Clinical Pathology in Endocrinopathies Flashcards
1
Q
Thyroid
A
- Sets basal metabolic rate
- req’d for growth/development of Skeletomuscular syst, and turnover for adults
- Essential for Normal catecholamine actions
- Maintenance of hair and coat, and sebaceous gland
- Required for normal lipoprotein lipase activity
- Maintains hepatic LDL receptor synthesis for rem of cholesterol from blood
- Required for normal neural transduction
2
Q
Hypothyroidism
about
A
- Mostly dogs
- Immune-mediated/idiopathic
- Dec synth T3 and T4
3
Q
Hypothyroidism
CS
A
- Lethargy
- Inactivity
- Dullness
- Weight gain w/o inc appetite
Other CS
- alopecia
- dull hair coat
- seborrhea
- cold intolerance
4
Q
Hypothyroidism
Clin path
CBC
A
- CBC
- mild non-regenerative anemia (<50% dogs)
- thyroid may have stim effect on EPO
- Dec O2 consumption
- May see codocytes (Target Cells)
- Membrane change related to inc cholesterol
- mild non-regenerative anemia (<50% dogs)
5
Q
Hypothyroidism
Clin path
Chem
A
- Fasting hypercholesterolemia (~75% dogs)
- Fasting hypertriglyceridemia
- Thyroid hormones stim lipid metabolism
- Net effect of hypothyroidism: accumulation of plasma lipids
6
Q
Hyperthyroidism
about
A
- Most common in cats
- hyperplasia or adenoma of thyroid tissue
7
Q
Hyperthyroid
CS
A
- Weight loss (92%)
- Polyphagia (61%)
- Polydipsia/polyuria (47%)
- Inc activity/restlessness (40%)
- GI (39%)
- Vomiting (38%)
- Skin changes (36%)
8
Q
Hyperthyroid
PE findings
A
- Palpable thyroid
- Thin
- Tachycardia
- Hyperactivity/difficult to examine
- Heart murmur
- Skin changes
9
Q
Hyperthyroid
CBC
A
- RBC parameters can be normal
- half may have MILD elevated PCV
- stim EPO
- Inc tis demand for O2
- WBC: +/- stress leukogram
10
Q
Hyperthyroid
Chem
A
-
Mild to moderate elevation of ALT and/or ALP
- very common
- both usually elevated, one almost always
- Marked elevation in liver enzymes
11
Q
Weight Loss despite good appetite
A
- hyperthyroidism
- Diabetes mellitus
- Poor diet quality/starvation
- GI dz
- hyperadrenocorticism
*remember, Liver Dz not on this list, palpate THYROID
12
Q
Hyperthyroidism
and Inc ALT
A
- Possibly from hepatic hypoxia
- inc O2 use in hyperthyroid state
- concurrent heart dz and hepatic congestion possible
13
Q
Hyperthyroidism
and Inc ALP
A
- Inc ALP
- some is from bone isoform
- some may also be from liver (cholestasis)
14
Q
Hyperthyroid
Other chem panel changes
A
- Azotemia
- hyperthyroidism inc renal blood flow and GFR
- Could be due to concurrent underlying dz
- chronic kidney dz
- heart dz
15
Q
Adrenal Glands
Layer nameses
A
- Zona Glomerulosa (outside)
- Zona Fasiculata
- Zona Reticularis
- Medulla
16
Q
Adrenal glands
About the layerses
A
- Zona Glomerulosa: SALT
- secretes mineralocorticoids (aldosterone)
- Na+, K+, and water homeostasis
- Zona Fasiculata: SUGAR
- Glucocorticoids (Cortisol)
- Glucose homeostasis plus others
- Zona Reticularis: SEX
- secretes sex steroids (androgens)
17
Q
Cushing’s
A
- Hyperadrenocorticism
- Overproduction of cortisol by adrenals
- pituitary neoplasm
- adrenal cortical neoplasm
- CS due to excess cortisol
- Most common in dogs
18
Q
Glucocorticoid function
A
- gluconeogenesis and glycogenesis
- Insulin antagonist
- Inc lipolysis
- anti-inflammatory
- inc appetite
- dec neut migration => inc blood neuts
- circulating lymphopenia and eosinopenia
- maintains normal BP
- inhibits wound healing
- opposes ADH, dec release
19
Q
Cushings dz manifestations
A
- Thin skin
- Bilateral, symmetrical alopecia
- Acne
- cutaneous hyperpigmentation
- cacinosis cutis
- Abdominal enlargement
- muscle wasting of extremeties
- hepatomegaly
- Panting
- bruising
20
Q
Cortisol
CBC
A
- RBC can be normal
- Mild inc PCV (bone marrow stim)
- WBC: Stress leukogram
- +/- thrombocytosis (don’t know why)
21
Q
Cushing’s
Chem
A
-
Inc alk phos (can be extreme)
- steroid induced isoform DOG ONLY THING
- some possibly from hepatopathy
- Inc ALT (markedly less than ALP)
- some leakage from liver if steroid hepatopathy
- Inc cholesterol
- cortisol imp in lipid metabolism
- Inc fasting blood glucose
- cortisol = insulin resistance
22
Q
Cushing’s
UA
A
- Proteinuria
- mild
- may be glomerular
- May be due to UTI (culture urine)
- UTI (silent UTIs)
- immunosuppression
- dilute urine
- urine retention
- may not see WBC inc
- Dilute urine
- cortisol interferes with ADH
23
Q
Addison’s
A
- Hypoadrenocorticism
- Destructino of adrenal cortex
- Immune-mediated
- Idiopathic
- Clinical signs from lack of
- glucocorticoids (cortisol)
- mineralocorticoids (aldosterone)
- Most common in Dog
24
Q
Mineralocorticoids
functions
A
- aldosterone
- produced by zona glomerulosa of adrenal cortex
- produced in response to
- stim of renin-angiotensin system
- hyperkalemia
- inc ACTH
- promotes renal reabsorption of sodium and chloride
- promotes excretion of potassium
25
Q
Addison’s
CS
A
- related to lack of cortisol
- often waxes and wanes
- Lethargy, weakness
- Vomiting, diarrhea, GI bleeding
- Polyuria/Polydipsia
-
Addisonian crisis
- Hypobolemic/dehydrated
- bradycardia