Exam 3 Flashcards
what things interfere with refractometer readings
lipids
hemoglobin
bilirubin
what does electrophoresis measure?
albumin
𝛼-glob (app)
𝜷-glob (app & ig)
𝛾-glob (ig)
if you want to measure specific proteins (ig, fibrinogen, CRP, etc.) what would you do
protein assay
Explain the difference between Serum & Plasma.
serum - anticoagulant, albumin & all globulins
plasma - clotted, albumin, globulin minus fibrinogen
mechanisms of hypoalbuminemia
- decreased albumin production
- selective loss of albumin
causes of decreased production of albumin
- hepatic failure (most common)
- starvation/malabsorption
- Exocrine Pancreatic Insufficiency
- acute phase protein response
causes of selective loss of albumin
glomerular disease such as amyloidosis
how do you characterize:
decreased albumin
decreased globulin
what are your DDx?
panhypoproteinemia
blood loss (most common)
GI disease, severe exudative skin dz/severe burns
how do you characterize:
decreased albumin
increased globulin
what are your DDx?
hypoalbuminemia
hyperglobulinemia
- decreased production of albumin due to hepatic failure (most common), starvation, malabsorption, EPI or APP response
- selective loss of albumin due to glomerular disease (amyloidosis)
how do you characterize:
increase albumin
what are your DDx?
hyperalbuminemia
always dehydration
how do you characterize:
decreased globulins
what are your DDx?
hypoglobulinemia
failure of passive transfer or immunodeficiency diseases
Samples to submit when testing for monoclonal gammopathy/monoclonal immunoglobulin or free light chains/Bence-Jones proteinuria.
monoclonal gammopathy/monoclonal immunoglobulin = SERUM
free light chains/Bence-Jones proteinuria = URINE
Explain the Concepts of Positive & Negative Acute Phase Proteins.
(+) APP = increase with inflammation
(-) APP = decrease with inflammation
positive acute phase proteins
haptoglobin
SAA
alpha1 acid glycoprotein
fibrinogen
C-reactive protein (CRP)
negative acute phase proteins
albumin
transferrin
what does fibrinogen increase with?
inflammation & dehydration
what are the suggestive levels of dehydration of the plasma protein:fibrinogen in equine and ruminants?
equine pp:fb < 15 inflam
ruminants pp:fb < 10 inflam
causes of prerenal azotemia with increased BUN & creatinine
decreased perfusion of the kidney due to dehydration, shock, hypovolemia or cardiac disease
causes of prerenal azotemia with increased BUN and unaffected creatinine
increased protein catabolism due to high-protein diet, starvation, fever, GI bleed, massive necrosis or prolonged exercise
causes of renal azotemia
kidney inability to excrete BUN/Cr
cause of postrenal azotemia
obstruction (blocked, tumor, urethral stones)
uroabdomen (trauma, prolonged obstruction, severe inflam)
how does urine specific gravity determine adequate or inadequate renal function?
what information does USG give?
used clinically to decide if kidneys are concentrating urine; measures solute concentration
info on hydration status and the concentrating ability of kidneys
what characterizes “isosthenuria”? what does this suggest? when is this an appropriate response?
USG 1.008-1.012
suggestive that neither sig concentration nor dilution of glomerular ultrafiltrate occurred
can be normal under certain hydration conditions
what does a fixed isosthenuric commonly mean?
end stage renal disease
if USG is high what is this indicative of?
prerenal
if USG is low or isosthenuria what is this indicative of?
renal
dog USG
> 1.030
cat USG
> 1.035
horse and cow USG
> 1.025
horse common pattern of renal disease
increased BUN
increased Cr
decreased P
increased Ca2+
cat & dog common pattern of renal disease
increased BUN
increased Cr
increased P
decreased Ca2+
what abdominal fluid creatinine value is indicative of a uroabdomen
abdominal fluid:serum creatinine ratio > 2-fold
UPC > 5 with clean/quiet sediment (no WBC or RBC) is indicative of what?
glomerular disease
3 types of proteinurea and where the increased protein arises
- preglomerular - outside urogenital tract - hyperproteinemia, fever, exercise
- glomerular - glomerular membrane
- post-glomerular - renal tubule, inflammation or hemorrhage
utility of UPC
measure urinary protein excretion because creatinine is excreted in uniform quantities
when to use UPC
interpreted in light of a urine specific gravity test and sediment
pros and cons of voided sample
pros: easy, cheap, owner can do it
cons: contamination
pros and cons of cystocentesis
pros: best for culture, bypass repro tract in females, mainly used in SA
cons: enterocentesis or RBC
pros and cons of catheter sample
pros: best for culturing LA
cons: requires sterile technique and risk of iatrogenic UTI
best container for urine samples
completely sealed, hard plastic container, label as urine with patient ID, name, date and species
storage technique for urine samples
keep at room temp if testing within 30-60min
if refrigerated warm to room temp for 20min
4 steps of performing a complete UA
- appearance (color & clarity)
- concentration (refractometer & USG)
- biochemistry
- microscopy
for urine sediment prep, how much do you want to decant
10-fold
first step of a urine sediment wet-mount exam
- lower the condensor
what obj do you use to scan for epithelial cells, larger crystals and casts
10x
what obj do you use to scan for RBC, WBC, bacteria, yeast, and smaller crystals
40x
do you ever add oil to a urine sediment wet mount exam
NO
List which dipstick tests are used?
pH
protein
bilirubin
blood/hemoglobin
glucose
ketones
sources of error for dipstick tests
handling - sunlight, aging, uncapped urine
strip interference - peroxide/bleach, formaldehyde, moisture, expired strips, cold urine, strip contamination with hand
normal pH for carnivores, herbivores and dairy cattle
what does prolonged room temp cause pH to do? what crystals form?
carnivores 5.5-7.5
herbivores 7+
dairy cattle 6-7
false alkaline pH due to prolonged room temp, struvites
when would ketones be found in the urine
is (+) or (-) for ketones accurate?
(-) energy balance - diabetic ketoacidosis, cattle ketosis, low carb diet, low glucose, prong fast
(+) likely
(-) doesn’t rule out
what ketone is detected with the dipstick? what ketone needs to be measured in the serum?
acetoacetic acid with strip
BHB in serum??
presence of bilirubin in the urine
male dogs
liver disease, hemolytic disease, prolong fast, starvation, fever
what amount of blood in the urine is normal
hematuria < 5 cells/hpf
squamous epithelial cells contaminants
common from genital tract, distal urethra, prepuce
transitional cell contaminants
inflammation or neoplasia
renal tubular cell contaminants
renal tubular injury
normal WBC in urine
0-5/hpf
lipid droplets present in urine?
normal in cat urine
renal tubular cell degeneration
nephrotic syndrome
cellular casts are indicative of…
some level of acute renal tubular pathology
gives concurrent info not amount of damage
granular casts are indicative of…
some level of renal pathology - cellular, Hgb, Myoglobin, bilirubin
waxy casts are indicative of…
chronic renal pathology
most concerning
hyaline casts are indicative of…
rehydration post dehydration
glomerular or myeloma-related proteinuria
fever
how can you confirm bacteria in urine?
wright’s or quick stain
struvites (magnesium ammonium phosphate) can be due to…
urine retention
infection with urease-producing bacteria
uroliths
prolonged room temp
most common crystal in healthy animals
- struvites
- calcium oxalate dihydrate
calcium oxalate dihydrate crystals due to…
urolith
hypercalcemia
calcium oxalate monohydrate crystals due to…
ethylene glycol (antifreeze) toxicity
bilirubin in urine can be due to…
normal in concentrated male dog urine
hemolytic disease
liver disease
starvation
bilirubinemia
calcium carbonate crystals due to…
normal in horses/herbivores
uroliths in small ruminants/steers
amorphous crystals due to…
uroliths
mimic cocci bacteria - stain and verify
ammonium biurates due to….
normal in healthy Dalmatians & english bulldogs
liver disease (portosystemic shunt)
uroliths
cystine crystals due to…
always abnormal
many pure and mix breed dogs
metabolic disorder of cystine metabolism - prone to uroliths
best test for dogs for hypothyroidism
tT4, fT4 & cTSH
best test for horses for hypothyroidism
TSH or TRH response test
best test for cats for hyperthyroidism
tT4 (single test OK), if normal-high do 2nd test
fT4
majority of dogs have what type of acquired hypothyroidism (primary, secondary or tertiary)
primary - thyroid gland itself
majority of cats have what type of hyperthyroidism (primary, secondary or tertiary)
primary - one or both thyroid glands
a cat with weight loss, polyphagia, PUPD, hyperactivity, restlessness, diarrhea, vomiting, skin changes, resp signs, “sick cat”, 12 year old cat acting young
hyperthyroidism
a dog with …
dermatologic (endocrine alopecia, pyoderma, otitis, demodicosis, facial myxoedema)
metabolic (lethargy, inactivity, weight gain)
neuromuscular (weakness, ataxia)
hypothyroidism
most common cause of hypothyroidism in foals? adults?
foals - I def or ingestion of goitrogen
adults - neoplasia
foals that are affected at birth, and have goiter, weakness, incoordination, poor suckle reflex, ossification/tendon defects
hypothyroidism
dog lab abnormalities with thyroid disease (hypothyroidism)
hypercholesterolemia
mild nonreg anemia
cat lab abnormalities with thyroid disease (hyperthyroidism)
increased liver enzymes (ALT, ALP) most consistent
erythrocytosis
excitement leukogram
decrease cholesterol
increased BUN
false decrease in fructosamide
most common endocrinopathy in cats
hyperthyroidism
most common endocrinopathy in dogs
hypothyroidism
what is euthyroid sick syndrome
decrease total T4
normal fT4 and TSH
majority of dogs have what type of cushing’s (hyperadrenocorticism)
pituitary-dependent - resulting in bilateral adrenocortical hyperplasia
cause of equine cushing’s (hyperadrenocorticism)
pituitary adenoma
majority of cats have what type of cushing’s (hyperadrenocorticism)
pituitary-dependent
dog addison’s (hypoadrenocorticism) primarily due to
adrenocortical failure from destruction of adrenal cortex from immune-mediate, granulomatous disease, infarct, neoplasia or idiopathic
what test is often used to rule out Cushing’s in dogs and cats
urine cortisol:creatinine ratio
LDDST in dogs - what is indicative of…
decreased cortisol response?
4hr & 8hr not suppressed?
4 hr suppressed, 8hr not?
decreased cortisol response = normal
4hr & 8hr not suppressed = PDH or ADH
4 hr suppressed, 8hr not = PDH
only test for iatrogenic cushings?
ACTH stim test
ACTH stim test - what is indicative of..
mild increase in cortisol?
marked increase in cortisol?
no change in cortisol?
mild increase in cortisol = normal
marked increase in cortisol = PDH or ADH
no change in cortisol = iatrogenic
endogenous ACTH
normal-increased?
low-undetectable?
normal-increased? PDH
low-undetectable? ADH
dog with PUPD, polyphagia, pendulous abdomen, panting, hepatomegaly, muscle weakness, lethargy, lameness, endocrine alopecia, pyoderma, demodex, calcinosis cutis
hyperadrenocorticism “Cushing’s”
dog lab abnormalities with Cushing’s
stress leukogram
thrombocytosis, erythrocytosis
hypercholesteralemia
hyperglycemia
increased ALP
low USG
equine with hirsutism and inability to shed winter coat has?
pituitary pars intermedia dysfunction (PPID)
lab abnormalities in equine with Cushing’s
stress leukogram
anemia
hyperglycerma, hyperlipidemia
increased liver enzymes
most common equine endocrinopathy
PPID
why do you not want to use a dexamethasone suppression test in horses?
increased risk of laminitis
recommended testing for Cushing’s in horses
endogenous ACTH
TRH stim
a cat with uncontrollable diabetes mellitus, PUPD, polyphagia, weight loss, lethargy, weakness, dermatopathies
Cushing’s
lab abnormalities in cats with Cushing’s
stress leukogram
normal liver enzymes and cholesterol
concurrent DM
usually inconsistent
recommened test in cats with Cushing’s
LDDST
a young-middle aged dogs, females > males, vague clinical signs, intermittent illness, GI (vomit/diarrhea), lethargy, anorexia, polyuria, shaking, abdominal pain, addisonian crisis
hypoadrenocorticism “addisons”
lab abnormalities in a dog with hypoadrenocorticism
lack of stress leukogram
non-regenerative anemia
azotemia & hyperphosphatemia
hyponatremia, hypochloremia, hyperkalemia (Na:K < 27:1)
recommended test for suspected dog with Addison’s
baseline cortisol < 2 ug/dL then ACTH stim = no/low cortisol <2 ug/dL
what is the gold standard test for Addison’s
ACTH stim
