Thyroid Disease Flashcards
What condition does a congenital deficiency in thyroid hormone result in?
Cretinism - thyroid hormones are v. important in the growth and development of the CNS, deficiency results in this form of mental retardation.
Suggest three possible causes of hyperthyroidism.
- Grave’s disease (autoimmune)
- Drugs (amiodarone etc.)
- Malignancy (toxic adenoma)
Describe the pathophysiology of Grave’s disease.
- IgG autoantibody binds to the TSH receptor acting as an agonist
- This leads to uncontrolled generation and secretion of T3 & T4, which reduces the level of TSH via negative feedback
Suggest some common presentations of hyperthyroidism.
Symptoms:
- Heat intolerance
- Weight loss (despite increased appetite)
- Irritability
Signs:
- Exopthalmos
- Lid lag
- Tremor
- Tachycardia
- Sweating (heat intolerance)
Suggest THREE different treatments for hyperthyroidism.
- Carbimazole (which is the pro-drug of methimazole) or other thioamine
- Radioactive iodine (131 I-)
- Surgical removal of the thyroid gland
N.b. B-blockers can be used for the symptoms of hyperthyroidism, however, they are management not treatment
Describe how a thioamine such as carbimazole works to treat hypethyroidism.
- Pro-drug which is activated to methimazole
- Compete with thyroglobulin for oxidised iodide (the enzyme that does this thyroid peroxidase)
N.b. as they are affecting the synthesis, not the secretion, these drugs take a few weeks to come into effect
Suggest some possible ADRs associated with treatment of hyperthyroidism with carbimazole.
- Rashes/pruritus
- Goitre formation
- Bone marrow suppression (throat infection, fevers etc.)
- Affects on oestrogen
Suggest some possible complications of thyroid surgery.
- Damage to the recurrent laryngeal nerve
- Post-op bleeding
- Infection
- Hypoparathyroidism (need to give them some calcium)
Suggest some possible complications of hyperthyroidism.
- Atrial fibrillation (test for it)
- Angina
- Osetoporosis
- Heart failure (cardiomyopathy pathogenesis)
Suggest some possible causes of hypothyroidism.
- Autoimmune (Hashimoto’s)
- Iodine deficiency
- Surgical removal of the thyroid
- Drug induced (amiodarone can cause it, but, is more likely to cause hyperthyroid)
How may a patient with hypothyroidism present?
- Cold intolerance
- Weight gain
- Tiredness, lethargy
- Thinning hair
- Constipation
- Menorrhagia
Suggest a possible differential diagnosis for a patient who presents with symptoms/signs indicative of hypothyroidism.
- Anaemia
- Coeliac disease
- Chronic fatigue syndrome
- Diabetes
- Anxiety/depression
- Drugs
- Cushings
Suggest a possible differential diagnosis for a patient who presents with symptoms/signs indicative of hyperthyroidism.
- Malignancy
- Panic/anxiety
- Infective
- Caffeine
- IBD
Suggest THREE conditions that may be associated with hypothyroidism.
- Turner’s/Down’s
- Cystic fibrosis
- Primary biliary cirrhosis
