Congenital hypothyroidism: A theoretical approach

Abstract

Congenital hypothyroidism (CH) is a rare endocrine disease that manifests chronically and insidiously in children. Historically, HC is linked to regions with high rates of malnutrition, lack of prenatal care, and late diagnosis. In addition, studies show that the risk is higher in female children, high maternal age, prematurity and the birth of twins. The disease is based on the alteration of thyroid hormone or Thyroid Stimulating Hormone (TSH) levels, so the main complications are in bone development, which can lead children to short stature and growth retardation, and in neurological development, which can lead to mental retardation. Thus, the delay in diagnosis, especially until the second or third month of life, can impair the physical and cognitive development of the newborn, generating irreversible complications. Newborn screening is challenging, as a significant portion of children appear to be normal at birth. It relies on a heel prick to detect high TSH levels and low thyroxine (T4) or free T4 levels. After diagnosis, treatment is instituted, through hormone replacement with levothyroxine, to avoid irreversible deficits and long-term metabolic complications. Treatment is also challenging, as hormone replacement is regularly adjusted based on the child's growth and development to keep hormones within the age range, which makes regular medical follow-up essential.