rbc Flashcards
what are the most important parameters?
rbc count and hemoglobin concentration and or function
sample for spectrophotometric hgb count
whle blood sample
spectrophotometric hgb count - what is reagent and what does it do?
K3Fe(SCN)6
hemolyse rbc and turn fe2+ to fe3+
spectrophotometric hgb count - equation and normal range
(Esample/Estandard)x standard conc
normal: 18-20 mmol/l or 12-18 g/dl
spectrophotometric hgb count - what is measured?
sum of hgb from hemolysed blood and free hgb from plasma
ox binding capacity of hgb increased by:
- decreased 2,3 dgp level in rbc
- decreased pCO2 in blood - resp alkalosis
- increased pH in blood - alkalosis
- decreased temp - hypothermia
ox binding capacity of hgb decreased by:
- increased 2,3 dpg level in rbc
- increased pCO2 - resp acidosis
- decreased pH - acidisis
- increased temp - hyperthermia
oxygen saturation
amount of oxygenated hgb compared to whole sample
a/v sat
arterial: 95-99%
venous: 80-90%
methemoglobinemia
high amt of methemoglobin due to oxidative damage
nitrite, free radicals, paracetamol, onion
improper function of methemoglobin reductase enzyme
causes of increased hgb conc
- relative polycytaemia - dehydration
- absolute polycytaemia
causes of decreased hgb conc
- relative oligocytaemia - hyperhydration
- absolute oligocytaemia - anemia
rbc burker chamber
- edta anticoagulated blood
- 200x dilution
- divide nr of counted cells by 100, that give the number in tetra per litre
- poor accuracy10-25% error
estimated rbc
- if normal rbc volume is suspected
- (ht l/l / 5) x 100 = rbc terra/l
rbc by automatic cell counter
- impedance correlated with size
- counted as rbc if between 40-100 fl
- aggregated rbc not counted (immunohaemolytic anemia)
- cold agglutination
normal rbc count
4,5-8 tera per liter
derivative parameters - what test do we need?
- what information do we get?
- ht
- packed cell volume
- rbc count
- hgb concentration
- info about avg size and colour of rbc
- humn, dogs, maybe cats
Mean corpuscular haemoglobn - mch
- indicate average hgb content of rbc
- hgb g/L / rbc count terra per liter = mch
normal mch
- 12-30 pg
- young animals 28-32 pg
increased/ decreased mch
- inc: hyperchromasia
- dec: hypochromasia
mch value horse, rominant, dog, cat
- horse: 12-20 pg
- ru: 8-17 pg
- dog: 15-24 pg
- cat: 13-17
mean corpuscular volume
- indicate average size of rbc
- macro, normo, micro - cytic rbc
- pcv / rbc count x 1000 = mvc fl
mcv horse, ru, dog, cat
- horse: 37-58 fl
- ru: 42-52 fl
- dog: 63-75 fl
- cat: 40-53 fl
normal mvc
60-70 fl
variation in mvc
- horse, cat have smaller rbc
- young have larger, old have smaller
- akita have small
- poodle have large
causes of microcytosis
- chronic blood loss
- iron, copper, pyridoxine deficiency
- portosystemic shunt
causes of macrocytosis
- !! mostly regenerative anemia
- polycytaemia absoluta vera
- vit b12, folic acid, cobalt deficiency
- erythroleukemias
mean corpuscular hemoglobin concentartion
- indicate avrg hgb conc of erythrocytes
- hyper, normo, hypo chromic rbc
- hgb/ pcv = mch/mcv = mchc
mchc horse, ru, dog, cat
- horse: 31-37 %
- ru: 30-36%
- dog: 32-36%
- cat: 30-36%
normal mchc
300- 350 g/l aka 30-35%
decreased mchc
- hypochromasia
- new born
- regenerative anemia
- iron deficiency anemia
increased mchc
- hyperchromasia
- erythroleukemia
- b12, folic acid, cobbalt deficiency
- immunohemolytic anemia
- lead poisoning
- splenectomy
what happens if the animal has macrocytemia, hypochromasia and high number of erythrocytes?
high mvc, low mchc
regenertive anemia
what happens if the animal has normocytemia, normochromasia and normal or decreased mch
normal mvc and mchc
non regenerative anemia
what happens if the animal has microcytaemia, hypochromasia (decreased hb synthesis)
low mvc, low mchc
- iron, copper, piridoxine deficiency anemias
- liver failiure
- portosystemic shunt
what happens if the animal has microcytaemia, normochromasia
low mvc, normal mchc
a normal japanese akita doggo
what happens if the animal has macrocytaemia, normochromasia (impaired dna synth)
high mvc, normal mchc
- felv
- b12, copper, folic acid deficiecy
- erythroleukemia
- poodle macrocytosis
red cell distribution width, platelet distribution width
where the curve crosses the 20% line -> p1, p2
rdw dog and cat
- rdw dog: 12-16%
- red cat: 14-18%
pdw dog, cat
- pdw dog: 6-8%
- pdw cat: 7-12 %
what does short/long rdw mean?
- short rdw means non regenerative process
- long rdw means regenerative process
how does brylliant-cresil stained rbcs look like?
- reticulocytes are young differentiated rbc with basophil punctates after rrna
- reticulocytes with big blue aggregates are younger
- cats have punctated form
. horse and ru dont have reticulocytes in peripheral blood
what is appearance of reticulocytes a sign of?
regenerative process
function of rbcs
- reticulocytes work as mature rbc, bind o2
- young nucleated rbc cannot bind o2
what can cause maturation arrest?
- b12 deficiency
- folic acid deficiency
- felv
wich cell do we count to check if its regen or non regen
reticulocytes, not nucleated rbc
regenerative anemia
- good prognosis
- enough new rbcs produced in bone marrow to replace loss
- severe anemia - more intensive prod
what smaple is used for brylliant cresin staining
1:4 na-citrate whole blood
what sample is used for vital staining
1:4 fresh whole EDTA blood
how do we count reticulocytes?
count 100-1000 rbc and take percentage of reticulocytes
normal reticulocyte count
2-3%
why should we double check the reticulocyte count or pvc? correction
- older rbcs are more sensitive to damage and may die faster, then we can only find younger cells
- when we need to concider the severity of the anemia. to differentiate regenerative and non regenerative anemias
corrected reticulocyte count
- reticulocyte % x rbc count
- normal is less than 0,06 x terra per litre
corrected reticulocyte percentage
- (Ht patient / Ht average) x reticulocyte %
- normal: less than 1-2 %
- ( normal Ht dog 0,45, cat 0,37)
causes of increased reticulocyte count
- regenerative anemias: acute or chronic blood loss, haemolytic anemia, nutrient deficiencies
what does osmotic resistance of rbc depend on?
- ph of plasma
- temperature
- osmotic concentration of plasma and reagents
- rbc membrane status
- regenerative status
- hbf content of rbc
what does osmotic resistance analysis test?
- membrane function
- specific damage
- physical damage
what causes decreased rbc membrane resistance?
- chronic haemolytic anemia: extravascular hemolysis,
- chronic immunomediated hemolytic anemia
- pyruvate kinase or glucose 6P dehydrogenase deficiency
methemoglobin reductase deficiecy
dilution line test
make nacl dilution line 0,3% to 2,5%
drip blood samples into different concentrations
centrifuge and check upper layer for hemolysis
three test tube test
- tube one 0,9% nacl and sick animal blood
- tube two: 0,54% nacl and sick dog, 0,72%nacl and sick cat
- tube 3 0,54 or 0,72% nacl and healthy animal
what do we expect to happen in tube 1
some hemolysis occur if there is an intravasal hemolytic crisis eg babesia
what do we expect to happen in tube 2
severe hemolysis
what do we expect to happen in tube 3
nothing should happen, this is control tube! if anything happens, you fucked up hehe
what sample do you use for smears
fresh samples
what gross signs do we check in a smear
- rouleau formation - coin formation often in horse
- rbc aggregates
- large cells often in horse
- thrombocyte aggregations
explain intense staining of smear
- polychromasia and hyperchromasia
- more hgb in rbc
- rna or nuclear remnants
- regenerative
explaine weak staining of smear
- hypochromasia
- low hgb content
- iron and other nutrient deficiency
name the different size/shapes of rbc
- macrocytosis: large cells
- microcytosis: small cells
- anisocytosis: variable size, iron def, regenerative
- poikylocytosis: variable shape and color
name young nucleated rbcs
- proerythroblast
- basophil erythroblast: normocyte, normoblast
- polychromatophil erythroblast: normocyte/blast
- acidophil erythroblast: normo..,
young but mature rbc
reticulocyte
what does appearance of young rbc tell us?
- regenerative anemia
- spleen or bone marrow disease
- leukemia
- extramedullar erythrocyte prod
- lead toxicosis
name the various forms of adult rbcs
- reticulocyte
- spherocyte
- stomatocyte
- acanthocyte
- schysocyte
- anulocyte
- codocyte
- echynocyte
- sickle cell
reticulocyte
- regenerative anemia
- chronic iron def
- hemolysis
- acute or chronic blood loss
spherocyte
sensitive rbc membrane
- immunomediated hemolysis
stomatocyte
- increased prod, regenerative
acanthocyte
- rbc membrane failiure
- lipid metabolism disorder
- hepatopathies
schysocyte
traumatic or toxic damage
- uremia, parasites, dic
anulocyte
iron deficiency anemia
codocyte
regenerative process
echynocyte
lab error
sickle cell
rbc damage
hb globin chain malformation
name the inclusion bodies
- heinz body
- howell-jolly body
- basophilic punctuates
- hb inclusions
heinz body
- o2 effect, oxidative damage to rbc
- cat, methemoglobinaemia
howell-jolly body
- b12 deficiency
- increased production
- splenectomy
basophilic punctuates
- regenerative process
- young rbc of cat
- physiological in ruminants
- lead poisoning
hb inclusions
- hb damage
- increased rbc prod
- regenerative anemia
name three rbc parasites
- babesia spp
- ehrlichia canis
- dirofilaria immitis
serum iron measurement what do we test, normal value
- if we suspect iron deficiency, this test proves it
- normal sefe 18-20 mikromol/l
iron metabolism
- fe3 complexes in food
- stomach acid frees iron 3 from complex
- duodenum: fe3 to fe2 by ascorbic acid
- jejunim mucosa: iron bind to apoferritin, stored as ferritin
- in plasma iron is oxidised to fe3 and transported by transferrin
transferrin
only 30% saturated
acute phase protein produced in liver
ferritin
store iron in spleen, liver and bone marrow
also in macrophage cells but less utilizable
what sample do we need for serum iron measrement and why
serum sample, because fibrinogen content of plasma may disturb measurement
causes of low serum iron conc
- chronic blood loss
- decreased intake
- impaired gastric, duodenal, jejunal function
causes of high iron content
iron toxicosis
total iron binding capacity test
- give info about transferrin content
- first measure serum iron, then add fe solution to serum to fully saturate all transferrins
- tibc is serum iron content + free transferrin
normal tibc
50-80 mikromol per litre
causes of low tibc
- chronic inflammation
- chronic liver failiure
- neoplastic disease
causes of high tibc
- iron deficiency anemia
- not severe: normal iron level, high tibc
- severe: low iron level, high tibc
iron saturation equation and normal value
- (sefe / tibc) x 100
- normal 20-55%
lab findings in hemolysis
decreased:
- pcv
- haptoglobin
- rbc osmotic resistance
increased:
- reticulocytes
- total bilirubin
- indirect bilirubin
- lactate dehydrogenase 1 and 2
- urobillinogen and hgb in urine
shape and color:
- polychromasia, poikilocytosis
- leukocytosis
- spherocytosis
- jaundace
- hyperchromatic stool
