Congenital Hypothyroidism- Causes, Symptoms and Treatment

Hypothyroidism

Amongst various elements that are necessary for the human body to be developed and keep developing without any obstacles, iodine is one of the most necessary ones. It plays a key role in the creation of thyroid, which is one of the vital hormones required for the proper growth of various organs within the body, including the brain and the entire nervous system. Cretinism, which is what congenital hypothyroidism, is also called is generally a result of an extreme deficiency of iodine in the mother’s body, which tends to affect the development of the foetus within her too.

What is Neonatal Hypothyroidism?

Congenital hypothyroidism or neonatal hypothyroidism are two terms used to describe the same phenomena. When a newborn child is found to have a highly reduced quantity of thyroid being produced in its body, this is generally termed as neonatal hypothyroidism. In the rarest of the rare cases, some infants fail to develop thyroid at all, which requires intense medical intervention for the baby’s well-being.

Types of Congenital Hypothyroidism

Hypothyroidism effects on baby are dependent on the type of congenital hypothyroidism that the baby is suffering from.

1. Transient Congenital Hypothyroidism

In nearly a quarter of the cases of infants having hypothyroidism, their condition is usually temporary which is termed as transient hypothyroidism. It is mainly a result of a deficiency of iodine, which is generally due to reduced consumption of the same by the mother.

At times, there is the presence of an antibody termed as TSH-receptor blockers. These are a result of an autoimmune disease, present in the pregnant mother, which finds its way into the foetus as well. These receptors disturb the usual thyroid functioning in the newborn, resulting in neonatal hypothyroidism. However, this fades away in a few months as the infant’s immune system starts taking over and gets rid of these external antibodies.

External inputs play a role in this, too. Certain women who have high levels of thyroid during pregnancy might take drugs such as methimazole, which affects the foetus as well and causes hypothyroidism. In women with arrhythmia, taking medication such as amiodarone has a side-effect of elevating iodine levels in the body beyond the healthy limit, causing a temporary hypothyroidism to set in the baby. Both these conditions are temporary and the child’s thyroid functioning returns to normalcy after a couple of weeks or more.

2. Permanent Congenital Hypothyroidism

As the name suggests, this condition is not temporary and an infant suffering with permanent hypothyroidism needs treatment measures to be conducted throughout his life.

Such permanent hypothyroidism is usually a consequence of a biological factor. The thyroid gland in the child is either developed abnormally or is even located abnormally within the body. Such anomaly is termed as dysgenesis, and nearly 67% of the babies with hypothyroidism suffer from this problem.

A few other children face problems in either secretion of the hormone or synthesizing it within the body, even when the thyroid gland is free from anomalies. At times, the defect could be present in the transport system of these hormones, which rob various portions of the body from its presence. Problems related to the hypothalamus or the pituitary gland could also affect the thyroid gland, causing hypothyroidism to set in.

Causes of Congenital Hypothyroidism

Though the hypothyroidism in a newborn baby might be temporary or permanent, the reason behind it occurring is generally a result of certain major aspects.

  • Antibodies present in the mother’s body that carry out an autoimmune function against the thyroid hormone
  • Deficiency of iodine due to improper diet during pregnancy
  • Thyroid reducing medication consumed by the pregnant mother
  • Presence of thyroid hormones that fail to function in the right manner
  • Failure of the pituitary gland to signal a stimulation to the thyroid gland for producing hormones
  • A thyroid gland that is not properly developed or properly placed within the body

Symptoms of Hypothyroidism in Newborns

Generally, newborn babies may not even show signs of hypothyroidism if their levels are just an inch below normal. However, in babies with severely reduced levels of thyroid, the symptoms are pretty evident and usually manifest in the following forms.

  • A sluggish behaviour
  • Constant sleepiness even when hungry
  • A reduced height compared to other babies
  • A receded hairline
  • A floppy body with very little muscle mass
  • A possibility of jaundice due to yellowed eyes and skin
  • Crying hoarsely
  • Poor hair structure that is dry and unhealthy
  • Consistent constipation
  • Inability to feed properly resulting in repetitive choking

Diagnosis of Congenital Hypothyroidism in Babies

A doctor checking a crying infantUndertaking neonatal screening for congenital hypothyroidism can help detect cases with a possibility of such conditions well in advance. At other times, some diagnosis and tests might be required to arrive at a conclusive clarity.

  • Once the child is born, a quick test is undertaken right when the child is a couple of days old or so. A blood sample is acquired by gently pricking the baby’s heel and sent over for tests.
  • These tests are focused on measuring the presence and magnitude of thyroxine and thyroid stimulating hormones within the body.
  • A strong sign of hypothyroidism is noticed when the thyroxine T4 levels are reduced, but the stimulating hormone TSH levels are high. In such a case, a repeat test is conducted by taking a proper blood sample from the baby’s vein.
  • In this case, along with the previous factors, the levels of free T4 are checked as well. If these are found to be low as well, then congenital hypothyroidism is said to be confirmed.

With a strong diagnosis in place, doctors may choose to conduct various scans or ultrasounds to check for physical deformities in the thyroid gland and try to reason out the source of the condition.

Possible Complications

The absence of thyroid hormone in the right amount can affect a child, right from his intellectual ability as well as various physical aspects, too. Many children with hypothyroidism tend to have higher risks towards major issues.

  • The child could have difficulty paying attention in class or have trouble remembering things
  • He could fail to hear things properly or having issues regarding eyesight
  • The kid could start showing signs that are similar to an autistic child
  • Some kids suffer from mutism, which is the inability to speak at all
  • Constant tightness and restriction in the movement of muscles
  • Inability to walk properly

Treatment for Neonatal Hypothyroidism

The only way to treat a child suffering from neonatal hypothyroidism is to take efforts in bringing back the levels of thyroid hormone within the body. One of the major medications available on that front is the synthetically produced levothyroxine. This tablet ought to be crushed and mixed with the formula or the milk that is given to the baby. If in liquid form, it can also be given using a dropper or a syringe, directly in his mouth. Never mix this medication with soy milk, since the protein present in soy binds itself with the thyroid hormone, leaving nothing for the body to absorb.

Preventive Measures

To know how to prevent congenital hypothyroidism, the best way is to maintain good iodine levels during pregnancy itself. Always opt for iodised salt in your food items no matter what. In case you are under any medication to control your own thyroid levels or any other conditions, it is important to screen your child immediately after birth to check for hypothyroidism.

Congenital hypothyroidism can easily ruin a perfect childhood for a kid. Nevertheless, most cases revolve around the transient phase which fades away in a few weeks. For permanent hypothyroidism, your child requires love and care along with the treatment to be able to lead a happy and good life ahead.

Also Read:

Congenital Heart Diseases
Congenital Nystagmus in Infants
Neonatal Respiratory Distress Syndrome