Question

Discuss the pathophysiology of congenital hypothyroidism and the therapeutic management

Answer 1

Congenital hypothyroidism is a severe deficiency of thyroid hormone in newborns. The condition may occur because of a problem with the baby’s thyroid gland, or a lack of iodine in the mother’s body during pregnancy. It causes impaired neurological function, stunted growth, and physical deformities.

Congenital hypothyroidism in newborns can be caused by:

1. A missing, poorly formed, or abnormally small thyroid gland

1. A genetic defect that affects thyroid hormone production
2. Very little iodine in the mother’s diet during pregnancy
3. Radioactive iodine or antithyroid treatment for thyroid cancer during pregnancy
4. Use of medicines that disrupt thyroid hormone production — such as antithyroid drugs, sulfonamides, or lithium — during pregnancy

Mutations in GLIS3 are responsible for congenital hypothyroidism. GLIS3 is highly expressed in the thyroid, and congenital hypothyroidism in patients with GLIS3 mutations may be associated with either thyroid dysgenesis or a eutopic but histologically abnormal thyroid gland. Another genetic variants in CDCA8 (also called BOREALIN) were identified in a study. This gene is expressed in the thyroid and is known to play a key role in the chromosomal passenger complex. However, this mechanism is still unclear.

The main treatment is to give the baby thyroid hormone (levothyroxine). This condition must be treated within the first 4 weeks after birth or the mental disability may be permanent.

Thyroid hormone comes in a pill that parents can crush up into their baby’s breast milk, formula, or water. Parents need to be cautious about using some formulas. Soy protein and concentrated iron formulas can interfere with the absorption of thyroid hormone. Once babies are on thyroid hormone medication, they will have to undergo regular blood thyroid monitoring.

Moreover, this condition can be prevented by supplementing salt with iodine or with other foods as per the eating habits of that region. This is the best method for preventing congenital hypothyroidism.