L3 Nuts and Bolts CC

Question 1

Clinical Manifestations of endocrine diseases?

Answer 1

• Hormone overproduction
• Hormone underproduction
• Tumour/mass lesion which can be:
  1. Non-functional → pressure effect
  2. Associated over production of hormones

Question 2

Histology of the anterior pituitary gland

Answer 2

Acidophils- secrete growth hormone, prolactin
Chromophobe- ACTH, TSH, FSH, LH
Basophils

Question 3

What cells secrete ACTH?

Answer 3

Secreted from both chromophobes and basophils

Question 4

Productive adenomas cause hyperpituitarism. What is this?

Answer 4

producing hormones

Question 5

Pituitary adenomas

‘Pressure effect causing hypopituitarism’
What does this mean?

Answer 5

not producing hormones

Question 6

Presentation of Pituitary Adenoma

Answer 6

bitemporal hemianopsia due to compression of optic chiasma

Question 7

Role of Thyroxine (T4) and Triiodothyronine (T3)

Answer 7

stimulates metabolic rate

Question 8

What is required for the synthesis of T3 and T4?

Answer 8

Iodine

Question 9

Features of the Thyroid Gland

Answer 9

-Very vascular

-The endothelial cells lining the capillaries are fenestrated (i.e. have gaps between them)
→a common feature in endocrine glands

• Fenestration allows passage of hormones into the circulation
• Para-follicular cells or clear cells (C cells) are found between the follicles
• C cells secrete calcitonin which promotes reduction of calcium concentration in the blood

Question 10

Grave’s disease

Answer 10

• Auto-antibodies stimulate TSH receptors

- Diffuse enlargement of the thyroid gland – goitre due to hyperplasia of thyroid cells

Question 11

Hashimoto Thyroiditis

Answer 11

An autoimmune disease – immune system destroys its own thyroid tissue
-Progressive depletion of thyroid cells by inflammation replaced by fibrosis
↓T3/T4↑TSH

Question 12

Hashimoto Thyroiditis

• gross appearance
• histological appearance

Answer 12

• The gland is irregular with a solid cut surface

- On histology there is a prominent lymphocytic infiltrate

Question 13

Para-follicular Cells

-location

Answer 13

a.k.a.

C cells

between follicles

C cells secrete calcitonin which promotes reduction of calcium concentration in the blood

Question 14

What are C cells?

Answer 14

origin of medullary carcinoma of the thyroid

Question 15

Phaechromocytoma

Answer 15

Tumour/neoplasm of the adrenal medulla
originate from chromaffin cells
secrete excess catcholamines
10% malignant/10% familial/10% extra-adrenal/10% bilateral

Question 16

What does ADH do?

Answer 16

facilitates the absorption of water in kidneys which concentrates the urine

Question 17

What does oxytocin do?

Answer 17

Oxytocin promotes contractions of the smooth muscle in the uterus during childbirth and myoepithelial cells in the breast during breast feeding

Question 18

Features of the Thyroid Gland

Answer 18

• 35-45g
• 2 lobes and isthmus
• Thyroid tissue is composed of follicles with variable-sized lumina
• Follicles contain colloid with eosinophilic or pink appearance
• Follicles are lined with cuboidal cells

Question 19

Implications for thyroidectomy if patient has multi-nodular goite

Answer 19

The trachea may be compressed by the multi-nodular goitre

This can cause tracheomalacia (ie softening of the trachea) causing its collapse and obstruction of the airway

Question 20

Triad of signs/symptoms in Graves Disease

Answer 20

• autoimmune thyrotoxicosis
• thyroid eye disease
• pre-tibial myxoedema

Question 21

Histopathology of thyroid gland in Graves Disease

Answer 21

The colloid has a soap-bubble appearance due to hyperactivity

Question 22

Histopathology of thyroid gland in Hashimotos Thyroiditis

Answer 22

prominent lymphocytic infiltrate/inflammation

Question 23

Parathyroid Glands

Answer 23

Secrete parathyroid hormone (PTH)
Controls the levels of calcium in the blood
Decrease in blood calcium stimulates PTH secretion

Question 24

What embryological layer is the adrenal cortex derived from?

Answer 24

mesoderm

Question 25

In embryology, where is the adrenal medulla derived from?

Answer 25

neural crest

Question 26

Diseases due to Adrenocortical hyperactivity

Answer 26

• Cushings- excess cortisol
• Conns Syndrome- excess aldosterone
• Adrenogenital syndrome- excess androgens

Question 27

Diseases due to Adrenocortical insufficiency

Answer 27

Addisons

Question 28

C cells

Answer 28

origin of medullary carcinoma of thyroid

Question 29

Origin of adrenal cortex

Answer 29

mesoderm

Question 30

Origin of adrenal medulla

Answer 30

neural crest