450 likes | 954 Views
بسم الله الرحمن الرحيم. THYROID GLAND By Dr. Ghada Ahmed Lecturer of pathology Benha Faculty of Medicine. Normal thyroid. Hypothalamic-pituitary-thyroid axis. Hypothyroidism. Primary hypothyroidism T hyroiditis : Hashimoto autoimmune thyroiditis D ietary iodine deficiency.
E N D
بسم الله الرحمن الرحيم THYROID GLAND By Dr. Ghada Ahmed Lecturer of pathology Benha Faculty of Medicine
Hypothyroidism • Primary hypothyroidism • Thyroiditis :Hashimoto autoimmune thyroiditis • Dietary iodine deficiency. • Drugs that block thyroid hormone synthesis. • Thyroid surgery or radiation. • Secondary hypothyroidism: usually caused by TSH deficiency.
Hypothyroidism Clinical effects: • Cretinism
Hypothyroidism • Myxdema
Hyperthyroidisim (Thyrotoxicosis) • Primary hyperthyroidism: • Graves disease (autoimmune)(85% of cases). • Goiter: Hyperfunctionalmultinodular goiter. • Adenoma: Hyperfunctional adenoma of thyroid. • Secondary hyperthyroidism: • Pituitary adenoma. • Inappropriate intake of exogenous hormone (as a treatment for hypothyroidism)
Hyperthyroidisim (Thyrotoxicosis)Clinical features: • Cardiac manifestations • Ocular manifestations • Neuromuscular system • Skin • Gastrointestinal system • Low serum TSH with increased free serum T4.
Thyroiditis Types: • Hashimoto thyroiditis • Subacute (granulomatous) thyroiditis • Reidel thyroiditis
Subacute (granulomatous) thyroiditis • History of upper respiratory tract infection
Reidel thyroiditis • Rare disease. • Unknown etiology. • Extensive fibrosis of thyroid and surrounding neck structures.
Graves disease Pathogenesis • It results from autoantibodies to TSH receptor, (long acting thyroid stimulator (LATS)) activate the surface receptors for TSH on thyroid epithelium.
Graves disease • Pathogenesis • Gross picture • Microscopic picture
Graves disease • Clinical effects
Goiters • Definition • Goitrogens
Diffuse nontoxic (simple) goiter • Endemic form • Sporadic form • Morphology: • Hyperplastic stage • Colloid involution stage • Most patients are clinically euthyroid.
Multinodular goiter (Nodular colloid goiter) • Repeated cycles of stimulation and involution of a diffuse goiter • Pressure symptoms • It may be non-toxic or may induce thyrotoxicosis (toxic multinodular goiter).
Tumors of the thyroid gland • A) Benign tumors: Follicular adenoma • B) Malignant tumors Thyroid carcinoma
Benign tumorsthyroid follicular adenoma • Microscopic picture: various histologic subtypes according to degree of follicle formation and colloid content: • 1- Colloid adenoma (macrofollicular). • 2- Fetal adenoma (microfollicular). • 3- Embryonal adenoma. • 4- Hϋrthle cell adenoma. • 5- Atypical adnoma.
Thyroid follicular adenoma • Clinical effects:
Thyroid carcinoma • Papilary carcinoma • Follicular carcinoma • Medullary carcinoma • Anaplastic carcinoma