Iodine's Inhibition of Thyroid Hormone Production
High concentrations of iodine impact thyroid function significantly. Specifically, excessive iodine intake leads to a temporary decrease in thyroid hormone synthesis and release.
- Effect Description: The condition where very high iodine levels inhibit thyroid hormone synthesis and release.
- Mechanism: This occurs due to the inhibition of iodine organification and the coupling of iodotyrosines, processes crucial for hormone production.
- Name: This specific physiological response is known as the Wolff-Chaikoff effect.
While the Jod-Basedow effect describes the opposite (iodine-induced hyperthyroidism in iodine deficiency), the Wolff-Chaikoff effect specifically refers to the inhibitory action of excess iodine.
Therefore, the correct term for the inhibition of thyroid hormone synthesis and release by very high iodine concentrations is the Wolff-Chaikoff effect.
Important Questions from Thyroid Disorders
- Which one of the following diseases is characterized by destructive lymphoid infiltration of the thyroid gland leading to fibrosis and enlargement of the thyroid gland with an increased risk of developing thyroid lymphoma?
With regards to treatment of thyrotoxicosis of Grave's disease, consider the following statements:
1. Propylthiouracil is suitable in breastfeeding patients.
2. Large goitre is an indication for thyroidectomy.
3. Radioiodine is recommended for management in pregnancy.
4. Agranulocytosis is a complication associated with carbimazole.
Which of the statements given above are correct?
With regard to management of hypothyroidism, consider the following statements:
1. Treatment is with levothyroxine replacement.
2. It is taken as a single daily dose.
3. Average dose is 1.6 $\mu$gm/kg/day.
4. Full dose per weight should be started in those with coronary artery disease.
Which of the statements given above are correct?
- Low serum thyroglobulin levels are seen in
- A 27-year lady underwent thyroidectomy for thyroid carcinoma. Post-operatively she started developing muscle cramps, perioral and peripheral paresthesia, and carpopedal spasm. Which one of the following interventions will be appropriate for this patient?
