Hyperthyroidism is the deranged condition of the body caused due to hyper functioning of thyroid gland causing excess production of thyroid hormones.

Since hormones produced by the thyroid gland influence the body’s metabolism, excess production due to any cause will lead to increased metabolism.

Most common cause for hyperthyroidism is Grave’s disease. It is an auto immune disease (antibodies directed to body’s own antigens), affecting middle aged people, more of women than men.

Other autoimmune malady like Hashimoto’s thyroiditis can cause hyperthyroidism in early stages but with advancement of disease, the gland tissue is damaged resulting in hypothyroidism.

Inflammatory conditions of the thyroid, i.e. thyroiditis are yet another cause for hyperthyroidism. About 7% women can develop hyperthyroidism after delivery.

Drug like thyroxin (used to treat hypothyroidism), when given for long without monitoring can result in hyperthyroidism.

Amiodarone a drug used for cardiac arrhythmias mimics thyroid function and can induce hyperthyroidism. It is said that if ground beef consumed has the thyroid gland crushed with it, can be a source of hyperthyroidism.

Apart from this, tumours in the thyroid or pituitary gland also affect functioning of the thyroid gland causing hyperthyroidism.

Increased metabolism will typically manifest as sense of restlessness, feeling hot, palpitations, tremors, muscle twitching, muscle and joint pain. In spite of eating well the affected person tends to loose weight due to the hyper metabolic state.

This is because metabolism becomes faster than the body can assimilate.   Intestinal motility is increased   causing recurrent diarrhoea.

All these combine to weaken the strength of a person thus reducing his work efficiency also.

There is protrusion of the eye balls with retraction of the eye lids giving an appearance of, "big sized eyes”. Eye signs are more common with Grave’s disease. Swelling in front of neck known as goitre is present with thyroid disorders.

Diffuse goitre is common with Grave’s disease, while a nodular goitre is suggestive of malignancy.  Some cases of autoimmune disease may develop swelling of feet.

If the thyroid gland is much enlarged it can cause compression of the wind pipe and food pipe, resulting in breathlessness and difficulty in swallowing, thus adding on the morbidity.

In advanced cases, hyperthyroidism can lead to atrial fibrillation (chaotic excess beating of the heart) and heart failure.

This happens because the heart is put under great stress.    Patients may suffer from sexual impotence, excess menstrual bleeding.

Some people may develop neurological dysfunction mimicking cerebral or spinal tumours. Smoking and alcohol consumption is known to aggravate the clinical problem.

In presence of a goitre or eye signs it is easy to diagnose hyperthyroidism. In other cases, a high index of suspicion is needed for diagnosing it. Because the patient may have no other clinical features except that of an anxiety state.

A person may receive tranquilizers and sedatives with counselling for many months to years for a presumed anxiety neurosis, before the physician realizes that in fact he has hyperthyroidism. 

Diagnosis of hyperthyroidism is established by doing a blood test to assess the level of thyroid hormones in the blood.

Ultrasound and C.T. scans can aid in detecting mild thyroid enlargement in case of absence of a goiter. Biopsy of the thyroid gland is needed if there is a suspicion of malignancy.

Treatment is by antithyroid drugs ( eg. Carbimazole), which suppress excess thyroid function. Surgery or radiotherapy is used for malignancy or severe cases.

Surgery is followed by drugs with monitoring of thyroid functions clinically and by test.

Other drugs are used to provide palliative relief to the patient depending on his problem.  Caution is needed to avoid inducing hypothyroidism (deficiency of hormones) through treatment.

A healthy and disciplined life style can help in reducing the suffering due to hyperthyroidism.

Specialist internal medicine – Ruhengeri hospital

E-mail – rachna212002@yahoo.co.uk