Thyroid Disease Flashcards
What are some causes of hypothyroidism?
- Hashimoto’s thyroiditis
- Subacute thyroiditis (hyper then hypo)
- Iodine deficiency
- Treatment for hyperthyroidism
- Medications eg, Lithium or amiodarone
- Postpartum hypothyroidism
- Secondary causes eg, hypopituitarism
Explain features of Hashimoto’s thyroiditis
- Autoimmune inflammation caused by anti-thyroid peroxidase antibodies (and anti-thyroglobullin antibodies)
- Associated with Addison’s disease, pernicious anaemia, T1DM and coeliac’s disease
Explain the presentation of Hypothyroidism
- Weight gain
- Macroglossia
- Cold intolerence
- Dry skin
- Coarse hair/ hair loss
- Fatigue
- Fluid retention
- Oedema,
- Plural effusions
- Ascites
- Amenorrhoea
- Constipation
- Decreased tendon reflexes
- Carpal tunnel syndrome
- Cerebellar ataxia
- Bradycardia
- Cardiomegaly
- Peripheral neuropathy
What are the investigations for Hypothyroidism. What are he differnet results for primary/secondary
- TSH, T3 and T4 levels
- In primary hypothyroidism there is high TSH and low T3/T4
- In secondary hypothyroidism there is low TSH and low T3/4
What is the treatment for hypothyroidism and its side effects
Levothyroxine (metabolised to T3) titrated up (measure monthly TSHs). Therapeutic goal is normalisation of TSH
Side effects: Hyperthyroidism, reduced bone mineral density, worsening of angina, atrial fibrillation
What are the causes of hyperthyroidism?
- Graves Disease (TSH autoantibodies mimic TSH)
- Toxic multinodular goitre (nodules act independantly)
- Solitaty toxic thyroid nodule (usually adenoma)
- De Quervain’s thyroiditis
What is the difference between primary and secondary hyperthyroidism
- Priamry is caused by thyroid pathology
- Secondary is caused by a pituitary or hypothalamic pathology
What are the symptoms of hyperthyroidism?
- Symptoms of hyperthyroidism
Anxiety and irritability,
Sweating and heat intolerance,
Tachycardia (AF),
Fine tremor
Weight loss,
Thyroid bruit
Fatigue,
Frequent loose stools
Sexual dysfunction - Symptoms of Graves
Diffuse goitre
Thyroid eye disease - Lid lag, lid retraction, exophthalmoses
Pretibial myxoedema
Thyroid acropachy
What is De quervain’s thyroiditis?
Viral infection which causes fever, neck pain, tenderness, dysphagia and hyperthyroidism (followed by hypothyroidism)
Self limiting (treated with NSAID and BBs for hyper symptoms)
What is thyroid storm/ thyrotoxic crisis?
- Acute severe presentationdue to excess thyroid hormone.
- Usually precipitated by surgery, trauma or infection.
Explain the presentation of thyroid storm
Presents with pyrexia, tachycardia, nausea and vomiting, confusion and delirium
Requires admission for monitoring
Explain the management of thyroid storm
- IV propranolol
- IV Digoxin
- Propylthiouracil via NG tube followed by Lugol’s iodine 6 hours later
- Prednisolone/hydrocortisone
What is the management of hyperthyroidism?
Either titration block or block and replace
Carbimazole (risk of agranulocytosis)
Propylthiouracil (small risk of severe hepatic reactions) Used in first trimester of pregnancy
Radioactive iodine (may result in hypothyroidism)
Beta blockers for symptoms (propranolol)
WHat are the test results for subclinical hyper/hypo-thyroidism?
Hyper - Low TSH and High T3/T4
Hypo - High TSH but normal T3/4
What is sick euthyroid syndrome?
Low TSH and low T4 (common in hospitals)