Clinical thyroid disease - First half Flashcards
What are the main thyroid disorders?
Hypothyroidism
Hyperthyroidism
Goitre
Thyroid cancer
Identify the labels on the diagram below
What are the symptoms of hypothyroidism?
Hypothyroidism:
- Weight gain
- Lethargy
- Feeling cold
- Constipation
- Dry skin/hair, hair loss
- Heavy periods
What are the signs of hypothyroidism?
Dry skin/hair
Goitre
Bradycardia
Slow reflexes
Puffy face
How does severe hypothyroidism present?
Normal symptoms and…
puffy face
large tongue
hoarseness
coma
What are the symptoms of Hyperthyroidism?
Hyperthyroidism:
- Weight loss
- Anxiety/irritability
- Heat intolerance
- Light periods
- Thyroid eye symptoms
What are the signs of hyperthyroidism?
Sweaty palms
Palipitations
Hyperreflexia/Tremors
Goitre
Thyroid eye symptoms/signs
What are the clinical types of hypothyroidism and their differences?
Primary (Thyroid):
- Raised TSH, Low FT4 & FT3
Subclinical (compensated):
- Raised TSH: Normal FT4 & FT3
Secondary (Pituitary):
- Low TSH, Low FT4 & FT3
How common is hypothyroidism?
Commonest endocrine condition after diabetes
1/50 women get it
1/1000 men get it (very rare in men)
Subclinical hypothyroidism quite common in women over 60 (10%)
What are the congenital causes of hypothyroidism?
Developmental:
- Agenesis / maldevelopment
Dysmorphogenesis:
- genetic defects for synthesis of thyroid hormone
How common are congenital causes of hypothyroidism?
1 in 3500 births
- All babies screened in the UK
What are the acquired types of primary hypothyroidism?
Autoimmune:
- Atrophic - most common
- Hashimoto’s thyroiditis
Iatrogenic:
- Postoperative / post- radioactive iodine
- Radiotherapy for head/neck cancers
- Antithyroid drugs, Amiodarone, Lithium, Interferon
Chronic iodine deficiency
Post-partum
What are the causes of secondary hypothyroidism?
Pituitary or hypothalamic damage:
- Pituitary tumour
- Craniopharyngioma - Benign brain tumour begings near the pituitary
- Post pituitary surgery or post radiotherapy
How do you investigate hypothyroidism?
Serum TSH - High TSH confirms primary hypothyroidism
Serum FT4 - Free thyroxine.
Abnormalities of levels of TSH & FT4 - used to determine which type of hypothyroidism
Autoantibodies - TPO (thyroid peroxidase antibodies)
How is hypothyroidism treated?
Levothyroxine - for life, very little side effects. 50 - 150 ug.
Other:
- Liothyronine (T3 replacement)