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Be careful about Hyperthyroidism

The two hormones, thyroxine or T4 and thyronine or T3 secreting gland situated in the lower part of neck, below the Adam’s apple is the thyroids. These hormones linked with the important metabolic processes in the body. Increase in this hormone production is called hyperthyroidism, whereas a decrease in thyroid hormone production results in a condition called hypothyroidism.  These hormones also affect the heart, muscles, bones and cholesterol.

If hyperthyroidism is untreated, it can lead to atrial fibrillation or abnormal heart rhythm, heart failure, osteoporosis or bone thinning and neuropsychiatric problems. Untreated hypothyroidism can lead to fatigue, weight gain, mental slowing, heart failure, and increase in cholesterol levels. 

Thyroid Levels

Test Lab Low Optimal Range Lab High

TSH 0.5 1.3-1.8 5.0

Free T4 0.8 1.2-1.3 1.8

Free T3 230 320-330 420

Free T3* 2.3 3.2-3.3 4.2

The TSH level with a high FT4 level and a high FT3 level indicate hyperthyroidism. This cause many diseases, like Graves’ diseases which is the most common one.  The patient of hyperthyroidism may lose weight quickly, have a rapid heartbeat, sweat a lot and moody. Some patients may not show any symptoms and the problems is diagnosed accidently. The condition can be easily treated using anti-thyroid medications, radioactive iodine or surgery.  Untreated hyperthyroidism can lead to serious complications of the heart and bone.

Reasons for Hyperthyroidism

There are many factors involved with the development of hyperthyroidism. This includes Graves’ disease, multi-nodular goiter, solitary thyroid nodule, thyroiditis, excessive iodine, intake of large doses of thyroid hormone.

Symptoms of Hyperthyroidism

An enlargement of thyroid gland in the neck or goiter, weight loss, nausea and vomiting, diarrhea, breathlessness on exertion, increased sweating, heat intolerance, loss of hair, menstrual disorders, exophthalmos (a condition when the eyes have a straight look protruded unusually out), fatigue, irregular pulse, palpitations and difficulty in sleeping are the symptoms of hyperthyroidism.

Diagnosis of Hyperthyroidism

Clinical diagnosis helps to identify hyperthyroidism. Physical examination reveals, enlarged thyroid gland, increased heart rate, elevated systolic blood pressure. 

Treatment for Hyperthyroidism

The treatment depends on the cause and severity of the symptoms. Anti-thyroid drugs, works best when the symptoms of the disease are mild. The patient has to take them at the same every day. If it does not work well, radioactive iodine is the next option. 

Radioactive iodine destroys part of the thyroid gland, which helps to stop the excess production of hormones; this substance doesn’t harm other parts of the body.

Another option is removal of thyroid gland through surgery. Such patient has to take thyroid hormone replacement pills for life time. 

Pregnancy and hyperthyroidism

During pregnancy human chorionic gonadotropin (HCG) hormone is produced. This hormone is detected through pregnancy tests.  HCG hormone has mild thyroid stimulating effects which can cause some symptoms of hyperthyroidism. It can occur in 10-20% of normal pregnant women.  Pregnancies complicated by uncontrolled hyperthyroidism may result in spontaneous abortion, preterm labor or low birth weight babies.

Prevention of Hyperthyroidism

Iodine intake can worsen hyperthyroidism. Vitamin B12, Zinc and Iron-rich foods should be included in the diet because hyperthyroidism patient are more likely to suffer such nutrient deficiencies. Protein rich food like salmon, nuts and legume manage excessive weight loss. Hyperthyroidism may lead to osteoporosis. Calcium rich food helps to prevent complications. Regular exercise, avoiding alcohol and smoking help to improve the overall health. 

Congenital Hypothyroidism

Congenital Hypothyroidism (CHT) or cretinism is the partial or complete loss of function of the thyroid gland that is present at birth. Babies with congenital hypothyroidism have lower levels of important hormones. It occurs one in every 3,000-4,000 births and in almost 90% of the cases, it persists throughout life and will require regular replacement with thyroid tablets.

There are two type of CHT, one is permanent and other is temporary.  In both cases thyroid gland is missing or poorly developed. Majority of CHT are permanent type.  In some cases due to genetic issues the thyroid hormone production itself maybe impaired and in some others the pituitary gland or hypothalamus, the central controlling gland may not function adequately.

Temporary hypothyroidism in infants occurs in about 20% of overall cases, the cause of it is unknown. Pregnant women with underactive thyroid are at increased risk for not only delivering CHT babies, but also premature and low birth weight babies. 

Causes of congenital Hypothyroidism

Maternal hypothyroidism treatment with anti-thyroid drugs during pregnancy may cause temporary hypothyroidism in babies. Commonest cause of congenital hypothyroidism all over the world is the deficiency of Iodine.  Absence or reduced size of thyroid gland, thyroid hormone production deficiency, improper stimulation of thyroid gland by the pituitary gland are the causes of congenital hypothyroidism.

Symptoms and Signs of Congenital hypothyroidism

Less activity and more sleep, feeding difficulty, weak cry, constipation, puffy face, and poor muscle strength, prolonged jaundice after birth, protruding tongue, and distended abdomen are the symptoms and signs of congenital hypothyroidism.  

Diagnosis of Congenital Hypothyroidism

The decreased levels of serum thyroid hormone (free T4) and elevated levels of thyroid-stimulating hormone (TSH) confirm primary hypothyroidism. In European countries the sample of the baby’s blood is taken from the heel before discharge and tested for levels of T3, T4, TSH. If the T3 and T4 levels are low and TSH is high, the doctor will refer the infant to pediatric endocrinologist to confirm the diagnosis and begin treatment. 

Thyroid scanning can provide information about the cause of congenital hypothyroidism. A technetium thyroid scan is used to detect a structurally abnormal gland. A radioactive iodine scan will help to identify congenital absence of gland. 

Instead of radioactive scanning, Ultrasound study can be done. But it will not reveal ectopic thyroid tissue that is visible in radioactive scans.

To find the distal femoral epiphysis, a lateral radiograph of the knee may be taken. Before the introduction of hormone measurements, radiograph was used as a diagnostic test for congenital hypothyroidism. 

Treatment for Congenital Hypothyroidism

Early diagnosis is needed to start treatment as soon as possible. A screening test for a newborn should include tests related to the thyroid gland. If you are going for thyroid replacement treatment you should inform the doctor before the delivery.

Diagnosis before 2 weeks of age and bring the levels of thyroid hormone levels in blood to normal before 3 weeks of age, includes in optimal care. If it is not done on time there are some risks in the normal development of the baby. 

Congenital hypothyroidism is controlled by the thyroid hormone in the form of an oral pill called levothyroxine. Most babies require a lifetime treatment.  It is essential that the tablet is administered daily mixing with a small amount of water, formula or breast milk without failing. The regular check-ups with a paediatric endocrinologist will help to ensure normal growth and brain development of baby. 

Prevention of Congenital Hypothyroidism

The early diagnosis and institution of therapy for congenital hypothyroidism is important treatable causes of mental retardation. Between 2-4 days of birth, neonatal screening of T3, T4, and TSH should be done. Otherwise testing should be done within 7 days of birth before the baby is discharged. 

Dietary iodine supplementation in iodine-deficient endemic areas helps prevent endemic cretinism.  The dietary iodine deficiency is the most common preventable cause of brain damage worldwide. The mothers using anti-thyroid drugs for hyperthyroidism during pregnancy are at high risk for development of congenital hypothyroidism. In the same way babies’ mothers who have undergone radioactive treatment for thyroid cancer during pregnancy are also at risk for development of congenital hypothyroidism. Such babies should be regularly monitored and followed slightest signs of hypothyroidism.

Health tips

Intake of iodine supplemented salt is preferable to prevent hypothyroidism caused by iodine deficiency.  Don’t neglect symptoms such as failure to feed properly, constipation, weak cry, or decreased activity of newborn. Contact a paediatrician immediately for further investigation.