Endocrine

Question 1

Pathophysiology of canine diabetes mellitus

Answer 1

Pancreas does not make insulin (similar to type I in people). Usually immune-mediated or secondary to pancreatitis. Middle-aged dogs predisposed.

Question 2

Canine diabetes mellitus treatment

Answer 2

Goal: control clinical signs and improve quality of life
No remission possible
Tx: Insulin (vetsulin) begin at 0.25-0.5 U/kg q12h, high fiber diet, glucose curves to guide treatment (helps void underdosage/overdosage)

Question 3

How would glucose curves help identify the somogyi effect?

Answer 3

The somogyi effect is when the animal is on too much insulin. This leads to a drop in BG which the body responds by releasing glucagon to spike BG. On “spot checks” this may lead us to think the patient is being UNDERdosed.. but in reality the patient is being OVERdosed!

Question 4

DKA pathophysiology

Answer 4

Mismanaged DM leading to a lack of insulin for glucose uptake. The cells are starved leading to fat breakdown and ketone build-up

Question 5

DKA clinical pathology findings
Glucose ___
Potassium ___ or ___
Na ___
AG ___

Answer 5

Glucose HIGH
Potassium HIGH (no cellular uptake) or LOW (anorexia)
Sodium LOW (fluid shift into vasculature)
AG HIGH (KLUE)

Question 6

DKA Treatment

Answer 6

IV fluids
Electrolyte correction
Fast acting insulin (CRI)
Dextrose (resolve the ketonemia)
Potassium ALWAYS given with insulin CRI

Question 7

Hyperadrenocorticism (Cushings) etiology

Answer 7

Pituitary dependent tumor (85%) PDH
Adrenal dependent tumor (15%) ADH
Iatrogenic (excessive corticosteroids)

Question 8

Cushing’s clinical signs

Answer 8

muscle weakness/atrophy, alopecia, comedones, abdominal distention, hepatomegaly, thin skin, calcinosis cutis

Question 9

Cushing’s clinical pathology
_____ leukogram
_____ ALP, ALT, Triglycerides
_____ BUN
_____ Creatinine

Answer 9

stress leukogram (neutrophils and monocytes HIGH, lymphocytes and eosinophils LOW)
LOW BUN (cortisol inhibits ADH causing washout)
LOW Creatinine d/t muscle wasting

Question 10

LDDST (how to perform, expected results for PDH vs ADH)

Answer 10

Baseline, 4 hr, 8 hr sample
PDH - will see suppression (drop in 4 hr) and then huge spike in 8 hr
ADH - will NOT see any suppression for any sample

Question 11

ACTH stimulation test (expected results for cushings vs addisons)

Answer 11

Cushings - will see exaggerated response
Addisons- no response

Question 12

Cushing’s Tx (two main drugs & their mechanism)

Answer 12

Mitotane - cytotoxic adrenocortical destruction
Trilostane - inhibit cortisol synthesis

can ultrasound abdomen to look for adrenal mass

Question 13

Addison’s disease gender predelection

Answer 13

70% Female

Question 14

Addison’s pathophysiology and clinical signs

Answer 14

Decreased production of cortisol and aldosterone

Anorexia, lethargy, thin condition, PU/PD, diarrhea, collapse, bradycardia (tall T waves), shaking, low SG

Question 15

Addison’s clinical pathology
Anemia
Lack of ____ leukogram
K __
Na/Cl __
ALT/AST/ALP __
USG __

Answer 15

Lack of stress leukogram
High potassium
Low na/cl
High liver enzymes
USG < 1.030

Question 16

Addison’s diagnosis (test and expected result)

Answer 16

ACTH Stim < 2 (baseline AND post-injection)

Question 17

Addison’s treatment

Answer 17

Fluids (normal saline best choice)
Hyperkalemia Tx (insulin + dextrose, calcium gluconate)

Prednisone (corticosteroid replacement)
Fludrocortisone (mineralocorticoid aka: aldoserone replacement)

Question 18

Canine hypothyroidism clinical signs

Answer 18

Weight gain, alopecia (trunk, tail, ventral thorax), pyoderma, hyperkeratosis, bradycardia, weak pulses, lethargy, obesity

Question 19

Hypothyroidism
TSH _
TT4_
FT4_

Answer 19

TSH high
TT4 low
FT4 low

Note: if TSH is in normal range and TT4/FT4 are both low, that is highly suspicious for hypothyroidism!

Question 20

Hypothyroidism Tx

Answer 20

Levothyroxine :)

Question 21

Low ___ and ___ leads to medullary washout and low USG.

Answer 21

BUN , Na

Question 22

Why do we see a low USG with addison’s disease?

Answer 22

low aldosterone - leading to low sodium - leading to medullary washout