adrenal Flashcards
what does the adrenal cortex produce
corticosteroids
what does the adrenal medulla produce
catecholamines
zona glomerulosa
outermost area and is responsible for making aldosterone
zona fasiculata
middle zone and is responsible for making imactive cholesterol
zona reticularis
innermost zone and is responsible for making glucocorticoids including cortisol and corticosterone and androgens
what is hyperadrenalism
with aldosterone (hyperaldosteronism which is conn’s syndrome)
with cortisol - cushing syndrome
with androgens- adrenogenital syndromes
what is primary hyperadrenalism
excessive secretion of aldosterone independent of the renin angiotensin system , also known as conn’s syndrome
what are the causes of primary hyperadrenalism?
bilateral hyperplasia of the cortex
aldosterone secreting adenoma
rarley a carcinoma
what are the clinical features of conn’s syndrome or primary hyperaldosteronism ?
Hypernatraemia , hypokaleamia , high blood pressure, muscle weakness, cardiac decompensation and ecg changes
function of angiotensin II ?
stimulation of the release of aldosterone and acts as a vasocnstrictor
what is secondary hyperaldosteronism?
is the adrenal response to increased renin angiotensin levels ( renin angiotensin dependent)
what are the causes of secondary hyperadrenalism?
renal ischaemia chronic oedema (nephrotic syndrome and ascites)
what is cushing syndrome ?
is a chronic excess of cortisol production
what causes cushing syndrome ?
prolonged treatment with glucocorticoid such as predinsolone
pituitary hyper-secretion of ACTH ( cushing disease)
ectopic secretion of ACTH : non pituitary such as small cell carcinoma
glucocorticoid hyper-secretion by an adrenal adenoma or adrenal hyperplasia or adrenal carcinoma
what controls cortisol levels
ACTH
what are the clinical features of cushing syndrome ?
truncal obesity moon face hirsutism hypertension polycythaemia diabetes/glucose intolerance abdominal stria menustal abnormalities
what is CAH
congenital adrenal hyperplasia - congenital metabolic errors where an enzyme involved in steriogenesis is missing, which results in the increased formation of androgens resulting in virilization (deficiency in 21-hydroxylase)
what are the three possible syndromes with 21 hydroxylase deficiency ?
salt wasting adrenogenitalism
simple virilizing adrenogenital syndrome
non classic adrenal virilisim
what is salt wasting adrenogenitalism ?
complete lack of 21 hydroxylase , cardiovascular collapse, virilization of females and precocious puberty in males
what is simple virilizing adrenogenital syndrome ?
subtotal deficiency in 21 hydroxylase, decreased level of aldosterone but still sufficient for salt reabsorption, not enough glucocorticoids for ACTH suppression , so high levels of ACTH
what is non classic adrenal virilism
mild deficiency and may be asymptomatic only diagnosed by genetic studies
presentation of CAH in girls ?
newborn girls are born with an enlarged clitoris with the urethral opening at the base and start to shoow signs of masculinization as they grow older, internal structures remain normal
boys with CAH?
may appear normal as anew born but start to show signs of masculinaztiona nd puberty at a very early age but the testes eventually are small once they reach puberty
what is primary acute hypoadrenalism caused by?
a form of hypoadrenalism caused by rapid qwithdrawal from steroid therapy , sepsis or massive destruction of the adrenals, adrenal haemorrhage
what is waterhouse-friderichson syndrome
is a group of symptoms resulting from the failure of the adrenal glands to function normally as a result of bleeding into the gland usually caused by meningiococcal bacteria
what is primary chronic adrenal insufficiency
also known as addisons disease
causes of addisons disease ?
autoimmne , TB , metastases , amyloid , lymphoma
what are the clinical features of Addison’s disease?
bronze pigmentation of the skin, hypoglycaemia, postural hypotension, weight loss, change in distribution of body hair
what are the causes of secondary cortical adrenal insufficiency?
any disorder of the hypothalamus or thr pituitary that may cause a decrease in ACTH secretion
what are the clinical features of secondary adrenocortical insufficiency
similar to that of Addison’s without the hyper pigmentation ( Low ACTH production)
do patients with 2ry adrenocorticall insufficiency have hyponatraemia or hyperkalemia ?
no because aldosterone levels are unaffected as it is not ACTH dependant
what are the most significant disorders of the adrenal medulla
neoplasma ; pheochromocytoma, neuroblastoma, ganglioneuroma
what are the familial syndromes associated with pheochromocytoma ?
MEN type 2
MEN type 3
Von-Hippel Lindau
Von Recklinghausen or neurofibromatosis
Struger-Weber
what is the origin of pheochromocytoma ?
chromaffin cells
what does pheochromocytoma cause clinically ?
catecholamine induced hypertension which can be cured by excision
