Disorders Of Adrenocortical Function Flashcards
What is congenital adrenal hyperplasia?
Impaired cortisol synthesis due to a deficiency of one of the 5 enzymes needed for cortisol synthesis
Where are adrenaline and noradrenaline made?
Adrenal medulla
What are the three stages of cushings disease investigation?
Screening, confirmation and differentiation of the cause
What are the three differential diagnosis for positive screening?
True Cushing’s syndrome, pseudo Cushing’s syndrome and exogenous steroids
What are the symptoms of pseudocushings syndrome?
Depression, alcoholism, anorexia and obesity
When does ectopic ACTH production happen?
When the neuroendocrine cells become malignant
What happens in terms of aldosterone and cortisol in extreme situations (like bleeding to death)?
You dont have enough aldosterone so cortisol oversaturates the cortisol -> cortisone enzyme and then causes sodium retention
What imaging do you do for a pituitary tumour?
MRI or inferior petrosa sinus sampling
What imaging do you do for an adrenal tumour?
CT or MRI
What imaging do you do for an ectopic tumour?
ACTH sampling or octreotide scan
What is an octreotide scan?
Putting a nuclear tracer on somatostatin
Why do patients need to take steroid replacement tablets when they have tumour removal surgery?
The tumour suppresses the glands ability for secretion, so it needs time to replenish
What are some of the causes of addisons syndrome?
Autoimmune, TB, steroid withdrawal, metastasis, infiltration, apoplexy, infection, enzyme defect and drugs
What are the four dynamic tests for adrenal insufficiency?
Short Synacthen, long synacthen test, insulin tolerance test and glucagon test
What are the two treatments for Addison’s disease?
Hydrocortisone and fludrocortisone
What is the most common deficiency in congenital adrenal hyperplasia?
21- hydroxylase
Why is lots of testosterone produced in congenital adrenal hypoplasia?
No cortisol means no negative feedback and lots of ACTH -> lots of cholesterol -> lots of testosterone
What does excess testosterone cause?
Virilisation, hirsutism, infertility
What does 11 beta hydroxylase deficiency cause?
No aldosterone or cortisol but high deoxycorticosterone and testosterone
How do you test for congenital adrenal hypoplasia?
Synacthen test or prednisone suppression
What would you see in the synacthen test in a 11 beta hydroxylase deficient patient?
No cortisol rise and increased 17OH progesterone levels
What should happen in a prednisone suppression test?
Androgens should fall into normal range
How do you treat congenital adrenal hypoplasia?
Glucocorticoid therapy, surgery to virilised female genetalia and treatment of mother to prevent foetal virilisation
Where is aldosterone produced?
Zone glomerulosa of the adrenal cortex
What are the clinical signs of primary excess aldosterone syndromes?
High aldosterone and low renin
What are the clinical signs of secondary excess aldosterone syndromes?
High aldosterone and high renin
What are the names of some primary aldosterone excess syndromes?
Conn’s, bilateral adrenal hyperplasia, steroid treatable hypertension and aldosterone producing adrenal carcinoma
What are the names of some secondary aldosterone excess conditions with hypertension?
Renal artery stenosis, renin secreting tumour, malignant nephrosclerosis
What are the names of some secondary aldosterone excess conditions with a normal BP?
CCF, cirrhosis, nephrotic syndrome and dehydration
What is a phaeochromocytoma?
Tumour of the enterochromaffin cells of the adrenal medulla
Where do extra adrenal phaeochromocytomas occur?
In sympathetic ganglia or organ of zuckerkandl
What catecholamines do phaeochromocytomas produce?
Adrenaline, noradrenaline and dopamine
What is the rule of 10 with phaeochromocytomas?
10% bilateral, 10% malignant and 10% extra adrenal
What are some phaeochromocytoma- associated syndromes?
Neurofibromatosis type 1, von hippel-Lindau disease, multiple endocrine neoplasia type 2, hereditary paraganglioma syndrome
Why is the thyroid gland removed in multiple endocrine neoplasia type 2 patients?
Stop the formation of a medullary thyroid carcinoma
What are the main symptoms of phaeochromocytoma?
Sweating, headache, tachycardia
What are the pharmacological symptoms of phaeochromocytoma?
Eosinophilia, hyperglycaemia, hypercalcemia, raised urinary metonephrines and catecholamines
What types of drugs are used to manage phaeochromocytomas?
Alpha and beta blockade
