Endocrinology Flashcards
What is the most common ectopic thyroid?
lingual (tongue)
Which neck mass is anterior and which is lateral?
thyroglossal cyst is anterior (moving with swallowing and tongue movement) and brachial cleft cyst is lateral
Where are follicular and parafollicular cells derived from?
follicular- endoderm
parafollicular-neural crest (secrete calcitonin)
What is the adrenal cortex derived from? what about the adrenal medulla?
cortex=mesoderm (GFR- aldosterone, cortisol, DHEA)
medulla=neural crest (chromaffin cells-catecholamines-epi/NE)
Does glucose or insulin cross the placenta?
glucose does and insulin does not
What happens to GnRH if you get hyperprolactinemia?
decrease it and thus decrease LH and FSH
Note you want pulsatile GnRH for puberty
What is somatostatin used to treat?
acromegaly, decreases GH and TSH
What does calcitonin do?
Decreases the levels of serum calcium (opposite of PTH)
Secreted by parafollicular cells (C cells of thyroid)
What inhibits T4/T3?
PTU (propylthiouracil) and methimazole
What are the functions of T3?
6 B’s brain maturation, bone growth, B-adrenergic, basal metabolic rate, blood sugar, break down lipids
What can cause pathogenic high ACTH? What will cause high cortisol, but low ACTH?
- ACTH secreting pituitary adenoma
- paraneoplastic syndromes (SCLC, bronchoid carcinoids)
High cortisol, low ACTH
- Bilateral adrenal hyperplasia
- Adrenal adenoma
- Adrenal carcinoma
What are the symptoms of adrenal insufficiency?
can’t make enough mineralocorticoids, glucocorticoids to sustain body’s needs so you get fatigue, orthostatic hypotension, weakness, muscle aches, salt and sugar cravings
What increases in primary adrenal insufficiency?
MSH (hyperpigmentation) in response to elevated ACTH
What is Waterhouse-Friderichsen syndrome?
massive adrenal hemorrhage (neisseria meningitidis) causing primary adrenal insuff
what is the difference between secondary adrenal insuff and primary?
with secondary you have low ACTH, so you don’t get hyperpigmentation with elevated MSH and you don’t get hyperkalemia because you still have an intact renin-angiotensin-aldosterone axis
what is teritary adrenal insuff caused by?
exogenous steroids
what are the causes of secondary hyperaldosteronism?
renovascular disease, juxtaglomerular cell tumours (renin producing tumour)
what is the difference between neuroblastoma and wilms tumour?
wilms tumour is smooth and unilateral, neuroblastoma is irregular and can cross the midline. Neuoblastoma looks for HVA and VMA elevated in urine, Get homer-wright rossetes. Neuroblastoma is a tumour of the adrenal medulla. Arises from neural crest cells.
Pheochromocytoma?
most common adrenal medulla tumour in adults- neural crest cells (chromaffin cells)
- rule of 10’s-10% malignant, bilateral, extra adrenal, kids, calcify
- 5 P’s of symptoms,- pressure, pain, palpitations, perspiration, pallor
- give phenoxybezamine
Whats a VIPoma?
secretes vasoactive intestinal peptide- watery diarrhea, hypokalemia, achlorhydria, associated with MEN-1
What antibodies cause Hashimoto’s hypothryoiditis? What kind of cells do you see on pathology?
antithyroid peroxidase and antithyroglobulin antibodies. Hurthle cells on pathology (lymphoid aggregates with germinal centers)
What are the 6 P’s of congenital hypothyroidism?
pot-bellied, pale, protruding umbilicus, protuberant tongue, poo brain development
-caused by maternal antibodies
What is de Quervain thyroiditis?
post viral illness, subacute granulomatous thyroiditis, very tender, usually after viral illness, high ESR, jaw pain
What is Graves disease?
caused by thyroid stimulating immunoglobulins, HLA DR3 and HLA B8, get tall crowded follicular epithelial cells, scalloped colloid
