Endocrinology Flashcards
What is the most common cause of mortality in diabetic patients?
Cardiovascular disease (macrovascular complications)
What is the difference between Cushing’s Syndrome and Cushing’s Disease?
Cushing’s Syndrome = hypercortisolism due to any cause
Cushing’s Disease = hypercortisolism due to ACTH-secreting pituitary adenoma
Which hormones are secreted by the anterior pituitary?
ACTH, Prolactin, GH, FSH, LH, TSH
Which hormones are secreted by the posterior pituitary?
Oxytocin, ADH (vasopressin)
What are the complications of Cushing’s Syndrome?
Osteoporosis
Diabetes
Hypertension
How is hypercortisolism investigated?
1. Serum cortisol (+/- midnight plasma + salivary cortisol) 2. 24 hour free urinary cortisol 3. 1mg Dexamethasone suppression test 4. 8mg Dexamethasone suppression test
What conditions comprise MEN I syndrome?
Pituitary Tumours
Primary Hyperparathyroidism
Enteropancreatic Tumours
What conditions comprise MEN II syndrome?
Medullary Thyroid Cancer
Phaeochromocytoma
Parathyroid Hyperplasia
What is Zollinger-Ellison Syndrome?
Gastrin-secreting tumour (gastrinoma) formation in pancreas and/or duodenum that causes increased HCl secretion and PUD.
What is Conn’s syndrome?
Aldosterone-secreting adrenal cortex tumour
What are the clinical features of hyperaldosteronism?
Hypertension
Hypokalaemia
Fatigue, weakness, headache, paraesthesia, intermittent paralysis
What is an Addisonian crisis?
Acute adrenal insufficiency (unable to make enough cortisol)
Usually due to abrupt cessation of exogenous steroids
What are the causes of adrenal insufficiency?
Primary: autoimmune destruction of cortex (Addison’s disease)
Secondary: decreased ACTH production or lack of CRH
Which thyroid autoantibodies are associated with Hashimoto’s Thyroiditis and Graves’ Disease?
Hashimoto’s: anti-TPO
Graves’: thyroid stimulating Ig (TSI)
What medical emergencies may develop in thyroid disease?
Thyrotoxic Crisis (hyperthyroidism) Myxoedema Coma (hypothyroidism)
Give 3 differentials for a midline neck lump and how they can be distinguished on physical examination.
Thyroid goitre (moves up on swallowing) Thyroglossal cyst (moves up on poking tongue out) Dermoid cyst (in SC layer, can move skin over the top of it)
Why is it necessary to correct for serum calcium levels?
40% calcium bound to albumin
therefore albumin levels may affect serum total calcium
What clinical signs are used to detect hypocalcaemia?
Trosseau’s sign: carpal spasm
Chovstek’s sign: CN VII
What is the most common cause of secondary hyperparathyroidism?
Renal Failure
decreased excretion of phosphate > suppress serum calcium
What are the features of polycystic ovarian syndrome?
Menstrual dysfunction + infertility
Hyperandrogenism (acne, hirsutism)
Metabolic syndrome
Polycystic ovaries
What is the function of aldosterone?
e.g. Angiotensin II > Aldosterone release > principal cells of DCT > increased activity of Na+/K+ ATPase > increased sodium resorption and potassium excretion
After serum calcium and PTH levels, what is the most useful investigation for hyperparathyroidism?
Sestamibi scan
What is the equivalent average BGL for a patient with a HbA1c of:
(a) 6% (42mmol/L)
(b) 7% (53mmol/L)
(a) 7.0mmol/L
(b) 8.5mmol/L
How is Diabetes diagnosed?
OGTT >11.1mmol/L OR
Random BGL >11.1mmol/L OR
Fasting BGL >7.0mmol/L
Patient must have 2 positive laboratory tests if they are asymptomatic
