Session 10: Thyroid Disorders Flashcards
Different ways to examine thyroid and investigate.
(Not blood tests)
Palpate it. If the size of the thyroid is normal you will not be able to feel it.
Thyroid ultrasound
Radio-isotope scan (Scintography) with technetium-99m
What is lingual thyroid?
Since the embryological origin of the thyroid is in the foramen cecum in the tongue (middle of the tongue).
If embryology fails you might end up with a lingual thyroid which is a sort of ectopic thyroid gland.
Treatment of hypothyroidism.
Usually levothyroxine (T4) for life
The starting does depends on levels of T3, T4 and the symptoms severity.
Side-effects of levothyroxine treatment.
You might induce hyperthyroidism.
Also in elderly patients and patients with heart disease the levothyroxine can be harmful in large doses due to its sympathomimetic effects. This can cause tachycardia and increased inotropy.
What is myxoedema coma?
Severy hypothyroidism which usually occur in the elderly if it occurs at all as it is really rare.
This can lead to hypothermia and fluid overload in heart causing pericardial effusion.
The mortality of myxoedema coma is 50% so requires high dependency treatment.
Symptoms of hyperthyroidism.
Weight loss
Irritability
Restlessness
Insomnia
Malaise
Icthing
Sweating
Palpitations
Tremor
Muscle ache
Diarrhoea
Signs of hyperthyroidism
Tremor
Hyperkinesis
Tachycardia
Atrial fibrillation
Warm peripheries
Hypertension
Proximal myopathy
Lid lag
Lid retraction
Explain lid lag and lid retraction
Due to the sympathomimetic effects of T3 and T4 lid lag and lid retraction occurs.
This is because there is a sympathetic branch of levator palpebrae superioris in the eye which under sympathetic influence will pull the eye lid upwards.
Specific signs of Grave’s disease.
Grave’s opthalmopathy
Pretibial myxoedema also called Grave’s dermopathy
Briefly explain thyroiditis.
Give causes.
Inflammation of thyroid causing release of thyroxine into circulation.
This can be caused by viral infection
After childbirth
Medication like amiodarone
How does acute and chronic thyroiditis differ?
Acute can manifest signs of hyperthyroidism even though it is not an overactive thyroid. Better word is thyrotoxicosis.
Chronic will manifest signs of hypothyroidism. And it is also hypothyroidism.
Treatment of hyperthyroidism.
Medication:
Carbimazole or propylthiouracil to treat the thyroid issue.
Betablockers to treat the symptoms (tachycardia and heart palpitations)
Surgery:
Removal of thyroid gland
Misc:
Radioactive iodine
Side effects of Carbimazole.
Rare side effect but it can cause agranulocytosis -> neutropenia.
So risk of infection and patient might get rashes and fever.
Complications of surgery.
Cosmetics although usually minor
Small risk of laryngeal nerve palsy and hypocalcaemia if there is damage to parathyroid glands.
What is thyroid storm/thyroid crisis?
A rare condition with 10% mortality where the patient becomes hyperpyrexic, tachycardic, cardiac failure and liver dysfunction.
This needs urgent treatment of beta blockers and carbimazole
What is neonatal Grave’s disease?
If a mother has Grave’s disease she can give of antibodies (the TSI) to the child in utero. This can cause the child to have hyperthyroidism when they are born. However it goes into remission as the mother’s antibodies disappear.
They are treated as an infant though.
Types of goitre.
Diffuse goitre:
Simple goitre
Auto-immune thyroid disease like Hashimoto’s and Grave’s
Thyroiditis
Nodular goitre:
Multinodular goitre which is the most common in the UK Solitary nodule (*_Red flag for cancer_*)
Fibrotic goitre:
Riedel’s thyroiditis which is rare
Iodine deficiency:
Common worldwide but rare in the UK
Red flag symptoms of thyroid cancer
Very young or old patient
Rapid enlargement of lump in neck
Hoarse voice and dysphagia
Family history of thyroid cancer
Hard irregular thyroid mass
Fixed to surrounding structures meaning it won’t move on swallowing
Cervical lymph nodes
Investigation of suspected thyroid cancer
Thyroid ultra-sound
CT scan thorax and mediastinum
Fine needle aspiration
Thyroid scintology
