Endocrine 2 medicine Flashcards
endocrine glands
ductless glanads
release directly into the blodostream
hormones
chemical signals produced by an endocrine glands that act some distance from the gland
what does the thyroid glands pridce
thyroxine t4
tri-iodotyronine T3
(T4 usually converted to T3 which is the main hormone which has an effect on tissues)
calcitonin
what does calcitonin do
regulate blood calcium levels
cascade of hormone release from thryodi
hypothalamus secretes TRH
TSH secreted by pituitary
thyroid secretes T3/4
measurement of the thyroid hormones
T4
T3
TSH (stimulating hormone)
hypothyroidism
T4/3 insufficient
suspected if TSH higher the normal
primary hypothyroidism and secondary
1) primary hypothyroidism
- Thyroid not producing enough T4/T3
- pituitary produces more TSH to compensate
can see a goitire
2) secondary hypothyroidism
- Pituitary not producing enough TSH
- therefore lack of T3/T4
symptoms and signs of hypothyroidism
symptoms weight gain lethargy cold intolerance menorrhagia
signs - facial puffiness bradycardia hoarsness periorbital oedema
causes of primary/secondayr/teritiary hypothyroidism
primary - dyshormogenesis iodine deficiency autoimmunity post radioactivity iodine
secondya
pituitary tumour/granuloma
Tertiary
isolated TRH deficiency
indicatons for screening hypothyroidism
1) Congenital hypothyroidism
2) Treatment of hyperthyroidism
3) Neck Irradiation
4) Pituitary Surgery or Irradiation
5) Patients on lithium and amiodarone
treament of hypothyroidism
levothyroxine
graves diseas
increase T3/4
decreased TSH
goitre
abnormal thyroid stimulating IgG
causes of hyperthyroidism
autoimmune thyroid disease eg graves
nodular goitre
toxic adenoma
symtoms and signs of hyperthyroidisim
symptoms
weight loss
heat intolerance
increased sweating, appetite
signs goitre tremor tachyarida warm skin
graves disease clinical features
diffuse goitre eye signs (bulging, dry eyes)
hyperthyroidism
treatment of hyperthyroidism
oral antithyroid drugs
surgical
primary diagnostic tool for thyroid issues
FNA
hypothalamus
produces hormones which influences the pituitary to release hormones
pituitary dysfunction can lead to 3 options..
1) tumour mass effects
- can cause headaches and visual defects
2) hormone excess
- signs of excess hormone
3) hormone deficiency
- peripherally in the body
causes of hypopituitarism
pituitary tumours radiotherapy trama infarction infiltration
acromegaly and features
excess growth hormone therefore high IGF 1
Clinical features Head related - Coarse facial features - Enlargement of supraorbital ridges - Separation of teeth - Prognathism - Macroglossia
adrenal gland cortisol - how is it stimulated for production
hypothalamus produces CRH
drives production of ACTH from pituitary
cortisol released from adrenal gland
- disruption to this can be a disorder e.g. cushings
Cushing syndrome and cuases
excess glucocorticods
causes
pituitary/adrenal tumour
pituitary tumour/adrenal tumour causes
Pituitary tumour – ACTH dependant hypocortisolism (cushings)
- producing too much ACTH
- stimulates adrenal to produce too much cortisol
Adrenal tumour – ACTH independent hypocortisolism
- excess cortisol
- ACTH levels will go low
adrenal insufficiente
primary - lack of cortisol in adrenal gland, moree ACTH to compensat
Secondary , lack of cortisol production, lack of ACTH can indicate problem from pituitary
causes of adrenal insufficiency
autoimmune
tuberulosis
secondary
after treatment of cushings
after exogenous glucocorticoids
glucocorticoid cover for dental procedure
patients may be on glucocorticoids, steroids
for procedures should up the dose to prevent adrenal crisis
Simple
- double dose 1 hr before surgery, double dose for 24hrs after
major
hydrocortisone 100mg im at induction; 50mg im 6 hourly until well and then double dose oral steroids for 24 – 48hours
