• If a patient's liver sinusoidal endothelial cells lose fenestrations following chronic alcohol abuse, which consequence follows?