Scenario 16 Flashcards
Defeciency of TRH is a …. Deficiency of thyroid axis?
3
A deficiency in TSH is a …. Deficiency of the thyroid axis
2
A deficiency in t3/4 is a …. Deficiency of the thyroid axis
1
A person with low T4 and high or low TSH is…
Hypothyroid
A person with high T4 and low/ normal TSH is
Hyperthyroid
A person with thyrotoxicosis has …
High T4 and low TSH
Hashimotos affects …% of the population?
3
Hashimoto’s thyroiditis is a disease resulting from….
Autoimmune Ig against thyroglobulin or thyroid peroxidase
What level of iodine leads to non-toxic goitre?
Less than 50 micrograms per day
2 drugs to treat hypothyroidism
Thyroxine and liothyronine
What is a goitrogen?
A substance that suppresses the function of the thyroid by interfering with iodine uptake
How long does it take for a person taking anti thyroid drugs to become euthyroid?
4-8 weeks
How long is treatment for graves with anti thyroid drugs maintained?
12-18 months
2 anti thyroid drugs
Carbimazole and propylthiouracil (prevent conversion from T4–>T3)
Side effects- neutropenia and agranulocytosis
What is used to treat hyperthyroidism by radiation and what is its half life?
Radio iodine and 8 days
When do you use radio iodine to treat hyperthyroidism?
Failed drug treatment, need for urgent treatment, toxic nodules
What sequence of events leads from iodine deficiency to hyperthyroidism?
Iron deficiency leads to decreased T4,thyroid cell hyperplasia, mutation of TSH receptor to constitutively active form
What cytokine induces bystander activation in autoimmune thyroid disease?
TNF alpha
What causes Graves?
Autoimmune Ig acting as TSH receptor agonist
What are the effects of cortisol?
Increase blood glucose levels, increase gluconeogenesis, increase the use of fatty acids for energy and decrease the use of glucose for energy
What does the zone glomerulosa secrete?
Aldosterone
What does the zone fasciculata secrete?
Cortisol
What does the zone reticularis secrete?
Weak androgens
What input does the adrenal medulla receive?
Cholinergic pre ganglionic sympathetic input