Clinical Pathology Flashcards
What is the problem with a fast bleed/ high suction?
it can cause haemolysis of the blood, or a possible vein collapse.
what happens in a slow bleed?
platelet clumping, coagulation, can be caused by low blood pressure.
What is serum derived from?
clotted blood
how do we mix the sample?
invert it 5 times
what are the 4 microscopic powers used on a microscope?
10x
40x
100x
1000x
what does FNA stand for?
Fine Needle Aspiration
what is written on a cytology slide? (labelling)
patient name, owner name, date, area the sample was taken from.
should all slides be stained in house?
no, some labs prefer to do it themselves.
should the cell layer thickness on a cytology slide be thick of thin?
thin (monolayer)
how many 1 second dips in the diff quik?
5 dips in each
label parts of a plain tube after 30 minutes
serum, blood clot
label parts of an EDTA tube after 30 minutes
plasma, buffy coat, red blood cells
what is found in plasma thats not in serum?
fibrinogen
what microscopic fibre is formed when blood clots?
fibrin
why do we separate blood from clot for long term storage?
to prevent chemicals leaching out of old or damaged cells
what are 2 methods of separating serum from a clot?
pipette, serum separator tube
what is the most versatile anti-coagulant?
Lithium Heparin
what is the best anti-coagulant for blood smears in mammals?
EDTA
what test do we use a citrate tube for?
coags, PT, PTT (blue tube)
What test do we use a FLOX tube for?
glucose levels (grey tube)
what does serum centrifuged before clot retraction result in?
the serum becomes a gel (platelets will be spun out before they get a chance to contract fibrin in the clot)
where should we leave a sample for clotting? how long?
left to stand on the bench at room temperature for 30 minutes
how many times do we invert a serum separator tube?
5 times after the sample is taken
how do we store a serum separator tube?
left at room temperature to separate then serum can be frozen
when do we centrifuge a SST?
after 30 minutes
when should the SST sample be poured off?
within 60 minutes
which blood cells are responsible for clot retraction/ contraction?
platelets or thrombacin
why is it best to fast an animal before collecting blood?
to avoid lipemia
what is a better blood smear at gross level?
blood will be spread out evenly over the slide, not too skinny
what is a better blood smear at microscopic level?
cells wont overlap
label blood smear
Red blood cells (erythrocytes), platelets (thrombocytes)
label microhaematecrit tube
plasma, buffy coat, red blood cells
what is an anaemic PCV?
dogs: less than 37%
cats: less than 30%
healthy PCV?
dog: 45%
cat: 35%
healthy TP?
cats and dogs: 70g/L
do we read the meniscus from the top or bottom?
bottom
what are the 2 blood tests which help diagnose dehydration?
PCV, TPP
what is an enzyme?
a protein produced by a living cell that increases the rate of a chemical reaction.
how is blood stored within 30 minutes?
at room temperature (around 20 degrees)
how is blood stored between 30 mins - 48 hours?
in the fridge (around 4 degrees)
list 2 enzymes tested to investigate liver injury.
ALP, ALT
list 2 enzymes tested to investigate liver function.
ammonia, bile acids
list 2 enzymes tested to investigate pancreatic injury.
amylase, lipase
list 2 enzymes tested to investigate kidney function.
urea, creatinine
what is the pigmented liver metabolite responsible for jaundice?
bilirubin
detecting antigens - do they detect infection and previous exposure?
yes
what do antibodies do?
detect antigens, formed as an immune reaction to fight infection
when can antigens be detected?
2-3 weeks after the infection
how long can antigens remain in the body?
months or year after infection
when should urine be refrigerated?
if it isnt going to be tested within 30 minutes
what are some changes that occur to urine with age?
glucose levels fall, pH rises, bacteria usually proliferate, renal tubular casts break up.
why do we note urine collection method?
it indicates an expected level of contamination by bacteria and blood
when can we dipstick a refrigerated sample?
when it has warmed back to room temperature
why do we hold the dipstick horizontally?
so that the urine from the different pads dont mix
why do we not remove desiccating gel from dipstick bottle?
if it is removed the moisture can ruin the dipsticks, they absorb moisture
should we refrigerate dipsticks?
no
non-haemolysed blood in urine dipstick is indicated by? indicates what?
it is indicated by red spots, indicates the presence of intact red blood cells
which 2 urine dipstick tests are considered inaccurate?
USG (specific gravity) and leukocytes
which 2 tests may be affected by flea droppings on a urine dipstick?
blood and protein
should pH of urine always be recorded?
yes
advantage and disadvantage of collecting urine via cysto.
advantage: less contamination, sterility
disadvantage: invasive, could be contaminated by blood on the needle
what does turbidity mean?
cloudiness
what does flocculent mean?
floating particles
list 2 gross characteristics of urine other than turbidity.
colour, smell, volume
list 3 alternatives for “coffin lid” crystals found in cat and dog urine
struvite, triple phosphate, magnesium ammonium phosphate
what is the zoonotic disease contracted from dog urine?
leptospirosis
what is the parasite egg found in dog faeces which is dangerous to humans?
hydatid tapeworm
how much poo is needed in faecal floatation decide?
1ml
how long should a faecal floatation device float for?
10-20 minutes
whipworm egg looks like:
a casserole dish
hookworm egg looks like:
oval with big circles in the middle
roundworm egg looks like:
big circle with fuzzy edges
tapeworm egg looks like:
circle with shaded inside,lines around the edge
eggs that look like a string of circles:
coccus
eggs that look like rods:
bacillus
adult dog faecal floatation with mucoid blood, flecked diarrhoea is which worm?
whipworm
what is the name of the stain used to divide bacteria into 2 groupings?
gram stain
what is the purpose of a bacterial culture plate?
culture and sensitivity
what is a fungassay?
test for ringworm
where do we grow a bacterial culture plate?
on a shelf, away from direct sunlight
how should the cap be placed on a culture plate?
partially closed
how often should the culture plate be checked?
daily for up to 2 weeks
a pathogenic fungus is indicated by the appearance of what?
colour change during early growth
how is a deep skin scraping performed?
the skin is squeezed to get the mites out of the follicles, a blunt scalpel is used
how many superficial skin scrapings are needed for scabies?
up to 10
should the scalpel blade be sharp or blunt?
blunt
what 3 things make skin adhere to slide?
sterile lube, paraffin oil, water/saline
how do we minimise tissue deterioration of a biopsy before placing in formalin?
keeping moist with sterile physiological saline
