Congenital hypothyroidism can lead to autism
In this era of digitalisation one of the major obstacles for development of any developing nation is handicapped (mental and physical) manpower. But, by raising awareness for proper nutrition and treatment for the pregnant mother and new born babies, a significant number of physical and mental disorders of infants can be avoided.
The CH affected babies would grow poorly and will face delay in their development. By several years of age, they would display the recognisable facial and body features of elfin (cretinism) with an IQ level below 80 in most cases.
Thyroid hormones are mainly tri-iodothyronine (T3) and thyroxin (T4) which are secreted from the butterfly shaped thyroid gland located at the neck just below the Adam's apple. The deficiency of these hormones is called hypothyroidism and when this deficiency present in new born babies that is called CH. If CH remains untreated until 3 months after birth, the result would be the mental and physical retardation of the child. Brain development is absolutely dependent on normal thyroid hormone levels. The foetus and the infants are neurologically vulnerable due to the incomplete brain development in humans at birth.
Around the world approximately 1 in 4,000 newborn babies has a severe deficiency of thyroid function but according to the research paper of 'Institute of Nuclear Medicine, Dhaka, Bangladesh' incidence rate in Bangladesh is approximately 1: 1,300, which is alarming.
Infants born with congenital hypothyroidism may show no effects, or may display mild effects that often go unrecognised as a problem such as excessive sleeping, reduced interest in nursing, poor muscle tone, low or hoarse cry, infrequent bowel movements, exaggerated jaundice and low body temperature. If foetal deficiency is severe because of complete absence (athyreosis) of the gland, physical features may include a larger anterior fontanelle, persistence of a posterior fontanelle, an umbilical hernia and a large tongue (macroglossia).
Nearly all cases of congenital hypothyroidism can be detected by the newborn screening programme. These are based on measurement of TSH (thyroid stimulating hormone, which is secreted from pituitary gland and initiate thyroid hormone formation) or thyroxine (T4) on the second or third day of life.
If the TSH is high, or the T4 is low, the infant's doctor and parents are called and a referral to a paediatric endocrinologist is recommended to confirm the diagnosis and initiate treatment in the developed country. Often a technetium (Tc-99m pertechnetate) thyroid scan is performed to detect a structurally abnormal gland. A radioactive iodine (RAIU) exam will help differentiate congenital absence or a defect in organification (a process necessary to make thyroid hormone). Congenital hypothyroidism can also occur due to genetic defects of thyroxine or tri-iodothyronine synthesis within a structurally normal gland.
However, the goal of newborn screening programme is to detect and start treatment within the first 1–2 weeks of life. Treatment consists of a daily dose of thyroxine, available as a small tablet. The generic name is levothyroxine, and several brands are available. The tablet is crushed and given to the baby with a small amount of water or milk. Within a few weeks, the T4 and TSH levels are rechecked to confirm that they are being normalised by treatment. As the child grows up, these levels are checked regularly to maintain the right dose. The dose increases as the child grows.
So the Government should emphasise on CH, for developing and raising awareness on newborn screening programmes and make the test at low cost and mandatory before leaving every child from the hospital.
The writer is a student of Pharmacy at Bangabandhu Sheikh Mujibur Rahman Science and Technology University (BSMRSTU).
E-mail: [email protected]