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Hyperthyroidism or Thyrotoxicosis
Hyperthyroidism is characterised by increased thyroid hormone synthesis and
secretion from the thyroid gland, whereas thyrotoxicosis refers to the clinical syndrome of excess circulating thyroid hormones, irrespective of the source [3].
Clinical Manifestations of Thyrotoxicosis
Increased metabolic rate, intolerance to heat along with increase in skin temperature
and sweating, hair loss/thinning, increased appetite but weight loss, increased thirst,
diarrhoea, nervousness, tremors, tachycardia, psychosis, osteoporosis and cardiovascular abnormalities are common manifestations of thyrotoxicosis [3].
Aetiology of Thyrotoxicosis
Thyrotoxicosis is classified in certain types but two types are commonly used in the
literature, i.e. Grave’s disease (diffuse toxic goitre) and toxic nodular goitre [3].
Grave’s Disease
It is an autoimmune condition caused by the abnormal production of IgG immunoglobin (also known as thyroid receptor antibodies TRABs). IgG mimics the action
of TSH at its receptors by causing the increased activation of receptors and ultimately an augmented secretion of TH. Maternal TRABs can cross placenta resulting in transient neonatal thyrotoxicosis [1, 3].
Toxic Nodular Goitre
It is common in elder females presented with nodular goitre. T3/FT3 (FT3: Free T3)
is strikingly elevated and FT4 (FT4: free T4) becomes normal/moderately elevated
in this condition [1, 3].
Other Thyroid Disorders
Simple Non-Toxic Goitre
Simple non-toxic goitre is a condition associated with prolonged dietary deficiency
of iodine causing elevation in the plasma level of TRH. This may eventually leads
to enlargement of thyroid glands with normal levels of thyroid hormones except in
severe iodine deficiencies [2].
Y. H. Khan et al.
Hyperthyroidism or Thyrotoxicosis
Hyperthyroidism is characterised by increased thyroid hormone synthesis and
secretion from the thyroid gland, whereas thyrotoxicosis refers to the clinical syndrome of excess circulating thyroid hormones, irrespective of the source [3].
Clinical Manifestations of Thyrotoxicosis
Increased metabolic rate, intolerance to heat along with increase in skin temperature
and sweating, hair loss/thinning, increased appetite but weight loss, increased thirst,
diarrhoea, nervousness, tremors, tachycardia, psychosis, osteoporosis and cardiovascular abnormalities are common manifestations of thyrotoxicosis [3].
Aetiology of Thyrotoxicosis
Thyrotoxicosis is classified in certain types but two types are commonly used in the
literature, i.e. Grave’s disease (diffuse toxic goitre) and toxic nodular goitre [3].
Grave’s Disease
It is an autoimmune condition caused by the abnormal production of IgG immunoglobin (also known as thyroid receptor antibodies TRABs). IgG mimics the action
of TSH at its receptors by causing the increased activation of receptors and ultimately an augmented secretion of TH. Maternal TRABs can cross placenta resulting in transient neonatal thyrotoxicosis [1, 3].
Toxic Nodular Goitre
It is common in elder females presented with nodular goitre. T3/FT3 (FT3: Free T3)
is strikingly elevated and FT4 (FT4: free T4) becomes normal/moderately elevated
in this condition [1, 3].
Other Thyroid Disorders
Simple Non-Toxic Goitre
Simple non-toxic goitre is a condition associated with prolonged dietary deficiency
of iodine causing elevation in the plasma level of TRH. This may eventually leads
to enlargement of thyroid glands with normal levels of thyroid hormones except in
severe iodine deficiencies [2].
Y. H. Khan et al.