Final Exam--SA material Flashcards
In most cases, feline hyperthyroidism is due to?
adenoma of thyroid gland
*usually bilateral
The most common physical exam finding in cats with hyperthyroid?
palpable goiter
T/F: Feline hyperthyroidism can cause marked elevations in liver enzymes
False
*MILD increases (up to 400s)
How can you determine if feline thyroid nodules are malignant?
histopath is ONLY definitive way
*radionuclide scan can only be suggestive
Which treatment options for feline hyperthyroidism are reversible if hypothyroidism develops?
Medical (Methimazole) & dietary
If ectopic thyroid tissue is present, what would be your best treatment choice?
radioiodine
Regardless of therapy choice, ~25% of cats will develop what after being treated for hyperthyroidism? why?
25% develop azotemia
hyperthyroidism masks renal disease by increasing GFR–so when you stop the disease, GFR decreases and azotemia develops
Methimazole:
1) MOA
2) most common side effect
inhibits formations of T4
GI side effects most common (anorexia, vomiting)
What clinical side effects (4), if they develop, would mean permanent d/c of methimazole as a method of treatment?
1) severe facial pruritus
2) thrombocytopenia (bleeding)
3) icertus
4) agranulocytosis (low neutrophil #)
When regulating T4 levels in hyperthyroid cat, where do we want the levels to be?
in lower half of RR
You must give radioactive iodine ___months to work before assuming cat is still hyperthyroid or has developed hypothyroidism
3 months
*transient hypothyroidism is normal
When would surgery or radioactive iodine be contraindicated in treating feline hyperthyroidism?
If the cat is azotemic prior to receiving any treatment AND fails trial medical therapy
*failing= azotemia worsens and clinical signs of renal failure develop
The best marker of hypothyroidism in a cat?
Elevated TSH
When do clinical signs of DM develop?
when glucosuria develops
What is the renal threshold for glucose in
1) dogs
2) cats
1) 200mg/dL
2) 300mg/dL
How does sex predilection for DM differ btwn dogs and cats?
dogs–females are 2x as likely to be affected
cats–neutered males are more likely
3 most common clinical signs assoc. with DM?
polyphagia
PU/PD
weight loss
A clinical sign of DM unique to
1) dogs
2) cats
1) cataracts
2) diabetic neuropathy
What 3 criteria must be met to make the dx of DM?
1) appropriate clinical signs
2) persistent fasting hyperglycemia
3) persistent glucosuria
Why are UTIs so important to r/o before starting therapy for DM? How can we rule out a UTI in a diabetic?
only way to rule out is to do a culture
infection can cause insulin resistance!!
As far as dietary recommendations for diabetics go, the most important thing to avoid feeding is?
simple carbs–are absorbed too quickly and cause severe post-prandial hyperglycemia
Which types of insulin:
1) are veterinary products
2) are used for emergency situations
1) Vetsulin (lente) & PZI
2) Regular & Lispro
Considering handling of insulin, most should be ______ to be mixed; the exception is ?
rolled;
exception= vetsulin (shake this one)
Which insulin, due to higher potency, requires a lower initial dose?
Detemir
What 4 components do we use to monitor diabetics?
*4 pieces of the puzzle
1) clinical signs
2) BG curves
3) glycosylated proteins
4) urine glucose
What is the ideal nadir for both dogs and cats?
What do you do if it’s too high? Too low?
80-150
If too high–increase dose 10-25%
if too low–decrease dose (50% if clinical signs of hypoglycemia)
What are your two options if duration of insulin activity isn’t appropriate?
change insulin
change frequency of administration
Which oral hypoglycemic agent can replace insulin in cats? What’s its MOA?
Glipizide;
binds sulfonylurea receptor to cause insulin release
Which oral hypoglycemic agent can only be used IN COMBINATION with insulin (not alone) in both dogs and cats
Acarbose
**prevents breakdown of maltose and sucrose to decrease carb/glucose absorption from GI tract
What two situations (if present) should make you SUSPECT insulin resistance
1) if patient remains markedly hyperglycemic on dose >1.0 U/kg
2) if patient requires a dose >1.5U/kg to
If a dog is on a low dose of insulin but still becoming hypoglycemic, you should suspect?
maldigestion/malabsorption (EPI or other dz)
The predominant ketone in dogs and cats?
beta-hydroxybutyrate
also acetone and acetoacetic acid
When treating DKA, what are your top 3 goals?
1) achieve and maintain hydration
2) correct electrolyte abnormalities
3) reduce BG
A patient presents with DKA–when you spin the blood down, the serum is red. What is your ain concern?
Hypophosphatemia
**causes hemolysis
In DKA patients, by which route should you NOT administer insulin?
SQ–dehydration alters absorption
1 presenting clinical sign of dogs with insulinoma?
seizures
If BG is low (<60) what two insulin level findings would be indicative of insulinoma
1) if inuslin is above normal
2) if insulin in upper 50% of RR
Why is prednisone indicated for tx of insulinomas?
it causes insulin resistance
What are the chances of a cure with surgical removal in insulinoma?
0%!!
only diagnostic and therapeutic–WILL NOT CURE
Compared to feline thyroid tumors, canine thyroid tumors tend to be _____ and _______
malignant and non-functional
A dog presents for a cervical mass. When you got to aspirate it, the contents appears to be straight blood… you’re suspicious the mass is a?
thyroid tumor (most likely carcinoma)
What characteristics of mass must be present for sx to potentially be curative?
Mass must be small, freely movable
**if invasive, can’t cure with sx
Pheochromocytomas are tumors of the _____ and secrete what?
adrenal medulla
Epi and norepi
Prior to sx on adrenal glands, you can administer which drug? Why?
Phenoxybenzamine–blocks effects of any epi that gets released
Gastrinomas are tumors of the _____ cells; what do they secrete?
pancreatic delta cells
*secrete gastrin
2 effects of hypergastrinemia
1) increased gastric acid secretion (ulcerations)
2) hypertrophy of stomach rugal folds (can affect motility and cause outflow tract obstruction)
The biggest stimulus for secretion of ADH is?
plasma osmolality
Define polydipsia in:
1) dogs
2) cats
1) > 100ml/kg/day
2) >45ml/kg/day
3 most common causes of PU/PD in
1) dogs
2) cats
1) renal failure, HAC, DM
2) renal failure, DM, hyperthryoid
Only do a modified water deprivation test if what 3 things are left on your ddx list?
1) central DI
2) psychogenic polydipsia
3) primary nephrogenic DI
What are the 3 major endpoints for water deprivation test?
1) Azotemia (if present before test, don’t start it)
2) plasma osmolality >320 mOsm/kg
3) USG concentrates
(>1.030 dog, >1.035 cat)
Why might some animals with DI show neuro signs?
~40% have a tumor in area of pituitary destroying ability to secrete ADH
For which cause of PU/PD is water restriction the recommended tx?
Psychogenic polydipsia
What type of treatment is used for nephrogenic DI?
Thiazide diurectics
**dehydrates patient and forces them to save Na and water follows
