Endocrinology

Question 1

What are hormones?

Answer 1

Molecules secreted into the blood with regulatory actions at distant sites

Question 2

How do hormones act via?

Answer 2

Receptors

Question 3

How are hormones regulated?

Answer 3

Feedback loops

Question 4

List 5 endocrine glands?

Answer 4

Pituitary gland
Thyroid and parathyroid glands
Adrenal glands
Pancreas
Ovaries/testes

Question 5

Describe the actions leading to the secretion of cortisol

Answer 5

Corticotrophin releasing hormone released from the hypothalamus
This stimulates Adrenocorticotrophic hormone to be released from pituitary gland
This travels in the blood stream to the adrenal cortex which secretes cortisol
When cortisol levels are high this causes negative feedback loop to hypothalamus and CRH stops being made

Question 6

How is thyroxine produced?

Answer 6

Thyroid-releasing hormone secreted from hypothalamus causes release of thyroid stimulating hormone from pituitary gland
This causes release of thyroxine from thyroid

Question 7

What hormone does the adrenal medulla secrete?

Answer 7

Adrenaline

Question 8

What hormone does the parathyroid secrete?

Answer 8

Parathyroid hormone - effects plasma calcium

Question 9

What does the adrenal cortex release when not governed by the pituitary gland)?

Answer 9

Aldosterone - effects plasma volume

Question 10

What do the pancreatic islet of langerhans secrete?

Answer 10

Insuline, glucagon

Question 11

List 5 mechanism of endocrine disease?

Answer 11

Autoimmune destruction of gland
Autoimmune stimulation of gland
Destruction of gland - surgery, cancer
Tumour formation
Effects of tumour - hypersecretion

Question 12

What is the effect of Cushing’s syndrome?

Answer 12

Hypercortisolism - too much cortisol from adrenal cortex

Question 13

What causes hypercortisolism?

Answer 13

Excess exogenous steroids

Damage to the hypothalamus pituitary axis e.g. ACTH secreting pituitary tumour or Cortisol secreting adrenal tumour

Question 14

Adrenal clinical features of Cushing’s syndrome?

Answer 14

Moon face - increase adipose tissue
Buffalo hump
Abdominal obesity
Proximal muscle weakness
Thin skin
Bruising

Question 15

How is Cushing’s syndrome investigated?

Answer 15

Test cortisol level in urine

Measure ACTH to decide where the abnormality is

Question 16

How is Cushing’s syndrome treated?

Answer 16

Surgery - adrenalectomy

Question 17

What is Addisons disease?

Answer 17

Hypo-adrenalism (hypocortisolism) - due to destruction of adrenal cortex

Question 18

Causes of hypo-adrenalism?

Answer 18

Destruction of adrenal cortex - Addison’s disease
Suppression of hypothalamus-pituitary-adrenal axis following steroid treatment
Adrenal tumour
Pituitary failure - lack of ACTH

Question 19

Clinical features of hypoadrenalism

Answer 19

Tiredness
Weight-loss
Pigmentation of skin
Hypotension
Hypoglycaemia

Question 20

Features of Addisonian crisis?

Answer 20

Vomiting
Dehydration
Hypotension
Hypoglyaemia

Question 21

How is hypoadrenalsim investigated?

Answer 21

Low cortisol levels
High ACTH
Adrenal antibodies

Question 22

How is hypoadrenalism treated?

Answer 22

Replacement of cortisol - hydrocortisone

Question 23

What is hyperthyroidism?

Answer 23

Excess thyroxine and tri-iodothyronine from thyroid

Question 24

Causes of hyperthyroidism?

Answer 24

Graves disease

Thyroid adenoma

Question 25

Features of hyperthyroidism?

Answer 25

``` Sped up metabolism - too much adrenaline (stimulated when thyroid levels high) - hot - weightloss - increased appetite - poor sleep - loose bowels graves disease ```

Question 26

Diagnosis of hyper-thyroidism?

Answer 26

Raised thyroxine and tri-iodothyronine Suppressed TSH Thyroid stimulating antibodies

Question 27

Treatment of hyper-thyroidsim?

Answer 27

Surgical thyroidectomy Anti-thyroid drugs Beta-blockers

Question 28

What is hypothyroidism?

Answer 28

Lack T4 and T3 - high TSH

Question 29

Causes of hypothyroidism?

Answer 29

Autoimmune destruction of thyroid Surgical removal of thyroid Secondary to TSH lack in pituitary disease

Question 30

Features of hypothyroidism?

Answer 30

Slow metabolism - cold - dry skin - slow, tired - weight gain - poor appetite

Question 31

What is acromegaly?

Answer 31

Excess growth hormone from pituitary gland

Question 32

What causes acromegaly?

Answer 32

Pituitary tumour

Question 33

Diagnosis of acromegaly?

Answer 33

High GH, doesn't suppress with glucose (negative feedback)

Question 34

Features of acromegaly?

Answer 34

``` Enlarged hands. feet. jaw, skull Coarse facial features Thick skin Arthritis (TMJ) Hypertension Hyperglycaemia ```

Question 35

What is hyperparathyroidism?

Answer 35

Increased calcium production

Question 36

Caused by hyperparathyroidism?

Answer 36

Tumour, Vit D excess, cancers

Question 37

Features of hyperparathyroidism?

Answer 37

Dry eyes and mouth Thirst, polyuria Loss of lamina dura Reduced cortical width of mandible and ground glass appearance

Question 38

Effect of hypoparathyroidism?

Answer 38

Hypocalcaemia

Question 39

Causes of hypoparathyroidism?

Answer 39

Autoimmune destruction | Damage to parathyroids

Question 40

Features of hypocalacemia?

Answer 40

Tingling, paraethesiae | Cramps