1. THYROID DYSFUNCTION

5. Grave’s disease (10) Autoimmune - activating AB’s to TSH receptor
High concentrations of circulating thyroid hormones
Weight loss, tachycardia, tiredness
Diffuse goitre - TSH stimulating growth
Opthalmopathy and dermopathy

6. Hyperthyroidism Level of the defect (1, 2, 3) Thyrotoxicosis
Graves’ disease
Toxic Adenoma
Toxic Multinodular Goiter
Chronic Thyroiditis

7. Exophthalmos
bilateral exophthalmos (bulging eyes) is typical marker of autoimmune Graves' disease (hypethyreoidismus)
Thyroid-stimulating autoantibodies mimic the action of TSH; they are directed against the thyrotropin receptor autoantigen (TSHR) on the thyroid follicular cell and similar receptors throughout the body and they may also react with these autoantibodies
Subset of orbital fibroblasts is rich in this membrane receptor
After stimulation the orbital fibroblasts are capable of differentiating into adipocytes and thus increase orbital adipose tissue

8. Symptoms and signs of hyperthyroidism

9. Hypothyroidism 1, 2, 3 Newborn Cretinism Lack of myelination
Children
Retarded Growth
Disproportionate

11. Symptoms and signs of hypothyroidism

12. Myxedema (myxoedema)
Hypothyroid myxedema is specific form of skin edema
Increased activity of connective tissues leads to increased deposition of components of extracellular matrix (mainly glycosaminoglycans, proteoglycans) which retains large amounts of sodium ions and water
Stimulation of fibroblasts is caused by increased amount of TSH which is able to bind to some membrane receptors and by this way it activates biosynthesis of extracellular matrix

14. Thyroid hormone resistance
Mutation of the receptor.
Characterized by high blood levels of both TSH and Thyroid hormones

15. Non-toxic goiter
Iodine deficiency

16. Thyroiditis

17. Hashimoto’s (1o)
Autoimmune - AB’s destruction of thyroid gland
Low concentrations of thyroid hormones
Lethargy, intolerance to cold
Lack of growth and development
Diffuse goitre - lymphocytic infiltration of gland + TSH stimulated growth

18. Euthyroid Syndrome
Patient presents and complains of hypothyroid type symptoms
Levels of Thyroid hormones (free & total), & TSH in low normal range.
May be due to a 5’-deiodinase deficiency

19. Euthyroid Sick Syndrome
Occurs in acute and chronic illness.
Derangements of thyroid hormone levels are due to alterations in peripheral metabolism of T4 and binding of T4 to TBG. Fasting or illness also decrease the magnitude of TSH pulsations.
Low T4 belays poor prognosis.

20. Euthyroid Sick Syndrome
Severity of Illness
Free T4
Free T3
Reverse T3
TSH
Mild
Normal
Reduced up to 50%
Increased up to twofold
Moderate
Increased
Reduced up to 90%
Increased up to several fold
Severe
Reduced
Almost undetectable
Variable

22. Evaluating thyroid function
The serum TSH is the best initial test of thyroid function. The latest generation of this assay has high sensitivity and is an excellent screening tool for those patients with a low pretest probability of thyroid disease.

23. TSH of 0.5-4.0 mU/L is highly diagnostic for normal thyroid function.
A high TSH (>5.0 mU/L is an indication for further testing,such as a free T4 (FT4) determination or a free thyroxine index (FTI)
A patient who has a TSH in the gray zone (4.1–5.0 mU/L) is very likely to develop hypothyroidism and should be screened regularly

40. Thyroid hormones in various disorders
Free T3
Free T4
TSH
condition
High
V.high
Undetectable
Primary hyperthyroid
v.High
Normal
T3 thyrotoxicosis
Increased
Secondary hyperthyroidism N
Low
Subclinical hyperthyroidism

41. Thyroid hormones conc. In various Disorders
Free T3
Free T4
TSH
Condition
or N
Thyroid H Resistance
Primary hypothyroidism
Secondary hypothyroidism