Endocrinology

Question 1

What is sick euthyroid syndrome?

Answer 1

Low T3/T4 and normal TSH in an acutely unwell patient, during an acute phase of an illness

Question 2

What may cause an increase in TBG?

Answer 2

High oestrogen states e.g. pregnancy, OCP use

Hypothyroidism

Question 3

What may cause a decrease in TBG?

Answer 3

High corticosteroid levels
Protein deficiency states (low intake/decreased synthesis/increased excretion)
Thyrotoxicosis

Question 4

What results will Cushing’s disease show on dexamethasone suppression tests?

Answer 4

Low dose- NO RESPONSE

High dose- SOME RESPONSE

Question 5

What is the insulin tolerance test?

Answer 5

Injection of insulin to induce hypoglycemia.
Testing levels of cortisol and GH.
Test of adrenal function and GH deficiency.

Question 6

What is the clonidine suppression test for?

Answer 6

Presence of phaeochromocytoma.

Plasma free metanephrine levels should be suppressed in people without a phaeo.

Question 7

How do you differentiate between cranial and nephrogenic DI?

Answer 7

Administer desmopressin (synthetic ADH). 
Will correct cranial but not nephrogenic DI!

Question 8

What drugs may cause SIADH?

Answer 8

Carbamazepine

Antipsychotics