Endocrine Flashcards
How is the corticotropin releasing hormone test (CRHT) performed?
Basal ACTH –> give ovine corticotropin releasing factor –> measure ACTH again 30 min later
JVIM 2021, Tanaka et al
Is the corticotropin releasing hormone test (CRTH) useful to diagnose Cushing’s, differentiate PDHAC vs ADHAC, or both?
Too much overlap ADHAC vs controls for de novo diagnosis. May be useful to differentiate pituitary vs adrenal dependent if already diagnosed with Cushing’s.
JVIM 2021, Tanaka et al
What would the expected post corticotropin releasing hormone test (CRTH) ACTH result be for PDHAC vs ADHAC? (ie, high, low, or the same compared with healthy dogs)
PDHAC – higher
ADHAC – no difference
JVIM 2021, Tanaka et al
Where is ACTH produced in primary bilateral adrenocortical hyperplasia, macro or micronodular (PBMAH)?
ACTH is made in the adrenal. Acts as paracrine rather than endocrine. PBMAH is rare in dogs.
JVIM 2021, Arias et al
Which of the following will be HIGHER in dogs with untreated HAC and why (if known)?
Phos
tCa, iCa
Urinary Ca excretion
PTH
25-(OH)D
Calcitriol
FGF-23
Phos - decr urinary excretion
PTH (adrenal secondary hyper-PTH):
–Multifactorial
–Direct and indirect cortisol effects
–Incr urinary Ca excretion + Phos retention
Urinary Ca excretion – who knows why
JVIM 2021, Corsini et al
Which of the following will be LOWER in dogs with untreated HAC and why (if known)?
Phos
tCa, iCa
Urinary Ca excretion
PTH
25-(OH)D
Calcitriol
FGF-23
25-(OH)D
FGF-23
Who knows why for either one
JVIM 2021, Corsini et al
Which of the following have NO DIFFERENCE in dogs with untreated HAC vs normal dogs?
Phos
tCa, iCa
Urinary Ca excretion
PTH
25-(OH)D
Calcitriol
FGF-23
tCa, iCa
Calcitriol
JVIM 2021, Corsini et al
Which of the following were able to differentiate good vs undercontrolled HAC dogs treated with trilostane?
Endogenous ACTH
Pre-pill cortisol/endogenous ACTH ratio
ACTH Stim
ALT
GGT
Haptoglobin
UCCR
USG
Haptoglobin (best predictor), ALT, GGT. BUT all had overlap between the two groups.
JVIM 2021, Golinelli et al
How does trilostane work and which hormonal endproducts are suppressed?
Competitive inhibitor of 3-beta-hydroxysteroid dehydrogenase –> decr cortisol, aldosterone, testosterone
JVIM 2021, Golinelli et al
What percentage of dogs develop hypernatremia post hypophysectomy? Are there any predisposing factors and does this affect outcome?
46%, no, no
JVIM 2021, Magno et al
What percentage of dogs have central DI >2 weeks post hypophysectomy? Are there predisposing factors?
71%, pituitary macroadenoma
JVIM 2021, Magno et al
What is the effect of hypophysectomy on potassium?
Mild transient increase, but never above reference interval.
JVIM 2021, Magno et al
Fill in the blanks:
A study comparing standard DOCP dose (___ mg/kg) vs low dose (____ mg/kg) q30d found the latter was just as effective and had fewer overtreated dogs.
2.2mg/kg vs 1.1mg/kg q30d
JVIM 2021, Vincent et al
True or false:
If the Na/K is still mild to moderately low after the first DOCP, the dose should be increased for next time.
False – Na/K is higher after 2nd and 3rd doses even when same amount is given, suggesting an initial acclimation period.
JVIM 2021, Vincent et al
How does PCV affect glucometer readings? Does it affect FSL readings?
Glucometer: lower PCV –> more plasma and glu to interact with –> spuriously higher BG
FSL: higher PCV –> higher IG (unknown why)
JVIM 2021, Howard et al
JVIM 2021, Shea et al
For which BGs is FSL less accurate: very high, normal, very low
Very high and very low
JVIM 2021, Shea et al
Do DM dogs tend to have nocturnal HYPER or HYPOglycemia?
HYPERglycemia
JVIM 2021, Shea et al
What two diet strategies may mitigate postprandial hyperglycemia?
High fiber
Low digestible carb
JVIM 2021, Shea et al
Which insulin has lower day to day variability? Which had better overall glycemic control?
Human recombinant insulin (Toujeo, insulin degludec)
Porcine lente insulin
Lower day to day variability - human recombinant
Better overall glycemic control - porcine lente
JVIM 2021, Miller et al
Compare the accuracy of insulin pens vs syringes.
Pens are more accurate. Similar precision pens vs syringes.
JVIM 2021, Malerba et al
Which are most reliable for insulin doses <2U, pens or syringes?
Pens
JVIM 2021, Malerba et al
True or false:
DM dogs tend to have lower TLI, and this correlates with time since DM diagnosis.
False – no difference in TLI in DM vs normal dogs, no correlation with time since dx.
JVIM 2021, Hamilton et al
True or False:
DM dogs frequently have elevated PSL or TLI suggestive of pancreatitis, without any additional supporting evidence.
True. HAC dogs also do this. Some of the DM dogs in the study may have had undiagnosed HAC.
JVIM 2021, Hamilton et al
Name at least 4 patient risk factors for iatrogenic hypothyroidism with I-131, and at least one for persistent hyperthyroidism.
Hypo-T:
–detectable TSH (OR 12)
–higher 24hr % I-131 uptake (OR 3.7)
–female (OR 2.4)
–bilateral thyroid disease esp with homogenous uptake (OR 3.7)
–Older
–Milder severity score
Hyper-T:
–Younger
–Higher severity score (OR 1.9)
–Lower 24hr % I-131 uptake (OR 3.5)
JVIM 2021, Peterson
Which thyroid hormone abnormality becomes more prominent as hyperthyroidism progresses? T4, T3, or TSH
T3
JVIM 2021, Peterson
What proportion of cats are azotemic post I-131 in the following categories: persistent hyper-T, euthyroid, subclinical hypo-T, overt hypo-T
Persistent hyper-T: 0.4%
Euthyroid: 12%
Subclinical hypo-T: 39%
Overt hypo-T: 70%
JVIM 2021, Peterson
In Europe, cats are often hospitalized 2-3 weeks post I-131. Two thirds of cats with T4 elevated at discharge BUT <____ will become euthyroid over time, but if >____ euthyroidism is unlikely.
<7.7, >11.6
JVIM 2021, Mullowney
True or false regarding I-131 treatment failure:
Re-treatment with I-131 and thyroidectomy have similar success rates.
False – re-treatment with I-131 was successful in all cats (incl 2 with carcinoma), thyroidectomy successful in only 1/3 of cats (half had carcinoma).
JVIM 2021, Mullowney
How does oral vs SQ radioactive iodine affect uptake?
Generally similar uptake (but small study – N=7) – 1 cat had 2-fold difference
JVIM 2021, Cosford
In one small study, 64% of patients received more or less I-131 than the prescribed dose?
> 10% less than the prescribed dose – time in syringe, residual left in syringe, syringe material, other
JVIM 2021, Busser
True or false:
Hyperthyroid cats frequently have markers of hypercoagulability, esp if concurrent heart disease.
False – hyperthyroid cats have some altered markers of hemostasis (ex: incr fibrinogen, AT activity, vWB:Ag) which improve post I-131, but did not fulfill criteria for hypercoagulability. Values did not correlate with cardiomyopathy.
JVIM 2021, Keebaugh
How are insulin, GH, IGF-1, and liver related?
Insulin –> incr liver GH receptors –> GH tells liver to make IGF-1 –> neg feedback on GH
JVIM 2021, Zini
Serum IGF-1 is a surrogate for measuring what value?
Represents the previous 24hrs of GH activity
JVIM 2021, Zini
How does overall body weight, weight gain and weight loss affect IGF-1 in cats?
No effect (but small study - N=10 cats)
JVIM 2021, Zini
What is the prevalence of hypersomatotropism (HST) in DM cats?
18-32%
JVIM 2021, Bokhorst
What threshold of IGF-1 is consistent with hypersomatotropism (HST)? Does a normal value rule it out?
IGF-1 >1000 –> HST
Can fluctuate; one normal value does not rule out
JVIM 2021, Bokhorst
Is hypersomatotropism (HST) most frequently caused by pituitary adenoma, adenocarcinoma, or hyperplasia?
Adenoma
JVIM 2021, Bokhorst
What is the cutoff P/B for pituitary enlargement in dogs vs cats?
Cats: >0.40
Dogs: >0.31
JVIM 2021, Bokhorst
What is the most common signalment (breed, sex, age) of cats diagnosed with hypersomatotropism?
DSH (69%), MN (78%), avg 10yrs
JVIM 2021, Bokhorst
JVIM 2021, Fenn
How do the following treatments compare in inducing DM remission in cats with hypersomatotropism? (proportion of cats, how long it takes, durability of remission)
Surgery
Stereotactic radiation
Pasireotide (what is this?)
Surgery: 70-92%, most within 7-10d, 12% relapse
Stereotactic radiation: ~1/3, 4mo, >1/3 relapse
Pasireotide (somatostatin analog): ~1/3 remission, took months, generally durable
JVIM 2021, Bokhorst
JVIM 2021, Fenn
Is IGF-1 helpful to monitor post hypophysectomy for treatment of hypersomatotropism (HST)?
Yes – 80% of cats normalized within 1mo. Cats without DM remission and no improvement in glycemic control maintained high IGF-1 –> tx failure.
JVIM 2021, Fenn
What three supplements do animals need post hypophysectomy?
DDAVP – usually temporary
Corticosteroid
Levothyroxine
JVIM 2021, Fenn
Are neuro deficits post hypophysectomy in cats typically permanent or temporary?
Temporary
JVIM 2021, Fenn
What is the perioperative death rate (within 2mo) for hypersomatotropic cats treated with hypophysectomy?
What are two important causes?
12-15%
Rebound hypoglycemia, bacterial meningitis/sepsis
JVIM 2021, Bokhorst
JVIM 2021, Fenn
What is the threshold for aldosterone to diagnose primary hyperaldosteronism (PHA) due to a functional adrenal tumor?
Ald >1000
JVIM 2021, Langlois
_________ and __________ are also significantly elevated in > ___ % of cats with aldosterone >3000.
Progesterone, corticosterone, >30%
JVIM 2021, Langlois
What are some potential consequences of hyperprogesteronism? (Physically, biochemically)
Most/all cats had DM, skin issues
20% potbellied
Some have low baseline or ACTH stim cortisol, and/or contralateral adrenal atrophy –> evidence of HPA axis suppression
JVIM 2021, Langlois
JVIM 2021, Harro
A cat with historic DM has recently become dysregulated and you diagnose it with an adrenal tumor. What are the most likely hormones the tumor is producing?
Aldosterone, progesterone, corticosterone
JVIM 2021, Langlois
JVIM 2021, Harro
True or False:
The fludrocortisone suppression test is a more sensitive indicator for primary hyperaldosteronism in cats compared with baseline aldosterone.
False – baseline aldosterone works fine
JVIM 2021, Harro
True or false:
An elevated SDMA is specific for CKD in cats undergoing I-131.
False – very hit and miss
JVIM 2020, Yu
In a study using TSH stimulation test to better identify hypothyroid cats, were the following most commonly high/low/normal in hypothyroid cats, and in what proportion of them?
–T4
–FT4
–TSH
–T4 normal 81%
–FT4 low, TSH high 85%
JVIM 2020, Wakeling
Can the following differentiate a truly hypothyroid cat vs (noncritical) extrathyroidal illness?
–Baseline T4, TSH
–TSH stimulation test
–Baseline T4, TSH: sort of; TSH can be mildly elevated in extrathyroidal illness, but rare and not usually to the degree typically seen with true hyperthyroidism
–TSH stimulation test: yes
JVIM 2020, Peterson
JVIM 2020, Wakeling
True or false:
Hypothyroidism can lead to systemic hypertension in cats.
True – seen in 23% of initially normotensive hyperthyroid cats that are then treated
JVIM 2020, Wakeling
In cats with nonthyroidal illness:
–Which thyroid hormone is most predictive of 30 day survival? (T4, FT4, TSH, T3)
–Do thyroid hormones scale with disease severity, type of disease, both, or neither?
–T4 > TSH (usually normal unless severely ill) > others
–Disease severity
JVIM 2020, Peterson
True or False:
Looking at Freestyle curves at home vs in hospital, insulin recommendation was higher for ~50% of cases looking at just the hospital curve.
True
JVIM 2020, Del Baldo
Posthypoglycemic hyperglycemia is (more, less, similarly) prevalent in DM cats with vs without good metabolic control.
Seen in 6% with good metabolic control, 70% with poor metabolic control
JVIM 2020, Kramer
Regarding exenatide extended release (EER), a glucagon-like peptide-1 (GLP-1) analog:
–What is the net effect and goal of the drug?
–What is its effect on:
–Glycemic variability (No gold standard way to measure GV, but what is the most common way?)
–Risk of hypoglycemic events
–Likelihood of DM remission
–Net effect: incr insulin to avoid postprandial hyperglycemia
–Improved GV compared with placebo. Can calculate GV by measuring the SD around the mean BG.
–No incr risk of hypoglycemia – EER does not stiulate insulin secretion once euglycemic, AND glucagon suppression is glucose dependent.
–Slightly higher chance of DM remission (but in humans, need to stay on EER to maintain remission)
JVIM 2020, Kramer
Regarding RBC oxidative stress:
–Is it higher, lower, or not affected by DM? How does DM tx and/or remission affect this?
–Is it higher, lower, or not affected by transient hyperglycemia? Hyperlipidemia?
–Higher oxidative stress in DM, minimal improvement with tx and remission
–Not affected by transient hyperglycemia and hyperlipidemia.
JVIM 2020, Zini
Describe the relationship between GH, IGF-1, and insulin.
–GH (from pituitary) causes liver to make IGF-1. Thus, serum IGF-1 reflects the previous 24hrs of GH activity.
–Insulin –> incr liver GH receptors –> incr sensitivity to GH –> incr IGF-1. So, treating DM with insulin can increase IGF-1 level.
JVIM 2021, Zini
How to pancreatic beta cells secrete insulin? Which portion of the pathway can be targeted to increase or decrease insulin secretion, and by which two drugs?
Glu enters beta cell through GLUT2 –> make ATP –> close K+ channel –> cell depolarization –> voltage gated Ca2+ channel opens –> Ca2+ flows in –> exocytosis of insulin
Can target K+ channel
–Glipizide keeps it CLOSED –> more insulin
–Diazoxide keeps it OPEN –> no insulin
JVIM 2020, Cook
Give at least four differentials for hyperinsulinemic hypoglycemia.
–Insulinoma
–Bartonella
–Babesia
–GH deficiency (can screen for with IGF-1)
–Glycogen storage disease type I or III
–Hyperketotic hypogycemia
–Congenital hyperinsulinism
JVIM 2020, Cook
There was a recent case report on congenital hyperinsulinism in a Shiba Inu. In people with this condition:
–When is surgery an option?
–If a genetic mutation is identified, how does this affect the chance for diazoxide response and remission?
–Sx is an option for focal disease (but workup is very difficult)
–Genetic mutation found –> less likely to respond to diazoxide, less likely to spontaneously resolve over time
JVIM 2020, Cook
A recent study developed a prediction tool for HAC.
–It used signalment, clinical signs, and which two biochemical parameters?
–How can this be used to aid in the HAC diagnosis? (Name two ways)
–ALP, USG
–Can use the tool to decide who to test (LDDST, ACTH Stim) and to determine how to interpret the test if consistent with HAC (if low score using the tool, PPV of the test is low – may be a false positive).
JVIM 2020, Schofield
In a study looking at various methods to discriminate adequate (A) vs underdosed (U) dogs on trilostane:
–Was any measured parameter (USG, ACTH stim, UCCR) sensitive and/or specific for either state?
–For serial cortisol measurements 30min prepill to 12hr post pill:
–Which was higher: 30 min prepill or 30 min post pill?
–When did trilostane typically start working, peak, wane, and stop?
–Any difference in trends between A vs U dogs?
–USG >1.020 was sens but not spec for A dogs (false positives). UCCR >130 was spec but not sens for U dogs (false negs).
Serum cortisol:
–Higher 30min post pill
–Trilostane starts 1hr, peak 2-3hrs, wane 4hrs, gone 6-8hrs
–U dogs had more sudden onset and dissipation – may benefit from TID dosing
JVIM 2020, Bermejo
What proportion of HAC dogs have BP >150 and >180 at the time of diagnosis? After 1 yr of tx with trilostane and antihypertensive meds?
Pre tx: BP >150 82%, >180 41%
1yr: >150 45%, >180 10%
JVIM 2020, San Jose
Which five of the following parameters affected risk of hypertension in HAC dogs, and at least one basic mechanism for three of them?
–ADHAC vs PDHAC
–Signalment, BCS
–Duration of HAC signs
–Clinical HAC control
–CBC changes
–Lytes at diagnosis vs during tx
–USG
–UPC
–Resting cortisol level at diagnosis vs during tx
–ACTH Stim
Thrombocytosis (marker, not cause of SHT)
–Cortisol causes incr plt via 1) incr EPO and 2) oxidative stress –> TXA2
–Both EPO and TXA2 are vasoconstrictors
Lower K+ (at dx): cortisol overwhelms 11β-hydroxysteroid dehydrogenase –> not converted to cortisone –> able to have mineralocorticoid effect
Proteinuria: incr glomerular pressure, glomerulosclerosis, dyslipidemia, endothelial dysfunction, hypercoagulability
Older –> higher BP
Higher resting cortisol (during tx, not at dx) –> higher BP
**ADHAC tended to run higher but did not reach statistical significance (possible type II error)
The other factors did not affect risk of SHT. Even when HAC control was improved, unable to deescalate hypertensive drugs.
JVIM 2020, San Jose
True or False:
Stress from the hospital visit is one differential for elevated UPC.
False – UCCR higher when urine collected in hospital vs at home, but no significant increase in UPC. Ultimately, just be consistent with how you submit UPCs (at home vs in hosp, pooled vs single).
JVIM 2020, Citron
For a study in dogs with chronic GI signs evaluated at a referral center:
–What percentage have baseline cortisol <2.0?
–What percentage have Addison’s? Typical vs atypical? Prevalence of GI bleeding among these?
–Any clinical or lab variables that could discriminate Addison’s vs other cause of chronic GI signs?
–28%
–4% – all atypical, most had GI bleed
–No
JVIM 2020, Hauck
Regarding adrenal mass FNA/cytology:
–Is it good for discriminating benign vs malignant, origin (cortical vs medullary), or both?
–What proportion are nondiagnostic?
–Complication rate? Most common complication? Proportion with hypertensive crisis?
–Estimated mortality rate and usually within what time frame?
–Origin (90-100% accuracy)
–16% nondiagnostic
–Complication rate 8%, usually bleeding, no dogs had hypertensive crisis
–Est mortality 1%, usually immediate or within several hours, one dog at 24hrs (may have been unrelated)
JVIM 2020, 2020
How does spexin affect food intake and body weight? How does it correlate with BCS in dogs?
Decr food intake and body weight
Neg correlation with BCS (low spexin –> high BCS)
JVIM 2020, Kolodziejski
Regarding transsphenoidal hypophysectomy in cats to treat hypersomatotropism:
–Post op mortality rate?
–Of survivors, percentage with improved DM control?
–Percentage that went into remission? Median time to d/c insulin?
–Percentage that had DM recurrence and median amount of time to recur?
–15% (within 1mo of sx)
–95%
–71%, 9 days
–12%, 8-9mo
JVIM 20201, Fenn
What percentage of cats that underwent transsphenoidal hypophysectomy to treat hypersomatotropism needed long term:
–Levothyroxine
–Steroids
–Desmopressin
–100%
–100%
–72%
JVIM 20201, Fenn
Name at least 2 predisposed breeds each for the following hypothyroidism categories:
–Thyroglobulin auto-Ab (TGAA)
–Familial
–Congenital central
–Congenital with goiter (caused by what deficiency)?
–TGAA: Eng setter, golden, ridgeback, cocker, boxer
–Familial: Great dane, beagle, borzoi, Giant Schnauzer
–Congenital central: Giant Schnauzer, mini schnauzer
–Congenital with goiter (caused by thyroid peroxidase deficiency): autosomal recessive in toy fox terrier, rat terrier
Explain the relationship between TRH and GH. What three tests using these can differentiate true hypothyroidism vs nonthyroidal illness (NTI)?
Hypothyroidism –> more TRH –> more GH
Tests:
–Basal GH (<1.8 –> probably NTI)
–TRH stimulated GH (post > pre, prob hypothyroid)
–TRH stimulated TSH (post > pre, prob NTI)
JVIM 2018, Pijnacker
Lethargy is commonly reported in hypothyroid dogs. Irritability and unprovoked aggression are occasionally reported. What is the effect of levothyroxine on these behaviors?
More energetic, no effect on irritability/aggression or serotonin levels (6 week study). Thus, levothyroxine is not a tx for behavior issues.
JVIM 2018, Hrovat
Are SDMA and creatinine higher, lower, or the same in hypothyroid vs euthyroid dogs? Does thyroid supplementation affect this?u
Hypothyroid dogs have higher SDMA and creat (but SDMA rarely above normal) and these usually normalize with tx
JSAP 2021, Di Paola
True or False:
The recombinant human TSH stim test is able to discriminate hypothyroid vs nonthyroidal illness in dogs with high sensitivity and specificity.
True – sens 100%, spec 93%
Post T4 >1.7 –> prob not hypothyroid
Post T4 <1.3 –> prob hypothyroid
JSAP 2021, Corsini
Answer the following regarding spontaneous primary hypothyroidism in cats based on a small study (n=7):
–Age (median and range)
–Is there a sex predisposition?
–Usually clinical or aclinical?
–Proportion that were azotemic?
–Median 7yrs, range 3.5-11yrs
–Most male
–Most aclinical (detected on routine thyroid screening)
–Half azotemic
JVIM 2018, Peterson
Answer the following regarding spontaneous primary hypothyroidism in cats based on a small study (n=7):
–Goiter was common or uncommon?
–High TSH was common or uncommon?
–Positive response to tx (incr T4, FT4; decr TSH, azotemia, goiter)
–Almost all
–All
–All
JVIM 2018, Peterson
In a small study (n=6) of congenital feline goitrous hypothyroidism:
–Age of the oldest animal?
–At least 5 common PE findings?
–Proportion that had high TSH?
1.5yrs (youngest 4mo)
PE:
–Small
–Disproportionate dwarfism
–Delayed tooth eruption, retained deciduous teeth
–Bilateral goiter
–Poor hair coat
–Lethargy
–Hypothermia
All had high TSH
JSAP 2020, Iturriaga
In a small study (n=6) of congenital feline goitrous hypothyroidism:
Time to response to levothyroxine wrt T4, TSH, CS, appearance?
–6wks normal T4
–8wks improved hair coat, activity
–10wks normal TSH
–4mo normal appearance and dentition
JSAP 2020, Iturriaga
Are the following higher, lower, or the same in nonthyroidal illness vs healthy cats? Which scale with disease severity, and which can predict 30 day survival?
–T4
–FT4
–T3
–TSH
NTIS cats – lower T4 and T3, no difference FT4 and TSH
Lower T4, T3, FT4 –> worse dz
Undetectable T4 and TSH –> dead within 30d
JVIM 2020, Peterson
For hyperthyroid cats treated with bilateral thyroidectomy, what proportion are hypo- and hyperthyroid at 6mo and long term?
6mo: 49% hypo-T, 22% hyper-T
Long term: 17% hypo-T, 44% hyper-T
JVIM 2019, Covey
Does hyperthyroidism affect platelet function?
No
JFMS 2020, Hiebert
How does IGF-1 correlate with severity of hyperthyroidism?
Inversely proportional
JFMS 2018, Rochel
Hyperthyroidism is an incidental diagnosis in ____% of cases.
24%
JFMS 2018, Watson
What proportion of hyperthyroid vs healthy cats have a palpable thyroid gland? Does thyroid gland size correlate with T4?
Hyperthyroid 80%, gland size does NOT correlate with T4
Healthy 20%
JFMS 2018, Wehner
What proportion of hyperthyroid cats presented for I-131 have cardiac changes on CXR?
What proportion needed a change in tx plan based on CXR?
43% cardiac abnormalities
6% had change to tx plan – most of these were subclinical neoplasia OR had cardiorespiratory signs that would have indicated CXR regardless
JFMS 2020, Kormpou
True or False:
FT4 by chemiluminescent enzyme immunoassay should not be used for monitoring post I-131.
True. Use FT4 by ED.
JFMS 2020, Stammeleer
Should subject based or population based ref intervals, or both be used for:
T4
TSH
FT4
T4, TSH - ok to use subject or population based ref interval
FT4 - high individuality, used subject based ref interval
JFMS 2021, Kovarikova
Does bisphenol A correlate with thyroid function?
No
JFMS 2021, Kovarikova
True or False:
Elevated SDMA in hyperthyroid cats pre-RAIT consistently predicts unmasking of CKD post RAIT.
False. Hit and miss depending on the study.
JVIM 2018, Buresova
JVIM 2020, Yu
JFMS 2020, DeMonaco
What is the outcome of an oral fixed dose 3.7mCi RAIT to treat hyperthyroidism? (% hyperthyroid, eu, overt hypo)
Did severity of hyperthyroidism impact odds of post treatment HYPOthyroidism?
Hyperthyroid 2.5%
Euthyroid 82%
Overt hypothyroid 15%
No
JFMS 2020, Yu
Does a single low dose or high dose of human recombinant TSH improve I-131 uptake in hyperthyroid cats?
No
JVIM 2018, Oberstadt
Sodium pertechnetate can be used to semi-quantify thyroid uptake prior to I-131. How can this information be used to predict which cats are at risk of persistent hyperthyroidism post I-131?
Higher thyroid/salivary gland ratio (T/S ratio) –> higher risk of persistent hyper-T post I-131
JFMS 2018, Volckeart
What percentage of Addisonian dogs have total hypercalcemia? Which three factors increase their odds?
35%
Increased odds if typical (vs atypical) Addison’s (4x), higher creat (1.5x), higher alb (4x)
JVIM 2023 Hall
Regarding Bexagliflozin in newly diagnosed DM cats:
–What percentage of cats had clinical and biochemical improvement at 2mo?
–What were at least 3 common adverse effects?
–What percentage had a serious AE? What was the most notable AE?
84%
V+, D+, anorexia, lethargy, dehydration
10% – esp euglycemic DKA
JVIM 2023 Hadd
What was associated with longer survival in dogs with pituitary macroadenomas treated with radiation?
PDHAC vs nonfunctional
Definitive vs palliative radiation
Only radiation dose affected survival. Definitive MST 1.5yrs vs palliative 8.5mo.
JVIM 2023 Rapastella
How does insulin level at the time of insulinoma diagnosis affect the likelihood of mets and the prognosis?
No effect
JVIM 2023 Petrelli
True or False: Urine and plasma metanephrines can be used to help diagnose pheochromocytoma in cats.
True – but teeny study (N = 10 healthy cats, 1 pheo cat)
JVIM 2023 Prego
Based on a small study, what cat breed might be predisposed to Addison’s?
N = 11 cats, half were British short hairs
JVIM 2023 Sieber-Rickstuhl
Which is a clinical sign of Addison’s in cats?
Weight loss despite a good appetite
Obstipation
Vocalizing
Overgrooming
Obstipation. Also see the other nonspecific Addison’s signs like in dogs.
JVIM 2023 Sieber-Rickstuhl
Addisonian cats tend to need (higher)(lower)(similar) doses of DOCP and pred compared to dogs.
Higher DOCP (start at 2.2mg/kg) and pred
JVIM 2023 Sieber-Rickstuhl
True or False: Small adrenals on AUS is highly sensitive for Addison’s in cats.
False – only half in the small study (N=11)
JVIM 2023 Sieber-Rickstuhl
Severe muscle stiffness (SMS) can occasionally occur with Cushing’s.
What is most common?
–PDHAC vs ADHAC
–Large vs medium/small dogs
–PLs vs TLs vs all four legs affected
–Dx before, at the same time, or after HAC
–PDHAC
–Medium/small dogs (<20kg)
–60% PLs only > 25% all four > 15% TLs
–Dx after HAC 62% > before 30% > same time 8%.
JVIM 2023 Golinelli
Severe muscle stiffness (SMS) can occasionally occur with Cushing’s.
How does SMS correlate with HAC control?
How does SMS affect survival?
Trilostane/mitotane does not improve SMS regardless of HAC control. No apparent good therapy.
Survival time is similar to garden variety HAC.
JVIM 2023 Golinelli
A small study showed promise in using telmisartan to help diagnose primary hyperaldosteronism in cats.
–How is the test performed (basics)?
–What would you expect in a normal vs HA cat?
–Any adverse effects?
Aldosterone suppression test
–Baseline ald –> give telmisartan –> recheck ald in 1hr
Normal cat –> lower post ald
HA cat –> no change post ald
No change to BP or K+ during the study
JVIM 2023 Fabres
Regarding plasma normetanephrines and metanephrines:
–Which has higher sens/spec to differentiate pheo vs healthy or HAC dogs?
–How do pheo dogs compare with nonadrenal illness?
Normet is better (sens 100/spec 94) vs met (sens 73/spec 94)
No difference pheo vs nonadrenal illness – so don’t rely on this test alone
JVIM 2023 van den Berg
True or False: Cats fed a wet food diet are more likely to go into DM remission and not relapse.
True
JVIM 2023 Rothli-Zachrisson
True or False: BG monitoring during sx for insulinoma helps surgeons maximize removal of tumor burden and improves survival.
True. Look for and remove tumor/mets until BG increases.
JAVMA 2023 Collgros
Answer the following about detemir.
–Intermediate or long acting? How does it achieve this rate of absorption?
–Potency compared with NPH or Vetsulin?
–In a small study of poorly controlled DM dogs, how did detemir perform compared with their previous insulins?
–How long to see maximal improvement?
–Is it safe to give even if preprandial BG is normal? Why or why not?
–Long acting. Binds albumin –> slow absorption.
–4x potency
–Detemir improved DM control, no incr risk for hypoglycemia
–Max improvement by 1mo
–Probably b/c onset of action is slow
JAVMA 2023 Harris-Samson
What is the prevalence of acromegaly in DM cats (Buenos Aires study)? Hyperthyroidism?
15%
2.5%
JFMS 2023 Miceli
What is the transtubular potassium gradient (TTKG) (basics)?
Would you expect it to be lower or higher in dogs with Addison’s vs other cause of hyperkalemia?
TTKG is a calculation comparing plasma and urine K+
Lower
JSAP 2023 Petini
