hyperthyroidism Flashcards
what is a type of hyperthyroidism
graves disease
what is thyrotoxicosis
Thyrotoxicosis refers to the symptoms caused by the excessive circulation of thyroid hormones. It is typically caused by thyroid gland hyperactivity
symptoms of thryotoxicis
fatigue, anxiety, heat intolerance, increased perspiration, palpitations, and significant weight loss despite increased appetite
management of thryotoxicis
initial control of symptoms with beta blockers and antithyroid drugs, often followed by definitive therapy with either radioactive iodine ablation (RAIA) of the thyroid gland or surgery.
what is an acute exacerbation of throtoxicosis called
life-threatening hypermetabolic state known as thyroid storm
what do patients with thyroid storm require
Patients with thyroid storm require urgent stabilization in critical care settings with fluids, beta blockers, antithyroid medications (propylthiouracil, potassium iodide, and parenteral glucocorticoids)
what is hyperthyroidsm
a condition characterized by the overproduction of thyroid hormones by the thyroid gland; can cause thyrotoxicosis
what is graves disease
Acute to chronic hyperthyroidism
what is the pathophysiology of hyperthyroidism
excess production of T3/T4 → compensatory decrease of TSH
Thyrotropic adenoma → ↑ TSH levels → ↑ T3/T4 levels
symptoms of hyperthyroidism
weight loss, tachycardia. goiter
how is thyroid function tested
Thyroid-stimulating hormone (TSH) level (initial screening test): Typically low/undetectable; a normal TSH level usually rules out hyperthyroidism.
Free T4 (FT4) and total T3 levels: Typically both elevated; indicated when thyrotoxicosis is strongly suspected or TSH is abnormal
can raia cause a worsening of hyperthyroidism
yes
what drug causes hyperthyroidism
amiadarone
what does raia do
destroys hyroid gland
what is the first line of antithyroid
carbimazole
what is an alternative to carbimazole
Propylthiouracil
which first line antithyroid had a slower moa
carbimazole
what is the moa of carbimazole
preventing production of t4
what is the moa of proplythiorucial
Prevents the production of T4 as well as preventing the conversion of T4 to T3
inside the cel
how often should tfts be carried out
every 6 weeks then once every 3 months
what monitoring needs to be done for propylthioracil
LFT as it can affects liver function tests
what is the aim of hyperthyroidism?
aim of hyperthyroid treatment is to get the patient in a euthyroid state(normal thyroid)
what is the titration dose regime for hyperthyroidism?
15-40mg OD until Euthyroid state is achieved then reduce to 5-15mg OD, dose
reduced gradually every 4 to 6 weeks. and therapy duration is normally for 12 to 18 months
what is the risk of overtreatment with titration regime/
Overtreatment which can lead to hypothyroid state
what is block replacement regime?
Give enough carbimazole to prevent thyroid hormone synthesis by the thyroid gland.
Levothyroxine is also given to get TFT values back to normal.
what is the disadvanatges of block regime
large number of tablets the patient needs to take
more side effects because of high dose
what are the adrs for anti thyroid drugs
agranulocytosis
hepatoxicity
acute pancreatitis
symptoms of agranulocytosis
Fever
- Sore throat mouth ulcers
- Non-specific issues like bruising etc
can pregnant women use radioactive iodine
cant be used if youre pregnant
what is thyrotoxicosis
excess circulating thyroid hormones, irrespective of the source. (Thyrotoxicosis includes hyperthyroidism but thyrotoxicosis is not always caused by hyperthyroidism)
what are the two types of
Amiodarone Induced Thyrotoxicosis (AIT)
type 1 and type 2
what is type 1 Amiodarone Induced Thyrotoxicosis (AIT)
due to excess of iodine present accelerate synthesis of new thyroid hormones secondary to the iodine load (75 mg/day, 10% iodide is released in plasma causing a 40 time increase iodine plasma concentration).
occurs usually with people with underlying thyroid diseases
what is type 2
Amiodarone Induced Thyrotoxicosis (AIT)
excess release of preformed T4 and T3 into the circulation(In type 2 AIT, destructive thyroiditis that results in excess release of preformed T4 and T3 into the circulation(11). It typically occurs in patients without underlying thyroid disease,
how is type 1 Amiodarone Induced Thyrotoxicosis (AIT) treated
Thioamides (Propylthiouracil and Carbimazole /methimazole; PTU or CZ); possibly potassium perchlorate (to inhibit iodine uptake); lithium to reduce thyroid hormone synsthesis/release
how is type 2 Amiodarone Induced Thyrotoxicosis (AIT)
glucocorticoids for anti-inflammatory and membrane-stabilizing effects (thioamides generally not recommended)
how is graves disease viewed
Radioactive iodine solution.
Will show an excess amount of iodine taken up by the thyroid gland.
