1. Thyroid Disease Dr John McDermott Consultant Endocrinologist
Connolly Hospital Blanchardstown
Hermitage Medical Clinic
Royal College of Surgeons in Ireland

2. Thyroid Hormones
Thyroid gland manufactures and releases thyroid hormones
Thyroid hormones are iodine containing amino acids
3, 5, 3’ triiodothyronine = T3
3, 5, 3’,5’ tetraiodothyronine = T4

3. Thyroid Hormones
‘Maintain the level of metabolism in the tissues that is optimal for their normal function’
Small amounts secreted continuously

4. Thyroid Hormones Deficiency or excess of thyroid hormones:
 wide and varied symptoms and physical signs involving any organ system

5. Thyroid Case 33 year old woman Gaining weight
Tired – busy job and 2 young children
Rows over thermostat

6. Thyroid Case T4: 6 (normal 9 – 22) TSH: 36 (normal 0.4 – 4)
Diagnosis: Hypothyroidism

7. Other symptoms of hypothyroidism
Constipation
Heavy periods
Cold dry skin, dry hair, hair loss
Muscle pains/stiffness

8. Hypothyroidism Joseph Fourier, a French mathematician
‘began to suffer from a strange disease, whose main effect was to render him extremely sensitive to cold….caused him to wrap up in many layers of heavy clothing, and live in a highly heated room from which he seldom ventured forth, even in summer heatwaves’.
Paul Strathern, Napoleon in Egypt

9. Treatment of Hypothyroidism
Thyroid hormone, T4 (Eltroxin)
Aim to abolish symptoms
Aim to achieve a high normal T4 and low-normal TSH
NB Pregnancy issues

10. Thyroid Case [2] 26 year old woman
Noticed prominence of right eye x 3 weeks
Increased appetite – but weight decreasing
Difficulty getting out of the bath

11. On Examination Pulse 120 regular Tremulous, sweaty hands
Enlarged, rubbery thyroid

12. Thyroid Case [2] T4: 37 (normal 8 – 22) TSH < 0.01 (normal 0.4 – 4)
Anti-TSH receptor antibodies ++
Diagnosis: Graves Disease causing hyperthyroidism, ophthalmopathy

13. Graves Disease Autoimmune condition
Antibodies against TSH receptor – stimulate excess thyroid hormone
Antibodies attack back of eye - proptosis

14. Treatment of Hyperthyroidism
Antithyroid drugs:
Carbimazole (Neomercazole)
Propylthiouracil (PTU)
Radioactive Iodine
Surgery - thyroidectomy

15. Radioactive Iodine Commonly prescribed treatment for hyperthyroidism
Orally-administered I131
Concentrated in thyroid gland, radiation destroys thyroid tissue

16. Radioactive Iodine
Precautions after dose
Long-term hypothyroidism

17. Surgery ‘Subtotal’ thyroidectomy Hypothyroidism
Potential other complications

18. Diseases of the Thyroid
Disorders of function:
Hyperthyroidism
Hypothyroidism
Disorders of structure:
Goitre
Thyroid nodules/cancer

19. Goitre Enlarged thyroid
Symptoms: Cosmetic concerns, obstructive symptoms
Toxic Multinodular Goitre: hyperthyroidism

20. Thyroid nodules 5% of population have palpable thyroid nodules
30-40% of popn have non-palpable nodules detectable on ultrasound
Thyroid cancer in 8% of palpable thyroid nodules
Differentiated cancers: slow growing, good prognosis

21. Thyroid nodules
Risk stratify: risk factors, u/s characteristics, hot or cold
Fine needle aspiration
Observation, surgery

22. Summary
Thyroid disease common but treatable, wide and varied complaints
Disorders of function: Hypo/Hyper, diagnosis TFTs
Disorders of structure: Goitre, nodules