Thyroid disorders Flashcards
1
Q
Define hyperthyroidism
A
Overactivity of the thyroid gland resulting in excess thyroid hormone
2
Q
Causes of hyperthyroidism (6)
A
- Grave’s disease (most common)
- Toxic multinodular goitre
- Toxic thyroid adenoma
- Pituitary adenoma -> more TSH, high T3/T4
- De Quervain’s thyroiditis
- Drug induced
3
Q
Hyperthyroidism RF (5)
A
- Female
- Family history/genetic (HLA-DR3/4)
- Stress
- Smoking
- Amiodarone
4
Q
Pathology of Graves’ disease
A
- Serum IgG antibodies called TSH receptor stimulating antibodies (TRAb) bind to TSH receptors on thyroid and stimulate T3/4 production
- Excess secretion, follicular hyperplasia, hyperthyroidism and goitre
5
Q
Specific symptoms of Graves’ disease (4)
A
- Graves’ ophthalmology (extraocular muscle swellings - protruding eyes, lacrimation,, eye discomfort, diplopia)
- Pretibial myxoedema (raised purple/red symmetrical skin lesions over anterolateral aspect of the shins)
- Thyroid acropachy (finger clubbing, periosteal new bone formation)
- Goitre
6
Q
Symptoms of hyperthyroidism (9)
A
- Weight loss
- Heat intolerance
- Irritability
- Sweating
- Insomnia
- Diarrhoea
- Palpitations
- Anxiety
- Menstrual disturbance
7
Q
Signs of hyperthyroidism (9)
A
- Tachycardia/AF
- Tremor
- Goitre
- Hyperkinesia
- Lid lag
- Lid retraction
- Thin hair and hair loss
- Onycholysis - painless separation of the nail from nail bed
- Exophthalmos - bulging of eye
8
Q
Investigations for hyperthyroidism (4)
A
- TFTs - primary = low TSH, high T3/T4, secondary = high TSH/T3/4
- Thyroid autoantibodies - thyroglobulin antibodies, TRAb, thyroid peroxidase antibodies (more in hypo)
- Thyroid ultrasound
- Radioactive iodine isotope uptake - high in Graves’
9
Q
Treatment of hyperthyroidism (4)
A
- Beta blockers - reduces SNS activation
- Carbimazole - blocks thyroid hormone synthesis and is immunosuppressant
- Radioiodine therapy - iodine taken up and local irradiation and tissue damage
- Thyroidectomy - thyroid replacement needed
10
Q
Complications of thyroidectomy (7)
A
- Bleeding
- Post-op infection
- Hypocalcaemia
- Hypothyroidism
- Hypoparathyroidism
- Recurrent laryngeal palsy - laceration
- Recurrent hyperthyroidism
11
Q
Complications of hyperthyroidism
A
- Congestive HF
- AF
- Osteoporosis
- Graves’ ophthalmology complications
- Graves’ dermopathy - elephantitis
12
Q
Thyroid crisis/storm
A
Rapid deterioration of thyrotoxicosis with
- Hyperpyrexia
- Tachycardia
- Restlesslessness
- Delirium, coma, death
13
Q
What is thyroid crisis precipitated by?
A
- Infection
- Stress
- Surgery
- Radioactive iodine therapy
14
Q
Treatment of thyroid crisis
A
- Large dose carbimazole
- Propranolol
- Potassium iodide - acutely block thyroid hormone release from gland
- Hydrocortisone - inhibit peripheral conversion of T4 to T3
15
Q
Define hypothyroidism
A
Underactivity of the thyroid gland. Affects women more than men.
16
Q
Causes of hypothyroidism (5)
A
- Post-partum thyroiditis
- Autoimmune thyroiditis
- Iodine deficiency
- Iatrogenic
- Congenital hypothyroidism
17
Q
Drugs inducing hypothyroidism
A
- Carbimazole
- Lithium
- Amiodarone
- Interferon
18
Q
Drugs inducing hyperthyroidism
A
- Iodine
- Amiodarone
- Lithium
19
Q
Signs of hypothyroidism : BRADYCARDIC
A
Bradycardia Reflexes relax slowly Ataxia Dry thin hair/skin Yawning/drowsy/coma Cold hands (+low temp) Ascites (+non pitting oedema + pericardial/pleural effusion) Round puffy face Defeated demeanour Immobile CCF
20
Q
Symptoms of hypothyroidism (10)
A
- Weight gain
- Hoarse voice
- Goitre
- Cold intolerance
- Menorrhagia
- Constipation
- Lethargy/tiredness
- Poor memory
- Puffy eyes
- Arthralgia/myalgia
21
Q
Diagnosis of hypothyroidism
A
- High TSH, low T4
- Low TSH and T4 - rare pituitary fault
- High cholesterol and triglyceride, macrocytosis
- Normochromic anaemia (less common)
22
Q
Causes of primary hypothyroidism
A
- Primary atrophic hypothyroidism - lymphatic infiltration, atrophy, no goitre
- Hashimoto’s thyroiditis - lymphocytic and plasma cell infiltration, goitre, more common in women 60-70
- Iodine deficiency
- Thyroidectomy or radioiodine treatment
- Drug-induced
- Subacute thyroiditis
23
Q
Treatment of hypothyroidism
A
- Healthy and young - levothyroxine 0-100mcg/24h, review 12wks
- Elderly or ischaemic heart disease - 25mcg/24h
Aim to get TSH >0.5
24
Q
Types of thyroid cancer (good-> bad prognosis)
A
- Papillary
- Follicular
- Medullary cell
- Lymphoma
- Anaplastic
25
Symptoms of thyroid cancer
1. Thyroid nodules
2. Dysphagia
3. Hoarseness of voice
26
Signs of thyroid cancer
1. Lymph node metastases
2. Bone or lung metastases (rare)
3. Thyroid nodule with history of progressive increase in size
4. Hard and irregular nodule
5. Enlarged lymph nodes
27
Investigations for thyroid cancer
1. Fine needle aspiration cytology biopsy
2. Thyroid ultrasound
3. TFTs - hyper/hypothyroidism must be treated before surgery
28
Treatment for thyroid cancer
1. Papillary and follicular - total thyroidectomy with neck dissection, ablative radioiodine
2. Anaplastic and lymphoma - external radiotherapy, mainly palliative
