Thyroid Dysfunction

Question 1

In what position is a thyroid exam performed?

Answer 1

From behind, each hand on either side of the neck, fingers starting from mid-line moving outward – if normal, thyroid gland should not be felt

Question 2

What is the pre-tracheal fascia?

Answer 2

Attaches the thyroid gland to trachea/larynx = moves thyroid up on swallowing

Question 3

What markers can be used to image the thyroid?

Answer 3

Iodine, technetium

Question 4

What is a lingual thyroid?

Answer 4

Hypothyroid swelling of thyroid cell at base of tongue

failure of normal caudal migration from foramen caecum down to its normal location anterior to larynx and upper trachea.

Question 5

What is a thyroglassal duct cyst?

Answer 5

thyroglassal duct normally disappears

Remnants of epithelium remain and form a cyst – ALWAYS IN MIDLINE MOVES UP ON TONGUE PROTRUSION

Question 6

Nearly all metabolic thyroid disease is due to what?

Answer 6

98% met thyroid (hyper/hypo) disease is due to a primary abnormality of the thyroid gland itself

Question 7

Outline the difference thyrotoxicosis and hyperthyroidism

Answer 7

Hyper = overactivity of thyroid gland. Thyrotoxicosis = too high level of thyroxine hormone

Question 8

What will happen to TSH + T4 during hypo vs hyperthyroidism?

Answer 8

Hypo =
TSH increased
T4 decreased

Hyper =
TSH low
T4 increased

Question 9

What tests can be ordered to assess thyroid function

Answer 9

TSH, free T4

Question 10

What is a goitre?

Answer 10

Occurs during hypo/hyper = thyroid swelling – can be diffuse/multi/single nodular, more common in females, can be physiological (puberty, preg, menopause)

Question 11

What is the comment cause of a goitre?

Answer 11

Iodine def (common in mountainous regions) = reduced throxine leads to increased TSH whoch leads to thyroid enlargement

Multi-nodular goitre (western pop)

Question 12

Why is iodine def particularly a concern in preg women?

Answer 12

Child = mental retardation, abnormal gait, deaf, short, goitre, hypothyroidism

Question 13

What are the poss consequences of a multi-nodular goitre?

Answer 13

may enlarge inferiorly into superior
mediastinum to form a retrosternal goitre = may cause tracheal
compression

Question 14

What are the signs and symptoms of hypothyroidism?

Answer 14

Excessive tiredness, weight gain, memory problems, constipation, cold intolerance, horse voice, dry skin, hair loss, muscle weakness, non-pitting oedema, cold sweaty hands, MENORRHAGIA

Loss of outer third eyebrows, myxoedema facies

Question 15

What is myxoedema?

Answer 15

Means deposition of lipopolysaccharides in the skin – but has come to mean hypothyroid

Question 16

Outline some causes of hypothyroidism

Answer 16

Autoimmune destruction (Hashimotos),

severe iodine def,

post surgical removal of thyroid

Question 17

How is hypothyroidism treated?

Answer 17

Give thyroxine, not destroyed by immune system, adjust dose to normalise serum TSH

Question 18

Outline the symptoms of hyperthyroidism/thyrotoxicosis

Answer 18

Overactivity, anxiety, warm sweaty hands, palpitations, shaking, weight loss, AMENORRHEA

Question 19

What are the signs of thyrotoxicosis?

Answer 19

Weight loss, warm sweaty hands, fine hand tremor, bounding pulse, lid lag, staring eyes

Question 20

What are the causes of thyrotoxicosis due to hyperthyroidism?

Answer 20

Graves, toxic multi-nodular goitre, toxic adenoma

Question 21

What is graves disease?

Answer 21

Autoimmune disease: thyroid stim Ig (TSI) against TSH receptor = classical signs/symptoms of thyrotoxicosis + exophthalmos (abnormal protrusion of the eyeball or eyeballs) + pre-tibial myxoedema

Question 22

What is the 2nd most common cause of a hyperthyroidism?

Answer 22

Toxic multi-nodular goitre – not autoimmune

Question 23

What is a toxic adenoma

Answer 23

very rare benign tumour of glandular epithelial tissue - produce TSH and lead to thyrotoxicosis

3rd most common cause of hyperthyroidism, single enlargement that starts to work autonomously

Question 24

Which condition is treated with carbimazole?

Answer 24

Hyperthyroidism

Question 25

What signs would indicate Graves’ disease over other types of hyperthyroidism?

Answer 25

Exopthalmos

Pre-tibial myxoedema