DR Medhat MRCP

Subclinical Hyperthyroidism
- It is defined as:
Normal T3 – T4
Low TSH (usually < 0.1 mu/l)
Causes:
Toxic nodular goitre, particularly in elderly females.
Excessive thyroxine may give a similar biochemical picture.
The importance in recognising subclinical hyperthyroidism lies in the potential
effect on
1. The cardiovascular system (atrial fibrillation).
2. Bone metabolism (osteoporosis).
3. It may also impact on quality of life and the likelihood of dementia.
Management:
1) TSH levels often revert back to normal - therefore levels must be persistently low to
warrant intervention
2) A reasonable treatment option is a therapeutic trial of low-dose antithyroid agents
for approximately 6 months in an effort to induce a remission.
Hypothyroidism
Definition : Deficiency of thyroid hormones (T3 &T4)
‣ If neonatal or infantile
‣ If during childhood
‣ If in adult
Cretinism.
Juvenile myxoedema.
Myxoedema.
In European countries primary atrophic hypothyroidism is the most common cause
of hypothyroidism
In North America Hashimoto's thyroiditis is the most common cause of
hypothyroidism