Endocrine

Question 1

Cushings - signs

Answer 1

pot belly - increased fat and weakening abdominal wall muscles
polyphagia
lethargy
crusty skin
alopecia
exercise intolerance
muscle wastage
PUPD

Question 2

HPA Axis

Answer 2

hypothalamus - Corticotropin releasing hormone and vasopressin
anterior pituitary - adrenocorticotropic hormone
adrenals - glucocorticoids

negative feedback loop

Question 3

cushings - testing

Answer 3

bloods -
stress leukogram
increased ALT and ALP
high cholesterol

urinalysis -
low USG
urine cortisol:creatinine

ACTH stim - high cortisol positive
low dose dexmethasone suppresion test

Question 4

low dose dexamethasone suppression test

Answer 4

baseline cortisol
give dex
sample again - 4 and 8 hours

differentiate adrenal and pituitary dependent cushings

adrenal - high cortisol both times
pituitary - suppresses at first sample then rises quickly again

don’t use if iatrogenic cushings or stressy dog

Question 5

cushings - adrenal dependent

Answer 5

adrenal tumour
may have low ACTH because of cortisol negative feedback
adrenal with no tumour may be smaller
large breeds more common

Question 6

cushings - pituitary dependent

Answer 6

pituitary tumour
produces ACTH without stimulation
high endogenous ACTH
more common in smaller breeds

Question 7

hyperthyroidism - comorbidities

Answer 7

congestive heart failure - increased GA risk, prolonged sympathetic stimulation
renal disease - may be masked by increased BP from hyperthyroidism then become apparent when treated
diabetes - increased peripheral insulin resistance

Question 8

hyperthyroidism - treatment

Answer 8

thiamazole - reduces thyroid hormone synthesis
carbimazole - same function as above

diet - low iodine - aim being so they can’t make as much thyroid hormone

surgery - thyroidectomy with various levels of parathyroid preservation (best to keep as much as possible but important not to leave any tumour tissue)

radioactive iodine - gold standard, but can’t go near them for a few days after

Question 9

hyperthyroidism - treatment monitoring

Answer 9

oral meds -
serum T4 at 2-3 weeks after start of treatment
serum T4, biochem and hematology at weeks 4, 8 and 12 after table
urinalysis and BP ever 3-6 months - for renal disease and diabetes

diet -
serum T4 at 4 weeks - check levels decreasing
check monthly
can take a long time to work

surgery -
2 weeks post surgery
1, 3, 6, 12 months after

radioactive iodine - as for surgery
TSH if signs of hypothyroidism

Question 10

hypothyroidism - comorbidities

Answer 10

cardiac disease - doesn’t cause but can impact already deficient function
diabetes - immune mediated, associative rather than causative - makes diabetes more difficult to treat
hypoadrenocorticism - treatment may lead to adrenal crisis if existing issue (check for both)
myxodema coma - rare but serious sequelae - comatose, cold, slow heart, low BP, hypoventilation

Question 11

hypothyroidism - treatment

Answer 11

levothyroxine - synthetic thyroid hormone - tablet or liquid

not with food - decreases drug absorption

Question 12

hypothyroidism - treatment monitoring

Answer 12

total T4 4-6 hours after medication
monitor for clinical signs

if T4 normal but still showing signs - check circulating TSH

Question 13

cushings - cats

Answer 13

usually presents as insulin resistant diabetes
treatment not very successful
surgery difficult and risky

(Refer)

Question 14

cushings - treatment

Answer 14

trilostane - oral - decreases cortisol and aldosterone production (have to get little ones made special for very small patients, can’t break them up)

surgery - adrenalectomy - only if adrenal dependent, not often done and only if unilateral

radiotherapy - macroadenomas only

Question 15

cushings - monitoring treatment

Answer 15

ACTH stim - pre treatment and then at 10 days, 4 weeks, 12 weeks
then every 3 months

measures 4-6 hours after dosing

Question 16

Addisons

Answer 16

uncommon in dogs, rare in cats
underproduction of glucocorticoids
predisposed breeds - poodle, portuguese water dog

Iatrogenic addisonian crisis - risk when coming off steroids too fast

Question 17

Addisons - comorbidities

Answer 17

hypothyroidism - treatment for hypothyroidism can predispose to Addisons

sequelae - addisonian crisis

Question 18

Addisonian crisis

Answer 18

hypovolemic shock
brady or tachycardia
collapse
depression
hypothermia

rapidly progressing and life threatening
if undiagnosed before go into crisis - probably just die

Question 19

Addisons - signs

Answer 19

random signs, all the things
hard to spot

Question 20

Addisonian crisis - treatment

Answer 20

fluids to stabilise shock - until eating, also helps resolve hyperkalemia
IV steroids
glucose CRI - for hypoglycemia

Question 21

Addisons (non-crisis) - treatment

Answer 21

prednisolone - titre to lowest effective dose, increase at known stress periods

zycortal - monthly injection, complicated to monitor

Question 22

diabetes mellitus - comorbidities

Answer 22

hypothyroidism - associative
obesity
acromegaly
hypoeradrenocorticism (cushings)
pancreatitis
other inflammatory disorders

any condition that increases peripheral insulin resistance

Question 23

diabetes mellitus - complications

Answer 23

diabetic neuropathy - glucose build up in nerves, plantigrade stance

UTIs - glucose in urine feeds bacteria

ocular disease - cataracts in dogs, retinal neuropathy in cats - to do with osmotic balance

diabetic ketoacidosis - in uncontrolled cases, life threatening

Question 24

diabetic ketoacidosis - signs

Answer 24

uncontrolled diabetic
pupd
vomiting
lethargy
anorexia
tachypnoea
acetone breath
dehydration
hypothermia
coma - late stage

Question 25

diabetic ketoacidosis - testing

Answer 25

urinalysis - glucose, kerones
serum - ketones and glucose
metabolic acidosis

Question 26

diabetic ketoacidosis - treatment

Answer 26

correct dehydration - fluids

address electrolytes and acid base - phosphate, calcium and magnesium
can give bicarb but usually sorts itself and can cause alkalosis

once sorted all that -
insulin - monitor every 2 hours

identify underlying cause - usually a concurrent disorder (pancreatitis, UTI, cushings, CKD, hepatic lipidosis, cholangiohepatitis)
check medication is actually being given properly

Question 27

diabetes mellitus - treatment

Answer 27

diet -
control obesity
energy from protein and fat - decrease post prandial glucose increase
can’t use high protein in pancreatitis or CKD

oral hypoglycemics -
cats only
stimulates insulin secretion from pancreas
not very effective, esp over time
good in exotics

velagliflozin -
stops reuptake of urine after filtration
controls signs
may cause diarrhoea - but usually self limiting
risk of UTI from glucose in urine
can still go into ketosis - glucose not going into cells, just being peed out

insulin therapy -
best
caninsulin - pig insulin - injectable by owner, better in dogs than cats
prozinc - human insulin - kept in fridge, not shaken

ovariohysterectomy -
along with insulin therapy
just because diabetes harder to control in entire females

Question 28

diabetes mellitus - treatment monitoring

Answer 28

owner diary - doses, food, water, demeanor, weight, BCS

blood glucose curves - 12 weeks after treatment start

continuous glucose monitoring

serial fructosamine measurements