The World Immunization Week is here and I cannot emphasize more on what roles vaccines play to protect your child from dreadful diseases.
So, this post today is NOT about vaccines!
Read through this conversation between two sisters to discover what this essential prick is.
Avni is deeply excited. She awaits motherhood. At the same time, being a mom for the first time, she is embraced with so many questions and some anxiety. The baby is going to see this world in about 2 weeks.
To add to this excitement Avni’s elder sister Abha is here after 5 long years. She resides in the United States and landed this morning with her husband and 5-year-old son, Abhik.
As Abha arrives, Avni sees no bounds to her joy. The sun sets as the sisters share their gossips, gifts, and goodies. Both of them go to sleep as Avni shares plans about her to be born child.
The next morning, as Abhik is up, he brushes his teeth and comes up to his mom saying, “Momma, time for my pill.”
“Here it is, my love”, Abha unscrews the lid of a tiny bottle and picks up a pill. Abhik happily swallows the tablet and runs away to play.
Onlooking Avni is stunned. She says, “Abha, what is it? What’s that pill he just swallowed. Tiny Abhik, is he ill?
Abha smiles and says, “Darling, don’t worry. He is not ill. It’s his Levothyroxine tablet, he has to take it every day.”
Avni: “Leee…Vo…what.? Levothyroxine? What is it? Since when is he taking it?”
Abha explains, “Yeah, Levothyroxine. His supplements to replace his thyroid hormones. Abhik was diagnosed with congenital hypothyroidism and he is taking these pills since he was five days old.”
Avni is confused and has many questions arising in her mind. Abha is now well learned about her child’s condition and she goes on to clarify Avni’s queries.
“What is congenital hypothyroidism?”
“Every human being has an endocrine gland in the front of the neck, called the thyroid gland. It is a small butterfly-shaped organ that releases hormones called thyroxine and triiodothyronine, commonly called the T4 and T3 respectively.
These hormones have many important functions in the human body, which include metabolism (energy production), maintaining body temperature, growth and development, particularly of the brain and bone.
Congenital hypothyroidism is a condition of inadequate thyroid hormone production, due to various defects in thyroid gland present since birth. The manifestation could be in the newborn period or later based on the severity of the deficiency.
Thyroid hormone is crucial for brain development in fetal life and early childhood up to the age of 3 years. Thereafter, it is essential to ensure the proper growth of a child.”
Avni poses her next question, “How did you get to know that Abhik has congenital hypothyroidism?”
“Through the newborn screening test”, Abha continues, “When Abhik was born he looked perfectly alright; his weight was normal and he was feeding well.
We learnt that he had this disease only after the reports of his newborn screen came back and we received a phone call from the hospital staff on the 5th day.”
“What is this newborn screen?”
“Newborn screening is the testing done in all apparently healthy babies in the first few days of their lives for certain diseases or conditions.
In general, it is carried out for any disease which is
- Fairly common
- Asymptomatic in early stages
- Can be easily diagnosed through simple tests
- Can be easily treated
- Has got serious health implications if untreated, including fatality.
Such conditions may not manifest until they have caused irreversible damage to the child, such as irreversible brain damage in the case of congenital hypothyroidism.
There lies the importance of detecting them in the early stages, when the correct intervention can do wonders.
You must be aware of screening for breast cancer in elder females through self-breast examination and mammography; or
screening for type 2 diabetes by blood sugar tests in high-risk individuals like obese people.
Similarly, newborns are subjected to certain tests to screen for ailments that meet the above criteria, for example, diseases like congenital hypothyroidism, congenital adrenal hyperplasia, galactosemia, phenylketonuria, and others.”
Avni is now more curious, “How and when is the thyroid function test carried out in a newborn?”
“The test is carried out on the blood of the baby. And there are different ways in which the blood sample can be taken
- Cord blood: This is the blood drawn from the umbilical cord as soon as the baby is delivered, so this sample is taken right at birth.
- Heel prick of baby: The heel of the baby is pricked with a tiny needle and the drop of blood is taken on the special absorbent filter paper, which is sent to special testing laboratories.
- Venous sample: At some centers, the specialized methods may not be available. In such places, the pediatrician orders for the test to be carried out on about 1-2 ml of blood drawn from the baby’s vein and sent to private laboratories.
The ideal time to draw the heel prick and the venous sample is at 48-72 hrs after birth.
But in hospitals where mothers are discharged early, the sample may be taken just before discharging the mother home, so that no child misses the screen.
“What does thyroid function test comprise of?”, Avni is ready with her next question.
“The thyroid physiology is an interesting interplay of 3 hormones.
The thyroid gland that secretes T4 and T3, is in turn controlled by the master gland PITUITARY which secretes the Thyroid Stimulating Hormone (or the TSH).
When the thyroid is not functioning well and releasing small inadequate amounts of T4 and T3, the PITUITARY releases lots of TSH to stimulate the thyroid. This is called the feedback mechanism.
In the newborn screen by thyroid function test, either of TSH or T4 or both are tested initially. Different countries have different policies. Each has its disadvantages and advantages.
The screening tests are not diagnostic. They just filter out those who probably have the disease. Such babies with results that raise concerns are subjected to further tests for confirmation.
Avni wants to know more details. She now anticipates that her baby may also undergo such a test. She asks, “How did it all go about? What is the protocol?”
“Abhik’s heel prick sample was taken on the 3rd day and after a gap of 1 day, I received a call that informed me of the concern about his report. His TSH was grossly raised.
We immediately visited the hospital and after explanation, a venous sample was collected to carry out repeat TSH and T4 for confirmation.
The report was available by the same evening and Abhik was immediately started on treatment, as his reports suggested he had congenital hypothyroidism.
Meanwhile, the next day he was also subjected to a nuclear imaging study called the thyroid scan; along with ultrasonography of the thyroid gland.
These tests were done to know what has caused him to be hypothyroid. They were carried out smoothly and were barely of any botheration to the child.”
Avni was sad to learn these events, “Oh! Poor kid! He was subjected to these painful pricks right at his birth!!”
Abha interrupted and said, “Nope! Don’t sympathize. In fact, I am so happy that was done.
I find myself and Abhik fortunate that his disease was diagnosed right at the beginning and treatment started right away.
Congenital hypothyroidism is one of the commonest preventable causes of mental retardation.
Had the newborn screen been not done, the thyroid deficiency would have led to irreversible brain damage leaving him intellectually disabled.”
Today, Abhik is absolutely normal. He learnt to walk, talk, jump and play like any other kid at the expected age.
He is in his first grade and we as parents and his teachers are very proud of his performances in academic and extracurricular tasks.
Avni understands the role of the thyroid and the importance of thyroid function tests in the first days of life. She asks, “Is this test performed in all hospitals? Will my child be also subjected to this test? Tell me, sister. I am anxious”.
Abha pacifies her and says, “Don’t be anxious dear. In the United States and most developed countries, newborn screening is a government-driven policy.
Unfortunately, in India due to various reasons new born screening is not yet universal. It is being practised only in certain major centers.
But with increasing awareness, pediatricians are increasingly ordering the thyroid function test.
Therefore, the general public like you must be aware of such an illness and screening method so that you can rightfully discuss it out with the pediatrician who will care for your child after birth.
IF YOUR DOCTOR DOES NOT ORDER, YOU ASK FOR IT TO BE DONE.”
Just as Abha finishes speaking, Abhik runs in asking for his breakfast.
Meanwhile, you too take a break and come back to visit my next post as I educate you more on congenital hypothyroidism, its causes, treatment.
From the author: Why I write this post?
As a resident at my training institute, I was involved in the execution of the newborn screening program. The biggest challenge that we as doctors and our team faced was the ignorance and the mistrust of the new parents and the elder people at their homes. It was hard to convince them that not everything was alright with their apparently normal baby, especially in rural settings. The public viewed the team with a suspicion that this was being done for the monetary benefits of the hospital.
Awareness, accurate information, a few drops of blood, and your faith can help us to help you and your child.
Thank you for reading through this post. If you find the information useful, share it, and spread the awareness.
Do not hesitate to leave a comment or ask questions.