Endocrine Review Flashcards
(150 cards)
1
Q
Atypical Addison’s is where patients
A
lack glucocorticoids (electrolytes and aldosterone is normal)
2
Q
Whay might Addison’s resemble
A
AKI or AKI on CKD
GI foreign body
Pancreatitis
Acute gastroenteritis
3
Q
What breeds often get Addisons
A
Genetic: standard poodles, bearded collies, Portuguese water dogs, duck tolling retrievers
Predisposed: great dane, St. Bernard, westies, wheaten terriers, Leonbergers, rottweilers
4
Q
What might you see clinical in dogs with atypical Addisons
A
just signs associated with lack of cortisol
1) Lack of stress leukogram
2) Impaired erythropoiesis (non-reg)
3) Impaired GI integrity: GI ulcers, vomiting/diarrhea, painful stomach, GI blood loss (anemia), impareid cholestrol absorption
4) Impaired vascular reactivity: hypotension in the face of stress, shock, impaired perfusion, acidosis
5) Mild megaesophagus with possible aspiration pneumonia
5
Q
Why with Addisonian dogs do you typically see a lower Na:K ratio
A
1) Impaired sodium absorption
2) Impaired potassium excretion
6
Q
What baseline cortisol tells you the patient does not have Addisons
A
If baseline cortisol is greater than 2
7
Q
In workup for Addisons, you find a baseline cortisol of <2. What do you do next
A
Must do an ACTH STIM
1) At 0 hours, sample pre-cortisol
2) Give synthetic ACTH (cosyntropin) IV
3) At 1 hr: sample post cortisol
Expect: Pre-cortisol to be low, post-cortisol to be low
8
Q
What is an alarming Sodium: Potassium ratio
A
Na:K of >28:1 = not typical
<28:1 - consider typical Addison’s
<25:1- highly suspicious for typical Addisons
<21:1 - slam dunk for typical Addisons
9
Q
How do you treat patient in Addisonian crisis
A
1) Fluids *** - corrects hypovolemia, acidosis
2) Treat hyperkalemia: fluids, insulin+glucose, Ca2+ gluconate IV, IV barcarbonate, albuterol
3) Treat cortisol deficiency: dex-SP IV (0.5mg/kg pred equiv)
4) Treat GI signs: maropitant, ondansetron, omeprazol/pantoprazole
5) Treat hypoglycemia: dextrose
6) Treat anemia: blood transfusion if severe, but usually not needed
10
Q
How do you maintenance treat Addison’s
A
1) Prednisone: 0.1-0.2mg/kg
2) DOCP: 2.2mg/kg (Typical)
during stressfil event: increase pred 0.5mg/kg day before, decrease to physiologic dose 48hours after event
11
Q
What should you monitor longterm in Addison patients
A
PU/PD, polyphagia (decrease pred)
electrolytes: at 2 weeks post-dx tjen weekly until electrolytes begin to shift
dose reduce or lengthen treatment interval if ratio indicates
recheck q3-6 months after stable
12
Q
What are good screening tests for Cushings
A
1) UCC ratio
2) LDDS test
3) ACTH stim
13
Q
What are the Cushing discriminatory tests
A
1) UCC ratio
2) LDDS test (if suppression, escape)
3) HDDS (after LDDS or ACTH stim)
4) eACTH
5) Imaging: adrenals, brain
14
Q
How is a UCCR test performed for Cushing screening
A
Collect urine at home
Measure cortisol and creatinine
if normal then the ratio is not elevated
15
Q
How do you perform a LDDS test for cushings
A
Measure cortisol at 0h
Give 0.01 mg/kg dexSP IV
Measure 4 h cortisol
Measure 8 hour cortisol
Normally will have suppression at 8 hours
16
Q
How do you perform HDDS test for Cushings
A
Measure cortisol at 0h
Give 0.1 mg/kg dexSP IV
Measure 4 h cortisol
Measure 8 hour cortisol
Normally will have suppression at 8 hours
17
Q
What value of UCC would you expect with Cushings
A
elevated
18
Q
How do you distinguish AT from PDH when doinig LDDS test and HDDS
A
Adrenal tumors do not suppress
19
Q
Why might you do adrenalectomy for Cushings
A
50% benign, 50% malignant
-Vascular invasion possible (malignant)
-Must supplement prednisone post-sx
-No need to supplement mineralocorticoids
-Wean over 4-6 months
20
Q
How do you medically treat cushings
A
Trilostane: inhibits 3-b-hydroxysteroid dehydrogenase
Mitotane: destroys zona fasiculate
21
Q
What additional therapies of Cushings might be needed
A
-Treat proteinuria with ACE-inhibitors or ARBs
-Treat thrombotic disease via clopidogrel
-Treat hypertension: ACE-Inhibitors +/- amlodipine
-Monitor for and treat pyodermas and UTIs
-Dose adjust if clinical signs retunr
22
Q
What is the effect of exogenous steroids causing Cushings
A
Exogenous steroids causes decreased ACTH
leads to atrophy of adrenal glands (no cortisol)
23
Q
What are the effects of an adrenal tumor
A
Decreased ACTH secretion due to negative feedback
one adrenal gland has no production
other adrenal gland (with tumor) produces high amounts of cortisol
24
Q
What are the effects of having PDH
A
Increased ACTH secretion causing both adrenal glands to produce high amounts of cortisol
25
What causes primary hypothyroidism (acquired)
1) Lymphocytic thyroiditis
2) Follicular atrophy
26
What is the most common cause of low TT4
Euthyroid sick syndrome
-Concurrent illness
-Drugs (steroids, phenobarb, sulfonamides)
-Cushing's
27
Why must you also have TSH measurement
To distinguish true hypothyroidism from euthyroid sick syndrome
28
Low TT4
High T4
Primary Hypothyroidism
29
Low TT4
Low TSH
Euthyroid Sick Syndrome
30
Low TT4
Normal TSH
Inconclusive
Add fT4 measurement for further workup
If low fT4 then primary hypothyroidism
If normal then euthyroid sick syndrome
31
What are specific clinical signs of primary hypothyroidism (congenital)
Disproportionate dwarfism
Broad skull, short mandible
Delayed epiphyseal growth
32
How do you treat hypthyroidism
Levothyroxine
0.02mg/kg BID initially can decrease to q24h when controlled or 0.02-0.04 mg/kg once daily
33
What is the clinical response after treatment of hypothyroidism with levothyroxine *
activity level: about 2 weeks
haircoat, weight, bloodwork: 6-8 weeks
neurologic signs: months
34
T/F: hypothyroid dogs have PU/PD
False
35
What are the clinical signs of hypthyroidism
-Weight gain with normal/decreased appetite
-Dull mentation/lethargy
-Derm: alopecia, seborrhea, hyperkeratosis, pyoderma
-Neuromuscular reflex disorders (e.g facial paresis/paralysis)
-NO PU/PD
-Hypercholesterolemia
+/- mild bradycardia
+/- mild, Non-reg anemia
36
What are unlikely correlations of hypothyroidism
Megaesophagus
Laryngeal paralysis
vWF deficiency
37
How do you monitor hypothyroidism treatment
Test TT4 at 6 hours post pill
TT4 should be high-normal/slightly elevated and no clinical signs of hyperthyroidism
38
What might cause primary hyperthyroidism
1) Benign thyroid adenomas (98%) - 70% have bilateral disease
2) Thyroid carcinoma (2%)
39
What are the clinical signs of hyperthyroidism
1) Weight loss with polyphagia
2) PU/PD
3) Increased activity, restlessness, irritability
4) Vomiting
5) Thyroid goiter
6) Unkmept haircoat
7) Tachycardia +/- gallop rhythm
+/- hypertension
+/- systolic murmur
+/- retinal petechiation
+/- small, irregular kidney if concurrent renal disease
40
What labwork changes will you see in a cat with hyperthyroidism
Increased PCV, USG, glucose, BUN, ALT +/- AL_
41
What is a good screening method for hyperthyroidism
high TT4
if normal, but hyperT4 suspected then test fT4. if High then it will be hyperthyroidism
42
TT4 has high specificity or sensitivity
fT4 has high specificity or sensitivity
TT4= high specificity
fT4: high sensitivity
43
Aside from TT4 and fT4, what other diagnostic can you do for hyperthyroidism
Nuclear scintigraphy (Technesium-99): adenomas brighter than salivary glands
44
How might you treat hyperthyroidism
1) Hills y/d: low iodine
2) Methimazole (oral, transdermal) to block thyroid synthesis
3) I-131
4) Surgery
45
What might tell you to stop treatment of Methimazole
Facial excoriations
Hepatopathy
Blood dyscrasias
46
What does I-131 do
destroys the hyperactive cells (normal cells have atrophied due to low TSH) afterwards the normal cells can grow under the influence of TSH
47
Pros and cons of I-131
Pros: permanent, spares healthy cells, no pilling
Cons: expensive, special facilties, isolation period, waste dispoval, irreversible, possilbe iatrogenic hypoT4 and need to pill levothyroxine
might need >1 treatment
48
What are pros and cons of surgery for hyperthyroidism
Pros: permanent
Cons: removes healthy thyroid cells, may remove parathyroids leading to hypocalcemia, laryngeal paralysis, expensive
49
What should you monitor during or after hyperthroidism treatment
Total T4 and TSH
Renal parameters (BUN, Creatinine, K+, P), USG, blood pressure
Avoid: hypothyroidism and hypothyroidism with azotemia
50
What is the pathophysiology of diabetes mellitus
1) Hyperglycemia (no cellular glucose uptake)
2) Hyperlipidemia
3) Ketones
4) Hypertriglyceridemia
5) Hypercholesterolemia
6) PU/PD
51
What diabetic types do dogs vs cats typically get
Dog: lack of insulin (type I)
Cat: insulin resistance (type 2)
52
T/F: cats with diabetes get cataracts
False- no cataracts
53
What is a species specific sign of diabetes mellitus in dogs
Cataracts
54
What is the renal glucose threshold of dogs
180 mg/dL
55
What is the renal glucose threshold of cats
250 mg/dL
56
What specific clinical signs is seen in cats with diabetes mellitus
Frosy paws
Neuropathies
57
What is recommended diet for dog with diabetes
Complex carbs
58
What is recommended diet for cat with diabetes
High protein
Avoid carbs
59
What is Bexagliflozin (Bexacat) and Velagliflozin (Senvelgo) used for
Cats- once daily treatments for diabetes
SGLT-2 inhibitors - must monitor ketones because they can develop euglycemic DKA
60
Why do you need to monitor cats on SGLT-2 inhibitors like Bexagliflozin and Velaglifozin
must monitor ketones because they can develop euglycemic DKA
61
Short acting insulin used for DKA
Regular
62
What are the methods of insulin resistance and counter-reglatory hormones ***
1) Cortisol: infections, concurrent illnesses, exogenous steroids, Cushings
2) Catecholamines: infections, concurrent illness
3) Thyroid hormone: hypothyroidism, hyperthyroidism
4) Progesterone: pregnancy, diestrus
5) Growth hormone: acromegaly
6) Glucagon: rare tumors
63
What diet is recommended in dogs and cats with diabetes
meal-feeding is best
avoid simple sugars in both
Cats: higher protein
Dogs: complex carbs
64
assesses hyperglycemia over the previous 2 weeks
Fructosamine (glycosylated albumin)
65
When monitoring diabetes, what should the urine dipstick look like
trace glucose and no ketones
66
What are the clinical signs of DKA
lethargy, anorexia, vomiting, shock, previous history of PU/PD, polyphagia +/- weight loss
67
How do you treat DKA
Must have 24hour facility
1) Fluids- dont drop glucose more than 100mg/dL per hour or cerebral edema
2) Address electrolyte abnormaltieis
-Hypokalemia (weakness), hypophosphatemia (hemolysis)
3) Regular insulin IV or IM after patient rehydrated and electrolytes addressed
4) Address acid-base status
5) Address nausea and vomiting
6) Monitor frequently
68
What is first step of DKA management
Fluids!
69
When insulin reaches what dose, what are you suspicious of insulin resistance
5 Units
70
Why might an animal be having no response to insulin
1) Improper technique
2) Expired insulin
3) Incorrect syringe
4) Improper storage
71
How do you test for acromegaly
test IG-F1
72
What is the normal dose of insulin
0.25-1.5 units/kg
73
Somogyi effect
rapid drop below 60mg/dL over a short amount of time (1-2h) is occurring after giving the insulin
stress release of glucagon, epinephrine results in the hyperglycemia that can stay elevated for long amounts of time
74
Why does insulin need to be given IV in DKA patients
they are typically dehydrated and decreased absorption
75
What might you see with hypokalemia
neck ventroflexion
weakness
76
Why is CKD, Cushings, HypoT4, and diabetes not an appropriate differential for an Addisonian crisis
CKD- not acute, but azotemia and low USG
Cushings: PU/PD but no azotemia and not sick
HypoT4: lethargic but no azotemia, no PU/PD, not sick
Diabetes: PU/PD but not sick
Maybe DKA: PU/PD, azotemia, low USG, acute onset
77
What values on biochemistry will be elevated in Addisons
Lack of glucocorticoids:
Hypoglycemia
Hypoalbuminemia
Hypocholoesterolemia
Anemia (NR)
Lack of mineralcal:
Hyponatremia
Hyperkalemia
Azotemia
Hyperphosphatemia
78
If baseline cortisol in >2 then you can _______ Addisons. If it is <2 then you can ________
>2 = rule out Addisons
<2 = do ACTH stim for confirmation
79
After I-131, how long are cats typically hypothyroid
2weeks to 6 months; monitor the T4 and TSH
80
What is the main liver enzyme that is elevated in cats with hyperthyroidism
ALT
81
When treating hyperthyroid you should first start with
A reversible treatment when possible
Methimazole - euthyroid in 10-14 days
82
What are the consequences of methimazole
Facial excorations
Blood dyscrasias
Hepatopathy
GI signs
83
Consequences of T4 reduction in cats
Unmasked CKD
Hypothyroidism
84
The post levothyroxine levels for hypothyroidism treatment should be
high normal or slightly elevated
85
What is your top differential for a cat with PU/PD, polyphagia, and weight loss
hyperthyroidism or diabetes
86
What causes diabetes mellitus in dogs
Beta cell destruction via
1) Immune mediated
2) Vacuolar degeneration
3) Pancreatitis
87
What causes diabetes mellitus in cats
1) Beta cell dysfunction (insulin resistance)
2) Beta celll loss
-Amyloid deposition
-Pancreatitis
88
Diagnosis of diabetes mellitus only needs what two steps
Urine dipstick: glucosuria
Hyperglycemia: hyperglycemia
If its a cat, may need to confirm with fructosamine
89
What are the clin path abnormalities of diabetes mellitus
Increased glucose, ALP, cholesterol, glucosuria
90
What insulin syringes should you use in cats
U-100
91
What is the initial treatment plan for cats with diabetes mellitus
Insulin BID (starting dose is 1-2 U/dose)
-Do not exceed 2 units as initial dose
-Roll to mix
Diet: Protein >40% ME, Low carbohydrate, canned preferred
92
Studies show greater remission rate in cats receiving glargine, what other insulin options are there for cats
-PZI (Prozinc)
-Detemir (Levemir)
or SLTG-2 inhibitors
93
What are the types of SGLT-2 inhibitors
Bexagliflozin
Velagliflozin
94
Why do you need to choose SGLT-2 patients carefully
Need to ensure
1) Newly diagnosed diabetic cat
2) No concurrent illness
3) No active pancreatitis
4) No urine ketones
5) No severe renal disease
6) No hepatic disease
WARNING: euglycemic DKA
95
What is the typical initial treatment for dogs with diabetes mellitus
Insulin: 0.25-0.5 U/kg starting, U-40 syringes
shake to mix
-Vetsulin or NPH or Detemir
Diet: high fiber (soluble and insoluble)
96
What insulin syringe needles are used for dogs
U-40
97
Cats use _____syringes, dogs use ______ syrings
Cats: U-100
Dogs: U-40
98
How does the insulin starting dose differ between dogs and cats
Dogs: 0.25-0.5 U/kg starting
Cats: 1-2 U/dose starting
99
T/F: syringe type must match insulin time
True
If you use U-100 syringe with U-40 insulin then you are under dosing
If you use U-40 syringe with U-100 insulin then you are overdosing the patient
100
After diabetes mellitus dx, when should you recheck
first recheck at 7-14 days
-prior to morning dose
-observe insulin technique
Diagnostics
1) Spot glucose
2) Urine dipstick
+/- fructosamine or blood glucose curve
101
How do you get a blood glucose curve
obtain blood sample every 2 hours (with glargine every 3-4 hours)
if glucose <150mg/dl, obtain sample every hour
102
What are the ideal blood glucose curve values for a cat
Ideal max: 300mg/dl
Ideal range: 80-300mg/dl
Ideal nadir: 80-150mg/dl
103
What are the ideal blood glucose curve values for a dog
Ideal max: 200mg/dl
Ideal range: 80-200mg/dl
Ideal nadir: 80-150mg/dl
104
What at home monitoring can you do for diabetes mellitus
Alpha trak for cats and dogs ear sampe q2-4hr for 12 hours
or continuous monitoring up to 2 weeks
urine sticks: should always have trace or 1+ glucose
105
Managed diabetic patients should trace or 1+ glucose on urine dipstick
What might no glucosuria mean
overdose (dogs/cats) and/or remission (cats)
106
T/F: Managed diabetic patients should not have ketones
True
107
What should you do when you see a blood glucose curve that remains high through sampling
1) Perform 12-24 hr BGC at home
and/or
2) Explore owner/insulin issue
and/or
3) Recommend diagnostics for concurrent illness (insulin resistance)
108
BGC of dog: begins at 200 mg/dl but drops to 80mg/dl and remains stable until 12 hours
What do you do?
Nothing ! - no change
109
BGC of dog: Drops to 50mg/dL at 5 hours then increased to 350mg/dL at 9 hours
What do you do?
Change to less potent insulin
or
consider Somogyi
110
What amount determines insulin resistance in dog **
Uncontrolled DM when receiving > or equal 1.5 units/kg/dose
111
What amount determines insulin resistance in cats
Uncontrolled DM when receiving > or equal to 5 units/dose
112
What do you consider when diabetes is controlled and then suddenly isnt
insulin resistance
113
T/F: insulin resistance can happen at any dose
True
114
How do you test potential owner or insulin issues
TESST
T- improper technique?
E- Expired insulin?
S- Incorrect syringe?
St- Improper storage?
for previously controlled diabetic or never well-controlled diabetic
115
What are the counterregulatory homrones for insulin resistance **
1) Cortisol: infections, concurrent illnesses, exogenous steroids, Cushings
2) Catecholamines: infections, concurrent illness
3) Thyroid hormone: hypothyroidism, hyperthyroidism
4) Progesterone: pregnancy, diestrus
5) Growth hormone: acromegaly
6) Glucagon: rare tumors
116
What might be the cause of insulin resistance in a cat with large face and paws, prognathism, enlarged space between eyes, cardiac murmur, enlarged abdomen
Acromegaly
Diagnosis via IGF-1 levels, CT scans
117
How do you diagnose Acromegaly
IGF-1 levels, CT scans
118
What are the clinical signs of hypothyroidism
Metabolic signs: lethargy, weight gain, exercise intolerance, cold intolerance
Dermatologic: hypotrichosis, alopecia, dry quality coat, pyoderma, hyperpigmentation, seborrhea
Other: decreased libido, facial nerve paralysis, laryngeal paralysis, megaesophagus, KCS, bradycardia
119
What is a major laboratory abnormalities of hypothyroidism
Hypercholesterolemia and may be accompanied with hypertriglyceridemia
120
Dont test a dog for hypothyroidism if
No clinical signs
If patient is sick
Dont interpret a low total T4 alone
121
How should you test hypothyroidism in dogs
Do perform both TT4 +/- fT4 and TSH
122
What causes low T4 in dogs
1) Primary hypothyroidism:
-lymphocytic thyroiditis against thyroglobulin
-Idiopathic atrophy
2) Euthyroid sick syndrome
Suppression of T4 by other conditions like concurrent illness, medications (steroids, phenobarb) or Cushings
123
Low T4
Low fT4
High TSH
Primary hypothyroidism:
-lymphocytic thyroiditis against thyroglobulin
-Idiopathic atrophy
25% of hypothyroid patients have a normal TSH
124
Low T4
Normal fT4
Normal to Low TSH
Euthyroid sick syndrome
Suppression of T4 by other conditions like concurrent illness, medications (steroids, phenobarb) or Cushings
125
What therapy do you give for hypothyroidism
L-thyroxine at 0.02mg/kg BID
do not exceed 0.8mg per dose
some dogs can be maintained at once daily dosing
126
How. do you monitor treatment response to L-thyroxine
After 6-8 weeks of thrapy
Measure T4 at 4-6 hours post-pill sample
Maintain in high normal or slightly high range
127
severe, life-threatening disease where patient has puffy face, paresis/paralysis/obtunded, bradycardia, hypothermia
low sodium and hypercholesterolemnia
rare
Myxedema coma
-Levothyroxine IV - do careful correction of hyponatremia
128
What will you see on labwork with hyperthyroidism
Increased ALT and/or ALP
+/- Increased BUN
Minimally-concentrated urine
129
Is Total T4 more specific or sensitive than FT4
TT4 is more specific (more false negatives)
fT4 is more sensitive (more false positives)
130
What is the gold standard of diagnosing hyperthyroidism
Nuclear scintigraphy = gold standard
brighter than salivary glands
131
How long does a restricted iodine diet take to normalize T4 levels
3 weeks to 6 months
132
What is a downside of doing restricted iodine diet
-Minimum weight gain
-Incomplete resolution of clinical signs
-No significant creatinine increase
-No significant ALT decrease
133
What is the mechanism of methimazole
Inhibits thyroid peroxidase which iodinates T3 and T4
134
Stop methimazole treatment if
1) CBC abnormalities (thrombocytopenia, anemia, neutropenia)
2) Liver enzyme elevations
3) Facial excoriations
135
After I-131 treatment how often should you test them
30,60,90, 180 days after treatment
1) Thyroid panel (total T4, eTSH)
2) Renal values (BUN, creatinine, electrolytes, USG)
3) Blood pressure with fundic exam
136
What is a sensitive and specific test in detecting hypothyroidism in azotemic cats
TSH
137
Aldosterone functions to
Retain sodium and chloride
Excretes potassium
138
What parts of the adrenal gland are impacted by Addison's disease
Typical: both glomerulosa and fasciculata (both cortisol and aldosterone)
Atypical: just fasciculata (only cortisol affected)
139
What is the typical signalment of dogs with Addisons
young to middle aged dogs
usually female
140
What clinical signs are attributable to lost of aldosterone
polyuria/ polydipsia
shock due to hypovolemmia and hypotension
bradycardia despite hypotension
141
What EKG characteristics is seen with Addisons
No P-wave
Spiked T-wave (can be inverted)
Wide QRS complex
142
What CBC changes are seen with loss of cortisol
-Lack of stress leukogram
-Anemia (GI blood loss, decreased erythropoesis)
143
What tests can you do for Addisons
1) Sodium: potassium ratio
2) ACTH stim: low pre and post, eACTH is high
3) Baseline cortisol: only rules out Addisons
144
What should you do for emergency treatment of Addisons
1) Treat shock: fluids
2) Replace glucocorticoids: dexamethasone only
3) Correct hyperkalemia: fluids, insulin +dextrose or just dextrose, calcium gluconate
145
What should you consider when treating Addisons with Fludrocortisone
1) 50% do not need prednisone, start all on prednisone
2) Discontinue if PU/PD/polyphagia is severe
146
What should you consider when treating Addisons with DOCP
it is a subcutaneous injection
but all patients on DOCP require prednisone
147
How do you treat typical and atypical Addisons
Physiologic prednisone 0.25mg/kg
148
ACTH stim is only used for
Iatrogenic Cushings
Monitoring Cushing's treatment
Addisons
149
Only test for iatrogenic cushings
ACTH stimulation
150
What is given for ACTH stim
cosyntropin IV
