Thyroid disease Flashcards
(27 cards)
What is a goitre?
An enlargement of the thyroid gland
What does a goitre tell you about the thyroid levels of the patient?
Patients with a goitre may be hyperthyroid, euthyroid or hypothyroid
How do you examine the thyroid?
- Low down in neck
- Feel for thyroid cartilage (‘Adam’s apple’) then down & laterally
- Moves on swallowing
- Listen for a bruit
- Retrosternal extension - Can you get below it?
- Percuss over sternum
- Check cervical LNS
What can a retrosternal goitre lead to?
Tracheal deviation
What are the normal ranges for TSH, FT4 and FT3?
TSH 0.3 – 4.2 mu/l
FT4 12 – 22 pmol/l
FT3 3.1 – 6.8 pmol/l
What are some thyroid autoantibodies?
Anti-TPO AB - Thyroid peroxidase auto-antibody
TRAB - TSH receptor autoantibody
What is the best biomarker of thyroid status?
TSH level
What are some of the symptoms of hypothyroidism?
May be none Lethargy Mild weight gain Cold intolerance Constipation Facial puffiness Dry skin Hair loss Hoarseness Heavy menstrual periods
What are the signs of severe hypothyroidism?
Change in appearance eg face puffy and pale
Periorbital oedema Dry flaking skin Diffuse hair loss Bradycardia Signs of median nerve compression (carpal tunnel)
Effusions, eg ascites, pericardial
Delayed relaxation of reflexes
Croaky voice
Goitre
Rarely stupor or coma
What are some causes of primary hypothyroidism?
- Autoimmune hypothyroidism
- Hypothyroidism after treatment for hyperthyroidism (iatrogenic)
- Thyroiditis (temporary cause)
- Drugs (e.g. lithium, amiodarone)
- Congenital hypothyroidism (if the thyroid hasn’t developed fully)
- Profound iodine deficiency
What are some causes of secondary hypothyroidism?
Diseases of the hypothalamus or pituitary
What are the TSH, T4 and T3 levels like in primary hypothyroidism?
Increased TSH
Decreased T4 and T3
wHY????
What are the TSH, T4 and T3 levels like in secondary hypothyroidism?
Decreased TSH, T4 and T3
How would you confirm a diagnosis of primary hypothyroidism? What further investigations could you do?
Blood test (TSH, FT4 etc) to confirm diagnosis
Could also check thyroid autoantibodies, no imaging necessary
Treatment of primary hypothyroidism
Start with thyroxine 100 micrograms daily (unless elderly or ischaemic heart disease and then start 25micrograms daily with increments 4-6 weekly)
Aim for normal FT4 without TSH suppression
What is thyrotoxicosis?
Hyperthyroidism
Symptoms of thyrotoxicosis?
Weight loss Lack of energy Heat intolerance Anxiety/irritability Increased sweating Increased appetite Thirst Palpitations Pruritus Weight gain Loose bowels Oligomenorrhoea
Signs of thyrotoxicosis?
Tremor Warm, moist skin Tachycardia Brisk reflexes Eye signs Thyroid bruit Muscle weakness Atrial fibrillation
Explain the features and associations of thyroid eye disease
- Associated with autoimmune hyperthyroidism (Graves disease) in roughly 20 percent of patients
- Increased risk in smokers
- Autoantibody mediated
- Inflammation of all orbital tissues except the eye (fat, muscles, conjunctiva, eyelids)
- CT scan imaging helpful
Symptoms of thyroid eye disease?
MILD SYMPTOMS:
- Itchy/dry eyes
- Prominent eyes/change in appearance
WORRISOME SYMPTOMS:
- Diplopia/ loss of sight
- Loss of colour vision (grey/blurred patches)
- Redness/ inflammation of conjunctiva
- Unable to close eyes fully
- Ache/ pain/ tightness in or behind eye
What is proptosis?
Eyes pushed forward
What are the signs of thyrotoxicosis?
Hands - fine tremor, warm
Pulse - sinus tachycardia, AF
Neck - goitre, move when swallow, bruit/not
Eyes - lid retraction/lid lag, proptosis, exophthalmos, ophthalmoplegia, inflammation (conjunctiva)
What is autoimmune hyperthyroidism?
Graves disease - autoantibody stimulates the TSH receptor, causing excess thyroid hormone production and thyroid growth (goitre)
What are some other causes of thyrotoxicosis?
Toxic multinodular goitre
Toxic adenoma
Thyroiditis
Drugs (e.g. amiodarone)
