27 Sep What mums need to know about thyroid disease
With regular vaccinations, baby weigh-ins, the sleepless nights and constant feedings, mums the world over would agree that they have enough on their plate. However, many South African parents remain unaware of thyroid disease and its impact on their little one.
An under-functioning thyroid gland (hypothyroidism), is a condition that can affect new born babies, and if undetected and left untreated, it can impact your child’s development with varying degrees of severity. Below is some insight on thyroid disease from Merck, the global pharmaceutical company headquartered in Germany.
Why is the thyroid gland important?
It may be just a small, butterfly-shaped gland in your neck, but the thyroid gland produces hormones that are essential to the body’s metabolism. It is important for the physical growth, maturation of the central nervous system and skeleton.
What causes hypothyroidism in babies?
There are many causes of hypothyroidism, the most relevant being congenital hypothyroidism, i.e. when an infant is born without a thyroid gland or if the gland cannot manufacture the thyroid hormone for a number of reasons. In areas with iodine deficiency, infants may also be prone to hypothyroidism. Since 1995, table salt has been iodized in South Africa, to combat hypothyroidism due to iodine deficiency.
In addition, if a mother suffers from thyroid disease during pregnancy, this may impact her unborn foetus and the newborn baby. Therefore it is important that a foetal ultrasonography is performed and the newborn baby is evaluated by a paediatrician.
What are the symptoms?
Undiagnosed babies affected with hypothyroidism show a variety of symptoms, including decreased activity, a large fontanelle, poor feeding and low weight gain, small stature or poor growth, delayed developmental milestones, jaundice, constipation, and a hoarse cry. The features are generally not present at birth and only develop after the first few weeks of life. Quite often, affected babies are initially viewed as ‘good’ infants, because they cry little (as they are inactive) and sleep a lot.
Affected newborns look totally normal at birth. The physical signs only develop gradually by which time the child’s development is irreversibly affected. Obvious physical signs are often missed as they are very subtle. These include coarse facial features, a big tongue, an umbilical hernia (when part of the intestine protrudes through the umbilical opening), mottled skin that is cool and dry, and anaemia.
“Testing for hypothyroidism in infants is as simple as a heel-prick test usually after 2 to 3 days of age,” says Dr Kiran Parbhoo, paediatric endocrinologist at the Chris Hani Baragwanath Academic Hospital. “The test is quick and simple, and yields results quickly, equipping doctors and supporting healthcare professionals to intervene early by setting up a treatment regime.” An alternative to heel prick testing is the testing of cord blood at birth. The advantage of heel prick testing however, is that it may be possible to screen for other inborn errors (as is the case in many developed countries). Detecting and managing inborn errors is cost effective as the treatment of these conditions is expensive if the condition is diagnosed later in life.
The risk of non-treatment
Failure to diagnose and treat hypothyroidism in an infant could lead to growth problems, heart problems, and if left untreated, severe intellectual disability.
Babies with congenital hypothyroidism on newborn screening programmes can be treated by simply administering thyroxine, which is delivered via crushed tablets included in breast milk or formula in infants, or swallowed by children as they grow older. By screening and treating congenital hypothyroidism one can prevent mental retardation.
Newborn screening for congenital hypothyroidism has been practised in the USA and most developed nations for the past fifty years. The United Nations has advocated for children to enjoy the highest standard of health in the Rights of the Child. In this context, screening for congenital hypothyroidism is being and should be more widely adopted.