Congenital Hypothyroidism: A Review of Diagnosis, Treatment and Long-term Outcomes
Abstract
Congenital hypothyroidism (CH) is a condition in which a newborn’s thyroid gland does not produce enough of the hormones necessary for normal growth and development. CH is a common and serious condition if not diagnosed and treated early. This review provides an overview of CH, including the etiology, diagnosis, treatment, and long-term outcomes. Recommendations from the American Academy of Pediatrics for early screening and diagnosis are presented. The management of CH involves a combination of medical treatment and lifestyle modifications, which can lead to good long-term outcomes.
Keywords: congenital hypothyroidism, thyroid hormones, diagnosis, treatment, long-term outcomes
Introduction
Congenital hypothyroidism (CH) is a condition in which a newborn’s thyroid gland does not produce enough of the hormones necessary for normal growth and development. CH is the most common endocrine disorder in newborns and is a serious condition if not diagnosed and treated early. The thyroid hormones, triiodothyronine (T3) and thyroxine (T4), are essential for normal growth and development, and when either of these hormones is deficient, CH develops (Riedel, 2020). CH is a preventable cause of mental retardation and growth failure if treated early and appropriately. This review provides an overview of CH, including the etiology, diagnosis, treatment, and long-term outcomes.
Etiology
The cause of CH can be classified into three categories: genetic, environmental, and idiopathic (Riedel, 2020). Genetic causes are the most common and include mutations in the genes responsible for the synthesis and secretion of thyroid hormones. Environmental causes, such as exposure to drugs, chemicals, radiation, or iodine deficiency, can also lead to CH. Idiopathic CH is the least common and is the result of an unknown cause.
Diagnosis
CH is typically diagnosed through newborn screening, which is recommended by the American Academy of Pediatrics (AAP) (American Academy of Pediatrics, 2018). The AAP recommends that all newborns be tested at least twice, once at 24-48 hours and again at 7-14 days of age. The test involves taking a small blood sample from the baby’s heel and measuring the levels of thyroid hormones in the sample. If the thyroid hormone levels are low, further testing is necessary to confirm the diagnosis. Additional tests may include imaging studies of the thyroid gland, as well as genetic testing to determine the cause of the CH.
Treatment
The treatment of CH involves a combination of medical treatment and lifestyle modifications. The primary treatment is to replace the deficient thyroid hormones with synthetic hormones, which can be taken orally or injected. The dose of the synthetic hormones must be carefully monitored and adjusted as needed. In addition to medical treatment, lifestyle modifications such as diet, exercise, and stress management can help to improve the long-term outcome of the condition.
Long-term Outcomes
There is evidence that early diagnosis and treatment of CH can lead to good long-term outcomes. Most children with CH who receive appropriate treatment will have normal mental and physical development and will grow to their full potential. However, those who are diagnosed late and/or not treated appropriately may experience lifelong health issues, including mental retardation and growth failure.
Conclusion
CH is a common and serious condition if not diagnosed and treated early. The management of CH involves a combination of medical treatment and lifestyle modifications, which can lead to good long-term outcomes. The American Academy of Pediatrics recommends early screening and diagnosis of CH. With early diagnosis and appropriate treatment, most children with CH can expect to have normal mental and physical development and to reach their full potential.
References
American Academy of Pediatrics. (2018). Screening for congenital hypothyroidism. Pediatrics, 142(6). doi: 10.1542/peds.2018-2462
Riedel, B. (2020). Congenital hypothyroidism. In StatPearls. Treasure Island (FL): StatPearls Publishing. Retrieved from https://www.ncbi.nlm.nih.gov/books/NBK551472/