Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

724 Clin Path > Adrenal - Ex 4 > Flashcards

Adrenal - Ex 4 Flashcards

1
Q

Canine Hyperadrenocorticism Signs

A
  • middle-aged to older dogs
  • PU/PD
  • Polyphagia
  • Pendulous abdomen
  • Panting
  • Hepatomegaly
  • Muscle weakness
  • Lethargy
  • Lameness
  • Endocrine alopecia
  • Pyoderma
  • Demodex
  • Calcinosis cutis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Canine Hyperadrenocorticism - Lab Abnormalities

A

CBC

  • stress leukogram (neutrophilic, monocytosis, lymphopenia)
  • thrombocytosis

Chem

  • inc ALP (stress)
  • hypercholesterolemia
  • hyperglycemia

U/A

  • USG < 1.020
  • Proteinuria
  • **This helps differentiate from hypothyroidism in dogs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What kind of hyperadrenocorticism do MOST dogs have?

A

85% have pituitary dependent disease

  • excess prod of ACTH = high
  • bilateral adrenocortical hyperplasia (large adrenal glands)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What kind of hyperadrenocorticism do 15% of dogs have?

A

15% have adrenal tumors

  • ACTH = low
  • Unregulated production of cortisol
  • Unilateral adrenal enlargement - one large adrenal gland
  • typically large breed dogs
  • tx: Sx
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Iatrogenic hyperadrenocorticism

A

Chronic Steroid Use

The adrenal glands are fried in these patients - very small

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

Canine Hyperadrenocorticism Dx

A
  1. Rule out Cushing’s
    - Urine cortisol:creatinine ratio (Low - rule out cushing’s; High - cushing’s is differential)
  2. Initial Screening
    - LDDST
    - ACTH Stim Test
  3. Differentiate PDH from ADH
    - HDDST
    - Endogenous ACTH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Urine Cortisol:Creatinine Ratio

A

Cortisol excretion in the urine increases as blood cortisol concentration increases

Sensitive, but not specific

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

With hyperadrenocorticism, the urine cortisol:creatinine ratio will be?

A

Increased

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

Low Dose Dexamethasone Suppression Test (LDDST)

A
  • Dexamethasone
  • inhibits CRH/ACTH/Cortisol
  • Does not interfere w/ cortisol measurement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

In a healthy animal, the LDDST should result in

A

A decrease in cortisol in both 4h and 8hr

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

In a dog with hyperadrenocorticism, the LDDST should result in

A

No change in cortisol (at least no change at 4h)

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

LDDST - HAC dog (PDH)

A

suppression at 4hr but NOT at 8 hr

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

LDDST - HAC dog (PDH or ADH)

A

no suppression at 4 or 8 hr

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

ACTH stim test

A

ACTH stimulates production of cortisol

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

In a healthy animal, the ACTH stim test should result in

A

mild increase in cortisol

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

In a dog with HAC (PDH or ADH), the ACTH stim test should result in

A

A MARKED increase in cortisol

17
Q

In a dog with HAC (iatrogenic), the ACTH stim should result in

A

NO Stimulation! The adrenal glands are gone (atrophy)

18
Q

ACTH stim Interpretation

Mild inc
Exaggerated inc
No inc

A

mild inc: normal

exaggerated inc: Cushing’s

No inc: iatrogenic Cushing’s

19
Q

If both LDDST and ACTH tests are negative…

A

you have ruled out Cushing’s

20
Q

Additional Testing - Endogenous ACTH and HDDST

A

Endogenous ACTH concentration

  • ACTH is unstable and req’s special handling
  • normal to increased ACTH = PDH
  • low to undetectable ACTH = ADH

HDDST

  • Suppression at 4 or 8h = PDH
  • No suppression = PDH or ADH
21
Q

A dog with Cushing’s dz has a low endogenous ACTH concentration, this is most consistent with

A

ADH - HAC

22
Q

A dog with Cushing’s dz has a high endogenous ACTH concentration, this is most consistent with

A

PDH - HAC

23
Q

A dog with Cushing’s dz suppresses w/ HDDST, most consistent with

A

PDH - HAC

24
Q

A dog with Cushing’s dz does not suppress with HDDST, most consistent with

A

HAC, but can’t tell what kind

25
Q

What is the most common equine endocrinopathy?

A

Equine Cushing’s Dz: Pituitary Pars Intermedia Dysfunction (PPID)

26
Q

Equine Cushing’s Dz - Lab Abnormalities

A

CBC

  • stress leukogram
  • anemia

Chem

  • Hyperglycemia
  • Hyperlipidemia
  • Inc liver enzymes
  • Glucosuria
27
Q

Equine Cushing’s Dz - Pathogenesis

A

Pituitary adenoma

Excessive secretion of proopiomelanocortin-derived peptides

  • ACTH, MSH, CLIP & beta-endorphin
  • results in excess cortisol production
28
Q

What is the most accurate test to Dx Equine Cushing’s?

A

Dexmethasone Suppression Test
- most accurate, but no longer recommended!

Dex is assoc’d with laminitis

Lack of plasma cortisol suppression 19-24 hr post dex = Cushing’s

29
Q

Equine Cushing’s Dx - Endogenous ACTH

A

Elevations are suggestive of PPID

30
Q

Equine Cushing’s Dx - TRH Stimulation

A

Theory: cortisol increases 1 hour post TRH with PPID
- cortisol does not inc in most healthy animals

Advantage: no dex administration

31
Q

What tests are NOT recommended to Dx Equine Cushing’s

A

Baseline cortisol
- many horses have normal to dec cortisol levels

Basal insulin levels
- large variation in both PPID and healthy

Urine cortisol:creatinine
- not validated

ACTH stim test

  • not very useful in horses with PPID
  • many PPID horses have low cortisol levels

724 Clin Path (29 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions