Hypothyroidism is a condition that results from deficient production of thyroid hormones. In infants it is a rare condition but is not completely ruled out. According to statistics, out of 4000 infants only one may suffer from this condition. Hypothyroidism in infants and children can lead to mental and growth retardation. It is therefore necessary to detect and treat the disease in the early stage when suspected.
The disorder may manifest vey early in life as a congenital defect, or it may be acquired in older children after a period of apparently normal thyroid function. Though there are several reasons responsible for hypothyroidism in infants and children the treatment modality remains the same.
Causes Of Congenital Hypothyroidism In Infants
Hypothyroidism in infants can be classified into two categories, congenital hypothyroidism and acquired hypothyroidism.
- Congenital hypothyroidism
As the name suggests, the condition is present since birth. This form is more common in infants. At least 90 percent of infants suffering from hypothyroidism fall in this category. Majority of infants with congenital hypothyroidism have complete absence of thyroid gland or the gland may be in its rudimentary stage and under-active.
Often, the gland does not descend in its proper place and remains in ectopic location. Lastly the thyroid gland may fail to produce thyroid hormone for factors which remain unknown. The genes of both parents are involved in development of congenital hypothyroidism.
Congenital hypothyroidism in many infants has been found to be temporary. It can last from few days to few months, but after certain period the condition will improve. There may not be any need for further medication. Often transient CH prevails in mothers who are treated for hyperthyroidism or exposed to therapeutic dose of radio iodine when they are pregnant.
- Acquired hypothyroidism
Acquired hypothyroidism in infants and more commonly in older children may occur due to autoimmune thyroid disease. It is usually seen during early puberty period or during teenage life. Girls are affected more than the boys.
Symptoms Of Hypothyroidism In Infants
Hypothyroidism in newborns and infants remains unnoticed for months together in majority of cases as the signs and symptoms are not sufficiently developed. Therefore it is necessary to screen the child soon after birth and during the stage of infancy for hypothyroidism.
- Unusual prolongation of physiological jaundice.
- Feeding difficulty, lack of interest in feeding.
- Thick and large tongue leading to problems in breathing. There is noisy breathing and nasal obstruction.
- Face is puffy.
- During the first four weeks, the child may have choking spasm while feeding.
- Cries little and sleeps all the time.
- Abdomen is big with presence of umbilical hernia.
- The skin of hands and legs is cold.
After six month the picture is clearer:
- Stunted height with short extremities and large head.
- Delayed dentition and rapid decay of teeth.
- Bridge of nose is depressed.
- Swollen eyelids.
- The mouth remains open and tongue protrudes from it.
- The neck is short and thick.
- Hands are broad with short fingers.
- Lack of perspiration and skin is dry and scaly.
- Hair is coarse, brittle and scanty. Hairline reaches far down on forehead.
- Obstinate constipation which does not respond to laxatives.
- Hypotonic muscles.
Treatment Of Hypothyroidism In Infants
It is important to diagnose hypothyroidism in infants in the early stage. This is because treatment met during this stage may cause reversal of all symptoms and less damage.
Thyroid replacement hormone therapy remains the mainstay treatment. The medicine has to be taken daily. However, at frequent interval adjustment of dosage is necessary according to the blood reports.
The prognosis of infant hypothyroidism is good if the treatment is begun as early as possible in first few months. The child may have normal intelligence.
Untreated infant and children with severe hypothyroidism may have mental and growth retardation.
Since there are several tests available to detect and treat the disease in infancy, there is less chance of complications.