Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Endocrinology - 2nd year > Cushing's, Addison's and Pheochromocytoma > Flashcards

Cushing's, Addison's and Pheochromocytoma Flashcards

(67 cards)

Start Studying
1
Q

85-95% of endogenous cushing’s dogs and cats are due to ____.

A

Pituitary-induced micro or macroadenoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Cushing’s pathogenesis

A

XS ACTH made in pituitary –> adrenals –> hypercortisolemia (pituitary escape from negative inhibition)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Adrenal steroidogenesis

A

ACTH –> adrenal cortex –> aldosterone, cortisol and sex steroids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Atypical cushing’s

A

normal cortisol levels, cushings symptoms caused by xs intermediate metabolites from steroidogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the three zones of the adrenal cortex?

A

Glomerulosa
Fasciculata
Reticularis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What hormone is made in the zona glomerulosa?

A

aldosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What hormone is made in the zona fasciculata?

A

cortisol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What hormone is made in the zona reticularis?

A

ketosteroids and cortisol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Aldosterone has an effect on _____.

A

Na and K production in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pathophysiologic effects of xs cotisol?

A

Muscle/bone/tendon - weakness
liver - glycogen deposition; steroid hepatopathy
gut - hyperacid secretions
immune system - suppressed, prone to secondary infection (silent UTIs)
kidney - PU/PD because ^GFR and renal plasma flow
Brain - hyperirritable. Dog: panting!
Bloodstream - mature neutrophilia, lymphopenia, eosinopenia, monocytosis, thrombocytosis, and increased RBCs
Lipid metabolism - increased cholesterol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Breed and age incidence of Hyperadrenocorticism?

A

toy and miniature breeds (poodles and dachshunds)

age: 3-13 range, avg 8 years old

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

main endogenous causes of Hyperadrenocorticism?

A 
pituitary dependent (high ACTH, high cortisol)
adrenal dependent (low ACTH, high cortisol)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

exogenous cause of Hyperadrenocorticism?

A

iatrogenic - large doses of glucocorticoids (act like cortisol)

** must wean off these drugs because will have trouble making cortisol with removal of drug.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Physical features of Hyperadrenocorticism?

A

Panting (dogs)
PU/PD
pendulous abdomen (due to muscle weakness)
stria (stretch marks) from weakening/thinning of skin
truncal alopecia with hyperpigmentation
acne formation - keratin plugging of hair follicles
easily bruise
calcinosis cutis
cushings wrinkles
general muscle weakness- myotonia!
lethargy
polyphagia
testicular atrophy and hepatomegaly in the dog due to glycogen accumulation
hypercoagulable

Other: pulmonary calcification, prothrombotic tendency, hypertension, proteinuria, glomerulopathy (can be permanent)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Hyperadrenocorticism lab findings?

A

mature neutrophilia, eosinopenia, and lymphopenia
Polycythemia
high liver enzymes (hepatomegaly due to glycogen accumulation)
glucose (if also have DM)
+/- pyuria —> UTI
+/- hematuria
Proteinuric (glomerulopathy)
hypertension (glomerulopathy)
high cholesterol/TGs (lipemia)
high cortisol
adrenal/pulmonary calcification (gritty lungs on necropsy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Cushing’s imaging

A 
radiographs
early phase pyeologram 
arteriography
abdominal U/S
pituitary CT/MR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

If unilateral adrenal tumor is resected, the ipsilateral adrenal will be atrophied so expect _____ post-op.

A

adrenocortical insufficiency - supplement glucocorticoids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

pituitary macroadenomas are hard to resect; try to remove whole pituitary which means will have _____ post-op.

A

diabetes insipidus (no renal ADH) or another hypoendocrinopathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Cushing’s diagnosis

A 
Urine cortisol/Cr ratio (if negative, rules out cushing's, if positive, could be something other than cushing's) 
ACTH stim test***
LDDT - low dose dex suppression 
HDDT
Plasma ACTH - \$\$$ and time
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Most common signs of cushing’s in a dog?

A

PU/PD, pendulous abdomen, and panting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

ACTH stim test

A

hyperstimulation of ACTH (cortisol) is positive for cushings. (>20)
Doesn’t specify if pituitary or adrenal cushings, do LDDT/HDDT to determine which.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

LDDT and HDDT

A

should suppress cortisol to <1.7
If suppresses but not below 1.7, then pituitary cushings.
If does not suppress at all, then adrenal tumor.

20% of PDH will not suppress HDDT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

cushing’s treatment?

A
  1. surgical removal of hypothalamus or adrenal gland
  2. medical - OPDDD (dogs) and Trilostane (dogs and cats) suppress cortisol production. Lysodren and Metotane are OPDDD drugs.
  3. Iatrogenic - stop the steroids (taper off)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How to prove iatrogenic cushing’s?

A

hold off pred, do ACTH stim test –> no response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
OPDDD drug interactions?
It is metabolized in the liver by cytochrome P450 so anything that affects this will affect its metabolism. Phenobarbital makes OPDDD ineffective because enhances P450 metabolism
26
OPDDD cytotoxicity?
Adrenocorticolytic --> if destroy adrenal cortex, end up with Addison's.
27
Lysodren _____ sometimes necessary
reloads
28
OPDDD side effects
drug toxicity - depression, weakness, vomiting, anorexia, and diarrhea --> stop use ---> signs go away --> start again on lower dose addison's disease pituitary tumor growth - nelson's disease (micro-->macro), pituitary apoplexy (sudden death)
29
Trilostane
most popular drug for PDH | adrenal enlargement due to increased intermediate metabolites from steroid synthesis
30
Cushing cat is similar to the dog, but many are ______.
Diabetic, may require insulin, thin/friable skin
31
Cushing cat diagnostics are difficult because?
ACTH stim not sensitive, HDDT>ACTH stim
32
Most common cause of cushingoid dog?
Overtreatment with glucocorticoids
33
Pheochromocytoma incidence?
rare | 50% benign 50% malignant
34
Pheochromocytoma arises from ____.
adrenal medulla
35
Pheochromocytoma signs usually due to _____.
catecholamine secretion or postcaval obstruction
36
Pheochromocytoma clinical signs?
Paroxysmal (periodic and severe) anxiety, mental depression, restlessness and panting. Also blanching, flushing, weakness and/or collapse. Tachycardia +/- VPCs, tachyarrythmia or CHF ascites --> post caval invasion by tumor hyphema (blood in eye)
37
Pheochromocytoma ddx?
hypoglycemia cardiac disease cerebral dysfunction hyperthyroidism
38
Pheochromocytoma dx?
``` history and physical exam! imaging (rads, U/S, CT) BP measurements strong index of suspicion - old dog with unexplained tachyarrhythmia elevated urinary normetanephrine ```
39
Pheochromocytoma treatment?
surgery | medicine: phenoxybenzamine (alpha blocker), regitine aka phentolamine (alpha blocker), propanolol (beta block)
40
If dog is hypertensive and tachyarrhythmic, do what?
ALPHA BLOCK BEFORE YOU BETA BLOCK
41
To increase surgery survival, you should?
Start phenoxybenzamine 2 weeks before to stabilize BP
42
Aldosteronoma more common in?
Cats >> dogs but overall it's rare
43
Aldosteronoma is neoplasm of the?
zona glomerulosa of the adrenal cortex
44
Aldosteronoma clinical signs?
XS Na retention --> hypertension --> retinal hemorrhage and blindness XS K excretion --> hypoK effects PD/PU
45
Other causes of hypertension in a cat?
chronic renal insufficiency | hyperthyroidism
46
Addison's is also called?
Hypoadrenocorticism
47
Cushing's is also called?
Hyperadrenocoticism
48
Addison's incidence?
Not common, mostly in dogs <5 years old
49
Causes of adrenocortical insufficiency?
``` iatrogenic - glucocorticoids induce atrophy infiltrative - cancer, mycoses infarction pituitary insufficiency OPDDD induced destruction Idiopathic Autoimmune destruction Cosyntropin - really rare ```
50
Sign that it is autoimmune?
adrenal cortex significanly diminished with lymphocytes and plasma cells invading on cytology
51
Relative adrenocortical insufficiency
septic patient has cytokines that can decrease glucocorticoid release from adrenals which leaves critically ill and dying patient with no glucs needed to maintain BP and live
52
atrophic zona fasciculata, what happens?
decreased cortisol --> decreased gluconeogenesis, decreased sensitivity to catecholamines, decreased water diuresis, decreased appetite, increased eosinophils and lymphocytes, decreased cerebration
53
atrophic zona glomeruloa, what happens?
decreased aldosterone --> excrete Na and retain K --> hyperK and low BP
54
Electrolyte markers for addison's?
HyperK and HypoNa (together are really bad for heart)
55
Hypoadrenocorticism dx?
history and clinical findings | ECG changes
56
Addisonian crisis signs?
history of weight loss, lethargy, decreased appetite, and GI signs presents weak or in collapse mentally dull bradycardia while hypotensive!! (<60 bpm) weak femoral pulse may clinically resemble acute uremic state
57
Addisonian crisis lab findings?
``` +/- netropenia, eosiniphilia, and lymphocytosis hyperK hypoNa high BUN low bicarb +/- hypocholesterolemia +/-hypoalbuminemia +/- hypercalcemia highly variable, not reliable for dx ```
58
Pseudoaddisons?
anything that causes low Na and high K Renal dz GI dz DKA, HNKD Chylothorax
59
Addison's dx?
Na/K <20 ACTH Stim test*** gold standard Cortisol:ACTH ratio Aldosterone:Renin ratio
60
Plasma ACTH determination?
Primary addisons - ACTH high | Secondary Addison's - ACTH low
61
When in crisis, need to treat immediately, what is the drug you go to first? Why?
Dexamethasone over pred because won't interfere with cortisol assay
62
Simultaneous treatment and dx for addisonian crisis
1. begin IV NaCl 2. collect resting serum cortisol 3. give ACTH 4. give dex IV 5. collect 2nd serum cortisol
63
Maintenance treatment for Addison's
Florinef (both mineralocorticoid and glucocorticoid) Prednisone DOCP (only mineralocorticoid) - if OD, get hypoK
64
Atypical addison's
chronic lethargy, weakness, poor appetite, weight loss normal Na and K despite low aldosterone*** absent ACTH stim response
65
atypical Addison's treatment?
because normal electrolyes, just give pred
66
Any medical or surgical stress to an Addisonian will warrant use of significant supplemental doses of ___.
glucocorticoids
67
causes of atypical addison's
secondary adrenocortical insufficiency | immune destruction of z. fasciculata or glomerulosa

Endocrinology - 2nd year (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions