Graves Disease Flashcards
what is the clinical presentation of Graves disease?
- anxiety
- unintentional weight loss (over short period of time)
- hyperphagia (increased appetite)
- resting tremor
- increased blowel frequency
- initial insomnia
- heat intolerance
- diaphoresis (excessive sweating)
- amenorhea in women
- pretibial myxoedema
- lump over thyroid gland
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what should you look for in the family history when considering a graves disease diagnosis?
a family history of autoimmune disorders ie) underactive thyroid/overactive thyroid, psoriasis, Type 1 diabetes etc .
What are some examination findings for a patient with hyperthyroidism?
gen inspection:
- anxiety
- irritability
- restlessness
- fatigue
- weight loss despite normal or increased appetite
- perspiration/heat intolerance
Specific inspection
- hands: tremor, palmar erythema, perspiration and potentially clubbing
- eyes: exophthalmos, lid lag, opthalmoplegia due to optic nerve damage
- neck: enlarged thyroid swelling, potential goitre
- chest: gynecomastia in men
- legs: pretibial myxoedema
what would you find upon palpation in a patient with Graves disease?
- skin: perspiration, increased temp, pretibial thickening
- neck: firm swelling that may be tendor or non-tender
- abdomen: possible splenomegally due to lymph node hyperplasia
what would you hear upon auscultation in a patient with graves disease?
bruit over swelling in neck due to increased blood flow- may also hear stridor if there is compression of the trachea
what bedside exams can we perform in a patient with signs of graves disease?
Blood pressure - check for hypertension
ECG - check for tachycardia or atrial fibrillation
reflexes- hyperreflexia
what is the major indicator in the eyes of Graves disease?
Exophthalmos
what is the differential diagnosis for thyrotoxicosis?
- Graves Disease - body produces autoantibodies for TSH receptors on the thyroid which stimulates formation of excess T3 and T4 leading to thyrotoxicosis
- Toxic Multinodular Goitre- same signs/symptoms of graves, but usually presents in older patients and a present goire will likely be asymmetrical
- Solitary adenoma - same signs/symptoms of graves disease but usually presents in older patiens with a nodular thyroid goitre
- Thyroiditis - viral infeciton results in inflammation and release of T3 and T4 - would prsent with fever
What laboratory tests should be ordered to confirm Graves Disease and rule out other DDs?
- thyroid function test - test for primary hyperthyroidism (suppressed TSH but raised T3/T4) or secondary hyperthyroidism (raised T3/T4 and raised TSH)
- auto-antibody test - test for antibodies for TSH receptors
- FBC - test for active immune response in body
- U&E= hormone disorders often effect electrolytes- need to correct
- LFT- test for potential hepatotoxicity
- inflammatory markers - rule out thyroiditis
- pregnancy test - important for treatment options
what sort of managment strategies do we have for patients with hyperthyroidism?
First line treatment = beta blokers - treat anxiety/heart palpitations, antithyroid medication (two potential methods, block and replace or dose titration) - dose titration is done more often - using carbimazole or PTU (Carbimazole not used during pregnancy)
why is surgical intervention rarely used for graves disease?
b/c of the great blood supply of the thyroid- risk of haemorrhage
nerve supply - could lead to vocal cord damage
- removal of thyroid gland leads to hypothyroidism
Describe the normal synthessis of T3 and T4?
Thyroid gland controlled by the hypothalamic-pituitary- thyroid axis - TRH is released from hypothalamus
- TRH stimulates release of TSH from the Anterior pituitary gland
- TSH binds to TSH receptors on thyroid to stimulate production of T4 and T3
- T3 and T4 feedback to inhibit the further secretion of TSH and TRH
which is more potent? T3 or T4?
T3 is 4-5 fold higher potency than T4,= this is due to a higher affinity for its nuclear receptor
what is graves disease?
an autoimmune condition where antibodies are produced against the Thyroid Stimulating Hormone Receptor (TSHR) on the thyroid gland.
What is a goitre? Why does it move when you swallow?
goitre= swelling of the neck caused by an increase in thyroid gland size
the goitre moves when swallowing b/c it is attached to the larynx which elevates during swallowing
