A 50-year-old woman who is known case of hypothyroidism and is taking treatment for the same, was diagnosed with endometrial fibroids and staed on iron recently. She repoed excessive fatigue & constipation in her follow up visit. Her BP & cholesterol levels have been stable. A TSH is checked, and it is found to be elevated. What is the most likely cause of her elevated TSH?
Ferrous sulfate interferes with absorption of levothyroxine thus leading to low levels of thyroid hormone & elevated levels of TSH In patients with normal body weight taking >200 mg of levothyroxine per day, an elevated TSH strongly suggests noncompliance Malabsorption syndrome (celiac disease)- leads to elevated TSH & increased requirement of thyroxine
Celiac disease
Colon cancer
Medication noncompliance
Poor absorption of levothyroxine due to ferrous sulfate
Diseases of Thyroid