- Commonest is Graves disease (auto Ab to TSH receptor with XS T4 and reduced TSH from pituitary)
- Thyroid adenoma (or rarely carcinoma)
- Toxic multi-nodular goitre
- TRH producing pituitary adenoma
- Iodine or amiodarone administration.
- 1% of thyrotoxic pushed by trigger (AMI, meds change, sepsis, surgery etc.) into thyroid storm (30 - 60yo)
- Life threatening hyper-metabolic state
- Clinical Dx
- Wt loss, tachyarrhythmias, alopecia, eye abnormalities etc
- Hyper-metabolic state (pyrexia, hypertension, tachycardia [AF], tachypnoea, CCF, eye signs, hyperglycaemia)
- Low TSH, high T3 T4
- Look for precipitating cause (particularly sepsis)
- Beware CCF (arrhythmia, persistent hypertension, cardiomyopathy)
Management thyrotoxicosis / storm
- Target each T4 synthesis step
- Propylthiouracil (PTU) (inhibits hormone synthesis and T4 to T3 conversion).
- Propanolol (inhibits target organ effects and inhibits conversion T4 to T3)
- Iodine (inhibits T4 release from gland: but never unless PTU already given as may stimulate T4 release)
- Consider steroids (any signs of Addison’s?)
- Consider paracetamol for pyrexia etc.
- Avoid Aspirin (unbinds T4 from plasma proteins)
- Avoid amiodarone (self explanatory)
- ACEI or diuretics usually safe if required (CCF)
- Anticoagulation if in atrial fibrillation
Content by Dr Íomhar O' Sullivan 04/02/2011. Last review Dr ÍOS 4/12/18.