Thyroid Disorders Flashcards
What is thyrotoxicosis?
Effect of abnormal thyroid hormone quality
What is primary hyperthyroidism due to?
Thyroid pathology
What is secondary hyperthyroidism due to?
Hypothalamus/pituitary physiology (TSH related)
What is subclinical hyperthyroidism characterised by?
Normal T3 and T4
Low TSH
What is subclinical hypothyroidism characterised by?
Normal T3 and T4
High TSH
What are the causes of hyperthyroidism?
GIST
-Graves disease
-Inflammation
-Solitary toxic thyroid nodule
-Toxic multinodular goitre
How does hyperthyroidism present?
Anxiety and irritability
Sweating and heat intolerance
Tachycardia
Weight loss
Fatigue
Insomnia
Loose stools
Brisk reflexes
fever + tachycardia + delirium = thyroid storm
(Exacerbation of each thyroid symptom)
How is hyperthyroidism investigated?
Thyroid function tests
Scintigraphy
USS
Mainly thyroid function tests lol
What is the main treatment for hyperthyroidism?
What is the common side effect?
TPO inhibiting drugs-
Carbimazole once a day
Never give in first trimester of pregnancy
Or
Propylthiouracil twice a day
Never give in 2nd or 3rd trimester of pregnancy
May cause agranulocytosis-> common pres = persistent sore throat
What are the other options to treat hyperthyroidism?
Iodine radiotherapy-> iodine drank, taken up by thyroid and proportion is killed
Long term levothyroxine after 6 month remission
Contraindicated in pregnancy, and fathering children within 4 months of dose
propanolol- blocks adrenaline related symptoms
thyroidectomy- life long levothyroxine required
What are the specific features of Graves’ disease?
Diffuse goitre
Graves eye disease (exophthalamos)
Pretibial myxoedema (rash on lower legs)
Acropachy- hand swelling and finger clubbing
What causes thyroiditis?
De Quervains thyroiditis
Postpartum
Drugs
Radiation
Bacteria
De quervains thyroiditis
Viral trigger -> neck pain and tender goitre, dysphagia, hyperthyroid symptoms
Age 20-50
Investigated by scintigraphy
Self limiting but can give beta blockers and NSAIDs for pain and sometimes steroids
Starts hyper, turns to hypo
What drugs can induce thyroiditis?
Amiodarone
Lithium
May present with blue/grey skin discolouration
What can hypothyroidism be classified into?
Congenital- born with under active thyroid
Accquired- develops underactive thyroid
What causes congenital hypothyroidism?
How is it tested?
How does it present in newborns?
Dysgenesis- underdeveloped
Dyshorogenesis- doesn’t produce enough hormone
Pituitary issues
Newborn blood screening
Prolonged neonatal jaundice
Poor feeding and slow growth
Constipation
Increased sleeping and reduced activity
What causes acquired hypothyroidism?
How is it tested?
How is it treated?
Most common cause is hashimoto thyroiditis
Tested with anti TPO antibody and thyroid function tests
Treated with levothyroxine once daily
What is hashimoto thyroiditis?
What is the associated antibody?
What are the associated conditions?
Autoimmune thyroid gland inflammation- most common cause of hypothyroidism
Anti TPO
T1DM, coeliac
How does hypothyroidism present?
Fatigue and low energy
Weight gain
Poor school performance
Constipation
Dry skin and hair loss
Queen Anne’s sign- loss of outer third of eyebrow
How is hypothyroidism treated?
Levothyroxine once daily, lower dose in older patients or those with cardiac disease
Primary hyperthyroidism- Thyroid function test results
Low TSH, High T3 T4
Secondary hyperthyroidism- Thyroid function test results
High TSH, T3 and T4
Subclinical hyperthyroidism- Thyroid function test results
Low TSH, normal T3 and T4
Primary hypothyroidism- Thyroid function test results
High TSH, low T3 and T4
Secondary hypothyroidism- Thyroid function test results
Low TSH, low T3 and T4
Subclinical hypothyroidism- Thyroid function test results
High TSH, normal T3 and T4
What is the most common cause of hypothyroidism in the Middle East?
Iodine deficiency
What antibody is associated with Graves?
TSH- receptor stimulating
