Glycated hemoglobin (EDTA)
Test to indicate average glucose concentration in RBC over their lifespan
What will these ednocrinopathies do to insulin?
HyperT4 (Thyroid hormones)
Hyperpituitarism (GH, GnRH/Progestins)
Inc ALT, AST, ALP, GGT secondary to hepatic lipidosis
Heinz bodies (cat)
>150 glucose (dogs)
HYPO Na, Cl, Phos (hemolysis -> anemia)
Proximal duodenal obstruction
Glucose 250-1000! (Stress also contributes)
(Shock or dehydration will decrease glucose)
Hyper or hypo glycemia:
Ketosis in CATTLE
Pregnancy toxemia in SHEEP
Neonatal ____glycemia in PIGS
TRH, TSH, T3/fT4/T4
Hypothalamus secretes ______ to pituitary who secretes ____ to thyroid who secretes ____
TSH (normal) rT3 (increased)
In a euthyroid sick animal (low total T4), what hormone is NORMAL compared to true thyroid sick animals (HIGH TSH)?
What hormone is INCREASED?
Idiopathic follicular atrophy
Neoplasia (carcinoma, scc)
Congenital (defective synthesis or iodine deficiency)
3 other causes of hypothyroid, besides immune mediated:
TgAA (can detect as early as 1 year old)
What test should you run before breeding 1-5 year old females to test for thyroid abnormalities?
If a GSH has pituitary dwarfism, causing hypothyroid and addisons, what category hypythyroid is this? Primary, secondary or tertiary?
Decreased appetite, Weight gain!
Non-pruritic bilateral alopecia
Weakness, mm. wasting
Mild normocytic, normochromic non-reg anemia
Target cells (leptocytes - abn lipid met)
Inc WBC - pyoderma
Inc CK (mm. atrophy)
Mild/mod inc ALT, AST, ALP
Proteinuria (glomerulonephritis, lymphocytic thyroiditis)
Euthyroid sick animals will have
Low T4 (transient)
Endocrine DZs associated are (2) _________
Antiepileptic drugs (Barbituates, Benzodiazapines)
What drugs can cause Euthyroid sickness (2)? Some include NSAIDs, Sulfur, penicillin, furosemide
(At least) 4 weeks (ideal:6-8 weeks)
How long should you wait to test an animal's T4 levels after you stops it's thyroid medications?
5 weeks (thyroid drugs) 4 weeks (other drugs)
Before doing a TSH stim test, how long must you have weaned the animal off thyroid drugs before testing? How about other drugs?
In early hypothyroid cases, what are the levels of T4, fT4 and T3? Increased, normal or decreased?
No, retest (later day)
If you take a sample from a horse and you get low T4 levels, is this DXtic for hypothyroidism? If not, what should you do next?
Polyphagic, but Weight loss!
Tachyarrythmia, HCM!! (reversible)
Panting, hypersensitivity (nervous)
Less common - V/D/Fever/Ventroflexion of neck (thiamine def, hypokalemia), ataxia (mm. weakness)
Mild/mod inc ALP and/or AST
Mild inc ALT (hepatotoxic, ishemia)
Hepatic lipidosis (anorexic) in ALP
DM or stress
1006-1060, GFR, renal, ADH
PU/PU in hyperthyroidism:
Azotemia with a USG from _____ - _____
Increased T4 causes and increase in _____
Increased GFR = hyperfiltration, which may mask _______ disease.
Decreased USG due to increased medullary flow
Thyroid hormones also will inhibit _____
No, (Serum) Total T4
If a hyperthyroid cat has a USG below 1035, can you say this is renal or prerenal? If not, what other tests should you run?
If an animal tests positive for hyperthyroidism using total T4, but you also suspect a concurrent non-thyroid DZ, when should you retest?
Owner compliance (check if correctly dosing when doing a T3 suppression stim)
When is the ONLY time you would measure T3?
CRH, ACTH, Cortisol (stress response)
The hypothalamus secretes ______ which causes a release of ______ at the pituitary, which causes secretion of ______ at the adrenal glands.
Is the most common cause of Cushings primary (adrenal cortical adenoma) or secondary (Pituitary dependent HyperA)?
Ovarian sertoli cell tumor
Non-endocrine tumors (lung)
Other causes of hypercortisolemia (2)
Glycogen, hepatopathy, ALP, bile acids
What happens IN THE LIVER when cortisol is high?
Deposition of ________
Induction of enzyme: _______ (DOGS)
Increase in ______ ______
catabolism, gluco(neogenesis) and lipolysis
What happens in TISSUES when cortisol is high?
Overall tissue _________ via
____neogenesis and ________.
Cushings can result in another endocrine disease called _____ due to ______ resistance in CATS (sometimes dogs)
PDA (ADA -> SX)
In DOGS Cushings has to be distinguished b/w PDA and ADA, becuase _____ can be treated medically.
PHARM Q: Drugs (4) used to TX Insulin dependent DM (no ketosis) =
Sulfonylureas (MOA = stimulate Beta cells to secrete insulin)
PHARM Q: Drug used to TX insulin resistant DM =
Mitotane (Ketoconazole can also be used)
PHARM Q: Drug of choice to TX Pituitary Dependent Cushings =
CYSTITIS AND RECURRENT UTI
-Truncal obesity/alopecia, Pot Belly, abdominal distention
-PU/PD (ADH suppression)
-Muscle weakness (abd. distension)/wasting
-Thin skin (opposite hypoT4)
-Pyoderma (immunosuppression and thin skin)
-Polypenia (weak resp muscles)
-Neuro signs (PDA)
Emphysematous cystitis (E. Coli proliferate and produce gas bubbles in wall)
PATH II Q: What is commonly seen with DM patents in the u. bladder?
What reproductive changes could you see in Cushings patients?
______ due to gonadotropin suppression (females)
______ atrophy (males)
CATS (But, severe thinning of skin - wounds by grooming)
What species with Cushings may not show any signs at all?
Left shift if pyoderma
Inc PCV, nRBC without regeneration
INCREASED ALP (5-45x normal)
HYPERglycemia (CATS - IRDM)
UTI without PYURIA (immunosuppressed)
LOW Urea (PU/PD)
USG - Hyposthenuric, Isosthenuric (ADH suppression)
Cushings (DM increased)
Using a serum fructosamine test, which will have a normal level of fructosamine, Cushings or DM?
How long should you GRADUALLY wean an animal off of cortisol based drugs before testing for Cushings?
Urinary cortisol:creatinine ratio (UCCR)
Name 2 SCREENING tests for Cushings (Can't use to confirm Cushings)
High (high true positives), low (lots of false + --> a lot of things can look like Cushings)
UCCR has a ____ sensitivity, but _____ specificity.
How do you avoid stress when taking a UCCR?
Sample urine in the _____ (time of day) 2 days after the vet visit
The UCCR can rule in DM, DI, Pyometra, hypercalcemia, renal/liver failure by showing an ________ (increase or decrease).
LDDS (Low dose dex suppression)
What 2 adjunctive tests asses the hypothalamic-pituitary-adrenal gland axis?
What is the ONLY SCREENING TEST that can be used to (DX)
1. Iatrogenic Cushings
3. Treatment assesment using Mitotane / Trilosane
maximally, adrenal, cortisol
The goal of a ACTH stim is to ________ stimulate the _______ cortex to make as much ________ as possible
ACTH stim will not 100% diagnose an animal with PDA (84%), ADA (51%) or iatrogenic CUSHINGS (14%). This is b/c it has a lower ________ than LDDS.
Drugs such as __________ and glucocorticoids can elevate the post ACTH value and well as increase liver enzymes (ALP).
CUSHINGS patients (All ADA and most PDA) are resistant to negative feedback of Dex, so ______ levels remain high when you give Dex.
If an animal responds by a decrease in cortisol 4 hours hours after given Dex this could mean they're healthy or have ______
There is a high false positive rate when using LDDS because lots of things like stress won't allow the animal to suppress (keep cortisol low). This means LDDS has a low _________
What are the 3 critiera used to help distinguish between PDA from ADA?
1. 4hr plasma cortisol <____microg/dl
2. 4hr plasma cortisol <______%of _______
3. 8hr plasma cortisol >______ or 1.45
No (Only 60-65% will - Some won't even suppress AT ALL)
Will ALL PDA suppress below 1.45mircog/dl at 4 hours?
Oral-LDDS (test urine instead of plasma)
If IV-LDDS and UCCR inconclusive, what other method could you use?
HDDS (10x Dex dose)
After a DX of Cushings has been made with ACTH or LDDS, how else can you confirm a PDA or ADA? What discriminatory test can you use?
NEITHER!!!! (15% of PDA won't suppress at all)
Using a HDDS test, if you don't have any suppression at all at 4hr and 8 hr, which form can you DEFINITIVELY diagnose?
What is another, relatively not available unfortunately, test to distinguish between PDA and ADA?
Plastic EDTA tube (spin down and freeze plasma ASAP)
What tube should you use to collect blood for an endogenous ACTH assay?
Occult HyperA - "Alopecia X"
Syndrome diagnosed with a _____ ___ test to measure sex hormones and aldosterone
What is the most common cause of Addisons, primary (detroyed adrenals) or secondary (pituitary deficiency of ACTH)?
Secondary (ACTH does not affect Aldosterone!)
Which form of Addison's DOES NOT have electrolyte imbalance?
Episodic frequency of dec mineralocorticoid signs =
-Weak pulse and BRADYCARDIA (High K)
-DEPRESSION & WEAKNESS
-Dehydration or HYPOTENSION
-PU/PD due to ELECTROLYTE imbalances
-Shivering, shaking, shock. collapse
-Mild, non-regenerative anemia (~MASKED)
-High Lymphocytes and Eosinophils
=REVERSE STRESS LEUKOGRAM, even when very sick
-HYPER K, Phos, HYPER Ca (n = iCa)
-HYPO Na, Cl
-Metabolic acidosis (Dec HCO3)
-Dehydration CAN MASK electrolyte LOWs
-Hypovolemia dec GFR
-Dec GFR -> PRERENAL AZOTEMIA
-Gastric hemorrhage increases UREA
-USG <1.025; med washout
What is the Na:K likely to be in:
GI DZ (Whips, Salmonella)
Severe metabolic acidosis
Breeds: Shiba inu, Shar Pei
Clotting process releases K (Lots of platelets)
What is the only endocrine test that you only have to take a blood sample for once to make a diagnosis?
What is diagnostic for Addisons using a ACTH stim?
Failure of cortisol to _______ from baseline or increase >___microg/dl
HIGH (Pituitary senses low electrolytes and is trying to tell the adrenals to make glucocorticoids! Also, there is no negative feedback coming from the adrenals)
Primary Addisons will have _____ ACTH using an endogenous assay.
Low (Pituitary ACTH deficiency - secondary Addisons)
Secondary Addisons will have _____ ACTH using an endogenous assay.
Low, Iatrogenic cushings
Using an ACTH stim test, post cortisol levels will be _____ for Addisons & ________ _______
What hormone is made my parafollicular C cells in the THYROIDgland that decreases Ca by inhibiting osteolysis and stimulates Ca excretion in the kidneys?
Actions of PTH:
___ renal absorption of Ca
___ renal absorption of Phos
Reabsorb Ca from _____
Activate _____ _ in the kidney
Primary hyperthyroidism is RARE. It can be due to parathyroid ______, ______, functional PTcarcinoma or autnomous over-secretion of PTH
Why do animals who are hyperPT get UTI?
Urinary ______ build up, causing blockage and stasis.
Shivering, twitching, seizures
Osteopenia (bone loss)
-Mild to marked hypercalcemia
-Low to normal phosphorus
-PTH high or wnl (non-hyperPT low)
If renal damage:
-Ca oxylate dihydrate crystals
Mild hyperglycemia (Ca needed for insulin release)
Apocrine gland adenocarcinoma of the anal sac
(Also gastric squamous cell carcinomas)
Name 2 neoplasims thats secrete PTHrp: