Approach to anaemia (Yr3)

Question 1

what is anaemia?

Answer 1

reduction of the RBC mass

Question 2

what are the three causes of anaemia?

Answer 2

inadequate production by bone marrow
increased destruction
loss (haemorrhage)

Question 3

which of the three overall causes of anaemia would be non-regenerative?

Answer 3

inadequate production

Question 4

which of the three overall causes of anaemia would be regenerative?

Answer 4

increased destruction (some exceptions)
haemorrhage/loss (not regenerative enough)

Question 5

how do red blood cells typically appear when anaemia is being caused by inadequate production from bone marrow?

Answer 5

normocytic normochromic

Question 6

how do the red blood cells typically appear in anaemia from increased destruction?

Answer 6

macrocytic hypochromic (lots of reticulocytes)

Question 7

how do red blood cells usually appear in cases of anaemia caused by haemorrhage?

Answer 7

microcytic hypochromic (lack of iron)

Question 8

what feature of blood is seen in cases of anaemia caused by haemorrhage?

Answer 8

hypoproteinaemia (whole blood loss)

Question 9

how do erythrocyte change in response to anaemia?

Answer 9

2,3-DPG increases to lower the haemoglobin affinity for oxygen to improve oxygen delivery to peripheral tissues

Question 10

what causes the haemic murmur?

Answer 10

changes in the blood viscosity due to anaemia

Question 11

what is the PCV of a mild anaemia in dogs?

Answer 11

30-36%

Question 12

what is the PCV of a moderate anaemia in dogs?

Answer 12

18-29%

Question 13

what is the PCV of a severe anaemia in dogs?

Answer 13

<18%

Question 14

what is the PCV of a mild anaemia in cats?

Answer 14

20-24%

Question 15

what is the PCV of a moderate anaemia in cats?

Answer 15

15-19%

Question 16

what is the PCV of a severe anaemia in cats?

Answer 16

<15%

Question 17

what are the ways erythrocyte index can be described?

Answer 17

MCV - mean corpuscular volume
MCHC - mean corpuscular haemoglobin concentration

Question 18

what are findings on haematology of regenerative anaemia?

Answer 18

reticulocytosis
polychromasia

Question 19

what is reticulocytosis?

Answer 19

increased levels of reticulocytes

Question 20

how can polychromatophils be visualised?

Answer 20

staining with diff quik

Question 21

how can reticulocytes be visualised?

Answer 21

stain with new methylene blue

Question 22

how long does it take for reticulocytes to increase following the onset of anaemia?

Answer 22

2-3 days (all anaemias appear non-regenerative initially)

Question 23

when do reticulocyte levels peak following onset of anaemia?

Answer 23

4-7 days

Question 24

what are the two types of feline reticulocytes?

Answer 24

aggregate
punctate

Question 25

what are the stages of mature red blood cell formation in cats?

Answer 25

nucleated red blood cell aggregate reticulocytes punctate reticulocytes mature red blood cells

Question 26

how long do feline aggregate reticulocytes last for?

Answer 26

24 hours

Question 27

how do patients with hypovolaemic shock present?

Answer 27

pallor tachycardia weak peripheral pulses poor peripheral perfusion and cold extremities

Question 28

what causes hypovolaemic shock?

Answer 28

acute haemorrhage

Question 29

how is chronic blood loss defined?

Answer 29

bleeding for >2 weeks

Question 30

what type of anaemia can be caused by chronic blood loss?

Answer 30

iron deficiency anaemia

Question 31

how long to adult patients have to have chronic haemorrhage for to develop iron deficiency anaemia?

Answer 31

over a month

Question 32

how is iron deficiency anaemia initially described?

Answer 32

regenerative (will then turn non-regenerative as the iron depletes)

Question 33

how do red blood cells appear in cases of iron deficiency anaemia appear?

Answer 33

microcytic hypochromic

Question 34

what is the most common cause of iron deficiency anaemia?

Answer 34

chronic bleeding (typically GI)

Question 35

what is the usually cause of chronic bleeding resulting in iron deficiency anaemia?

Answer 35

GI - NSAIDs, steroids, neoplasia, ulcers

Question 36

what can cause chronic bleeding which may result in iron deficiency anaemia?

Answer 36

body system haemorrhage congenital haemostatic defects parasitic infestations (diet is rare but seen in puppies/kittens with vegan diets)

Question 37

how is iron deficiency anaemia treated?

Answer 37

determine underlying cause iron supplementation blood/packed red cell transfusion

Question 38

what iron supplements are available for iron deficiency anaemia?

Answer 38

oral ferrous sulphate iron dextran (possible anaphylaxis)

Question 39

what are the two categories of haemolysis?

Answer 39

immune-mediated non-immune-mediated

Question 40

what are some non-immune mediated causes of haemolysis?

Answer 40

oxidative damage (onions, paracetamol, zinc) intra-erythrocytic parasites mechanical damage

Question 41

what is the process of extravascular haemolysis?

Answer 41

antibody binds to RBC macrophage recognises RBC RBC undergoes phagocytosis haem converted to bilirubin

Question 42

what happens to the ham released from extravascular haemolysis?

Answer 42

converted to bilirubin which is conjugated by the liver and excreted in bile

Question 43

what are the clinical signs of extravascular haemolysis?

Answer 43

pallor lethargy tachycardia, tachypnoea splenomegaly jaundice

Question 44

what happens to free haemoglobin after intravascular haemolysis?

Answer 44

excreted in urine (haemoglobinuria) processed by liver

Question 45

what are the two main categories of haemolysis?

Answer 45

intravascular extravascular

Question 46

what is a consequence of haemoglobinuria?

Answer 46

renal compromise from tubular epithelial damage (toxic nephrosis )

Question 47

what are the clinical signs of intravascular haemolysis?

Answer 47

sudden onset (severe) pallor collapse jaundice tachycardia, tachypnoea splenomegaly haemoglobinuria

Question 48

what are signs of immune mediadiated haemolytic anaemia on haematology?

Answer 48

regenerative anaemia (not always) autoagglutination spherocytes leukocytosis (with left shift)

Question 49

why might patients with immune mediated haemolytic anaemia present with poorly regenerative anaemia?

Answer 49

acute onset (pre-regeneration) immune-targeting of RBC precursors

Question 50

how do spherocytes for?

Answer 50

partially phagocytose RBCs lose their cell membrane which leads to the loss of the discoid shape of the cell (spherocyte)

Question 51

what does finding spherocytes on haematology strongly suggest?

Answer 51

the animals has IMHA (immune mediated haemolytic anaemia)

Question 52

where should you look for spherocytes on a blood smear?

Answer 52

around the monolayer

Question 53

what is autoagglutination?

Answer 53

antibody mediated clumping of red blood cells

Question 54

what causes autoagglutination?

Answer 54

antierythrocyte IgM

Question 55

what are rouleaux bodies?

Answer 55

stacking of RBCs due to increased plasma proteins coating RBCs caused by inflammation (cancer)

Question 56

what animals are rouleaux formations seen as normal?

Answer 56

horses and cats

Question 57

how can you test if you are seeing a rouleaux or agglutination?

Answer 57

wash anti coagulated blood with saline and the rouleaux will disappear

Question 58

what is the Coombs test used for?

Answer 58

detect presence of anti-erythrocyte antibodies and complement on RBCs

Question 59

when can the Coombs test not be used?

Answer 59

if agglutination is already present

Question 60

what are the two types of immune-mediated haemolytic anaemia?

Answer 60

primary secondary

Question 61

what can be some possible triggers for secondary IMHA?

Answer 61

drugs, vaccines, infectious disease, inflammatory disease, neoplasia

Question 62

what tests could be done if you are suspicious of DIC?

Answer 62

PT or d-dimers

Question 63

what changes would be seen on biochemistry of animals with IMHA?

Answer 63

elevated ALT and ALP hyperbilirubinaemia possible azotaemia

Question 64

what changes would be seen on urinalysis of an animal with IMHA?

Answer 64

haemoglobinuria bilirubinuria proteinuria