The Endocrine System Flashcards
What are the three types of endocrine disease?
Over production
Underproduction
Mass lesions
Describe what happens during negative feedback of hormones?
Stimulus - gland - hormone - blood - hormone - target cells
Which hormones are released from the posterior pituitary?
Oxytocin and ADH
Which 6 hormones are released from the anterior pituitary?
Growth hormone, lutenising hormone, follicle stimulating hormone, prolactin, adrenocortitrophic hormone, thyroid stimulating hormone.
What diseases of the pituitary can you get?
Adenomas - hyper
Injury, surgery, radiation, inflammation - hypo
Local mass effect - compression of optic chasm
What is the most common cause of hyperpituitarism?
Adenoma
What are the two types of pituitary adenomas?
Functional - secretes prolactin
Non functional - grows but no hormone
How big are macro adenomas?
> 1cm in diameter
Which five hormones can be produced by pituitary adenomas?
Prolactin, growth hormone, FSH/LH, TSH, ACTH.
What causes excess growth?
Acromelagy
When does hypopituitarism occur?
With loss of 75% or more of the anterior pituitary parenchyma.
Give four causes of hypo pituruitarism
Ischaemic necrosis of the pituitary - sheehans syndrome. (After pregnancy, bleed, hypotension.)
Non functioning adenomas
Surgery or irradiation
Inflammatory lesions
Describe the thyroid system
Hypothalamus - TRH
Anterior pituitary - TSH
Thyroid gland - T3 and T4
Negative feedback
List five causes of hyperthyroidism
Graves' disease Over treatment by thyroxine Infective - de Quervains thyroiditis Toxic multinodular goitre Toxic adenoma
How would you test for hyperthyroidism?
Thyroid function test
How would you treat hyperthyroidism?
Carbimazole/propylthiouracil with thyroxine
Radioactive iodine
Thyroidectomy
Treat the cause
What is a complication of hyper and hypothyroidism?
Goitre
Give five causes of hypothyroidism
Iodine deficiency Hashimoto's thyroiditis Latrogenic - surgery, radiation Pituitary defects Congenital
How would you manage hypothyroidism?
Thyroxine
What is the most common type of thyroid cancer?
Papillary carcinoma
What does the parathyroid hormone control?
Calcium absorption
What are three causes of hypoparathyroidism?
Thyroidectomy
Congenital
Hereditary (autoimmune)
What are symptoms of hypoparathyroidism?
Muscle contractions
Irritability
Tetany
Seizures
What are the symptoms of hyperparathyroidism?
Constipation Dizziness Seizures Depression Muscle wasting Polyuria Bone fractures Kidney stones
What are the causes of hyperparathyroidism?
Primary - adenoma
Secondary - chronic renal failure
Tertiary - after renal transplant
Describe the train of hormones secreted from the adrenal glands
Hypothalamus - CRH Anterior pituitary - ACTH Zona glomerulosa - mineralocorticoids Zona fasciculata - glucocorticoids Zona reticularis - testosterone, oestrogen
What causes hyperaldosteronism?
Primary - conn’s disease
Secondary - due to high renin
What are the symptoms of conn’s disease?
Oedema
Hypertension
High sodium
Low potassium
What are four purposes of cortisol?
Essential to life
Emulates blood sugar
Inhibits inflammation
Stress response
What is it called when you have an excess release of cortisol?
Cushing’s syndrome
When are your levels of cortisol lowest?
In the morning
What two things can cause Cushing’s syndrome?
ACTH releasing tumour - pituitary/lung
Steroids
What three things can cause Addison’s disease?
Autoimmune
Infection
Neoplasms
What are 4 symptoms of Addison’s disease?
GI - vomiting, diarrhoea, nausea, anorexia
Weight loss
Hyperpigmentation
Low sodium, high potassium
What is the name of a tumour of the adrenal medulla?
Phaeochromocytoma
What are the symptoms of a phaemochromocytoma?
Hypertension, sweating, palpitations, nervousness, increased metabolic ratio, rapid heart rate.
What is multiple endocrine neoplasia?
Group of inherited diseases resulting in proliferative lesions of multiple endocrine organs
