Path: Adrenal & Pancreas Flashcards
(47 cards)
What causes most cases of Cushing syndrome?
iatrogenic (exogenous) - drugs force pituitary through negative feedback to reduce ACTH, ZF and ZR atrophy
too much cortisol, not necessarily too much ACTH
Other than pituitary adenoma, what can cause Cushing dz?
corticotroph hyperplasia w/o a mass - pituitary defect or hypothalamus releasing excess CRH
What would the adrenals look like in Cushing dz?
hyperplastic ZF and ZR, compressed ZG, unaffected medulla
maybe nodules, brown or yellow cortical thickening
larger, more vacuolated cells
What findings are present in both primary adrenocortical hyperplasia and neoplasia?
elevated cortisol with low ACTH
What are the characteristics of primary (bilateral) adrenal hyperplasia?
micronodular or macronodular
micronodular - familial, pigmented adrenal nodules, large cortical cells
What are the characteristics of adrenocortical neoplasia?
benign or malignant
almost always unilateral
encapsulated, yellow to black
What are the more common non-endocrine neoplasms that make ACTH?
SCC of lung carcinoid tumor medullary thyroid carcinoma pancreatic islet cell tumors can release CRH, ACTH or mimics = paraneoplastic syndrome
What are some of the normal effects of glucocorticoids?
makes glucose, inhibits insulin action
liver gluconeogenesis and protein catabolism
lipid mobilization
anti-inflammation and stress protection
mineralocorticoid-like effects (due to shared receptor)
What are the clinical manifestations of hypercortisolism?
HTN (due to aldo-like effects) weight gain, truncal obesity, moon facies, fat depo in neck and back atrophy of fast twitch muscles hyperglycemia - due to gluconeogenesis osteoperosis and bone fractures stria, easy bruising immunosuppression (suppresses cytokines) hyperpigmentation
What are the effects of hyperaldosteronism?
causes Na retention and K excretion - pts volume overloaded and hypokalemic
renin and angiotensin down due to feedback on JG cells
What is Conn’s syndrome?
aldo secreting adenoma in adrenal
do not usually suppress ACTH - no atrophy
look for new onset HTN
most common primary hyperaldo
What is the second cause of primary hyperaldo?
primary adrenocortical hyperplasia - ZG
idiopathic
mostly children and young adults
possible CYP11B2 gene overactivity
What causes secondary hyperaldo?
stimulation of RAAS, higher rates of aldo than primary
decreased blood flow to kidney
hypovolemia and edema from other dz
pregnancy
What are the signs and symptoms of hyperaldo?
Na retention
HTN
volume overload
hypokalemia
What is adrenogenital syndrome?
adrenocortical hyperplasia from increased ACTH, may be mixed w Cushings
What can cause adrenogenital syndrome?
adrenocortical adenoma
adrenocortical carcinoma - virilization more often
CAH
What is CAH?
AR mutated CYP21B (21-hydroxylase) enzyme hypocortisolemia stimulates ACTH then bottle neck at defective enzyme and divert down androgen synthetic pathway
What types of adrenal insufficiency are there?
acute and chronic (Addisons) primary
secondary
What can cause acute primary adrenal insufficiency?
Waterhouse-Friderichsen syndrome: massive hemorrhage, children, sepsis by meningococcus (also pseudomonas, staph, strep), maybe endotoxins damage vessels
adults - hemorrhage, stress in setting of chronic
What can cause chronic primary adrenocortical insufficiency?
autoimmune - most common, Ab to 21-hydroxylase or ACTH receptor
inf - tb, fungi w granulomas
AIDS
metastases - bronchogenic, breast
What are signs and symptoms of Addisons dz?
weak, fatigued
dark skin pigment - ACTH released w proopiomelanocortin
nausea, anorexia, weight loss
Na wasting, volume loss, hypotension
hyperkalemia
crisis b/c can’t handle stress - coma or death
What causes secondary adrenocortical insufficiency and what are its signs and symptoms?
reduced pituitary ACTH output
same as primary but no skin pigment or loss of aldo
What are the basics of adrenal adenomas?
can secrete any of the hormones, mixes, or none (rare)
associated w Cushings - <500g, pink ovoid cells
cut surface is yellow
What are findings specific to adenomas causing Cushings?
remaining normal adrenal and contralateral atrophic due to feedback
