Endocrine Tutorial

Hyperthyroidism

• Clinical features

Hyperthyroidism

• Clinical features– CVS: tachycardia, palpitations, atrial fib– CNS: tremor, anxiety, lability, insomnia– Heat intolerance; warm, moist, flushed skin– Weight loss with increased appetite

Hyperthyroidism

• Clinical features– CVS: tachycardia, palpitations, atrial fib– CNS: tremor, anxiety, lability, insomnia– Heat intolerance; warm, moist, flushed skin– Weight loss with increased appetite

• Causes

Hyperthyroidism

• Clinical features– CVS: tachycardia, palpitations, atrial fib– CNS: tremor, anxiety, lability, insomnia– Heat intolerance; warm, moist, flushed skin– Weight loss with increased appetite

• Causes– Graves disease– Exogenous thyroid hormone– Functioning multinodular goitre/thyroid adenoma– Thyroiditis– Secondary (hypothal/pituitary dysfunction)

Hypothyroidism

• Clinical features

Hypothyroidism

• Clinical features– CVS: bradycardia, cardiomegaly, pericardial effusion– CNS: slowed mental activity, apathy, fatigue, cretinism– Cold intolerance; cool skin; myxedema; hair loss– Weight gain with decreased appetite– Coarsening of features

Hypothyroidism

• Clinical features– CVS: bradycardia, cardiomegaly, pericardial effusion– CNS: slowed mental activity, apathy, fatigue, cretinism– Cold intolerance; cool skin; myxedema; hair loss– Weight gain with decreased appetite– Coarsening of features

• Causes

Hypothyroidism

• Clinical features– CVS: bradycardia, cardiomegaly, pericardial effusion– CNS: slowed mental activity, apathy, fatigue, cretinism– Cold intolerance; cool skin; myxedema; hair loss– Weight gain with decreased appetite– Coarsening of features

• Causes– Hashimoto thyroiditis– Surgery / Radiation / Drug-induced– Infiltration by tumour– Secondary (hypothal/pituitary dysfunction)

Graves disease

• Epidemiology – What type of people get Graves disease?

Graves disease

• Epidemiology – Women, 20-40 yrs, (M:F = 1:7)

Graves disease

• Epidemiology – Women, 20-40 yrs, (M:F = 1:7)

• Pathogenesis

Graves disease

• Epidemiology – Women, 20-40 yrs, (M:F = 1:7)

• Pathogenesis– Autoimmune disorder– Activation of thyroid by thyroid autoantibodies

• Anti-TSH R, anti-thyroglobulin, anti-T3/T4

– Associated with certain HLA types– Associated with other AI disorders

• Hashimoto thyroiditis, pernicious anaemia, rheumatoid arthritis

Graves disease

• Gross findings

– Mild symmetrical thyroid enlargement

– Eyes: exophthalmos, lid retraction, lid lag

– Skin: pretibial myxedema

Graves disease

• Microscopic findings

Graves disease Normal thyroid

Graves disease

• Microscopic findings

Hashimoto Thyroiditis

• Epidemiology

Hashimoto Thyroiditis

• Epidemiology– Women, 45-65 yrs, (M:F = 1:10 to 20)

Hashimoto Thyroiditis

• Epidemiology– Women, 45-65 yrs, (M:F = 1:10 to 20)

• Pathogenesis

Hashimoto Thyroiditis

• Epidemiology– Women, 45-65 yrs, (M:F = 1:10 to 20)

• Pathogenesis– Autoimmune disorder– Destruction of thyroid by thyroid autoantibodies

• Anti-TSH R, anti-thyroglobulin

– Associated with certain HLA types– Associated with other AI disorders

• SLE, pernicious anaemia, rh. Arthritis, Sjogrens, IDDM, Graves

– May cause transient hyperthyroidism in early stages– Gradual destruction and fibrosis hypothyroidism

Hashimoto Thyroiditis

• Gross findings

– Enlarged pale thyroid initially

– Atrophic thyroid eventually

Hashimoto Thyroiditis

• Microscopic findings

Hashimoto Thyroiditis

• Microscopic findings

Thyroiditis

• Painful– Infectious

• Adjacent sinusitis, mycobacteria, fungi

– Subacute (granulomatous)• Post viral

• Painless– Hashimoto’s– Fibrous

• Fibrosis, atrophy, hypothyroidism

Goitre

• What is it?

Goitre

• What is it?– Enlarged thyroid– Due to impaired thyroid hormone synthesis

Goitre

• What is it?– Enlarged thyroid– Due to impaired thyroid hormone synthesis

• Causes

Goitre

• What is it?– Enlarged thyroid– Due to impaired thyroid hormone synthesis

• Causes– Iodine deficiency– Goitrogens– Inherited disorders

Goitre

• Pathogenesis– Hyperplasia of follicular epithelium– Increased thyroid hormone release (decreased colloid)– Involution of follicles when enough thyroid hormone

released– Accumulation of colloid

• Two forms:– Diffuse– Multinodular

Goitre

• Gross findings

– Diffuse: Diffuse enlargement without nodules

– Multinodular:

Goitre• Microscopic findings

– Diffuse (initial hyperplastic stage):• Hyperplastic and hypertrophied follicles• Decreased colloid

– Diffuse (involution stage)• Dilated follicles, atrophic epithelium• Abundant colloid

Goitre• Microscopic findings

– Multinodular goitre:

– Recurrent episodes of stimulation and involution• Hyperplastic and hypertrophied follicles with decreased

colloid

• Dilated follicles with atrophic epithelium and abundant colloid

• Haemorrhage, fibrosis, calcification, cyst formation

Thyroid neoplasms

• Risk factors– M:F = 1:4– Radiation therapy– Hashimoto’s– Multinodular goitre

• Types– Follicular adenoma– Carcinoma

• Papillary• Follicular• Anaplastic• Medullary

Follicular adenoma

• Morphology:

Follicular carcinoma

• Morphology:

– Same as follicular adenoma!

BUT– Vascular / capsular invasion– Haematogenous mets

Papillary carcinoma

• Morphology:

Papillary carcinoma

• Morphology:

Causes of hyperparathyroidism

Parathyroid hyperplasia Parathyroid adenoma

Hyperadrenalism

• Presentation– Cushing’s syndrome– Conn’s syndrome

• Causes– Primary

• Hyperplasia, adenoma, carcinoma

– Secondary• Hypothalamic/pituitary disorders• Ectopic ACTH secretion• Activation of renin-angiotensin system

Causes of hyperadrenalism

hyperplasia carcinoma adenoma

Causes of hypoadrenalism

haemorrhage metastases

infection (TB)

Pancreatic islet cell tumour

+

Pituitary adenoma

+

Parathyroid hyperplasia

=

MEN I

Medullary carcinoma of thyroid +

Phaeochromocytoma +

Parathyroid hyperplasia =

MEN II