Haemolysis

Question 1

what is haemolysis

Answer 1

premature red ell destruction ie shortened red cell survival

Question 2

what is compensated haemolysis

Answer 2

increased red cell destruction compensated by increased red cell production ie Hb maintained

Question 3

what are the consequences of haemolysis

Answer 3

erythroid hyperplasia (increae red cell production) 
excess bilirubin

Question 4

what is the bone marrow response to haemolysis

Answer 4

reticulocytosis

erythroid hyperplasia

Question 5

what do reticulocytes show on staining

Answer 5

supravital stain staining ribosomal RNA-new methylene blue

Question 6

how are reticulocytes measured

Answer 6

automated reticulocyte counting

ribosomal RNA is labelled with a fluorochrome and fluorescent cells are counted

Question 7

how can haemolysis be classified

Answer 7

extravascular and intravascular

Question 8

what does extravascular mean

Answer 8

taken up by reticulendothelial system (spleen and liver)

Question 9

what does intravascular mean

Answer 9

red cells destroyed within the circulation

Question 10

in terms of products what does extravasucalr red cell destruction produce

Answer 10

normal products in excess

Question 11

in terms of produces what does intravascular haemolysis produce

Answer 11

abnormal products

Question 12

what does intravascular produce

Answer 12

haemoglobinaemia
methaemalbuminaemia
haemoglobinuria
haemosiderinuria

Question 13

what does haemoglobinuria do

Answer 13

pink urine, turns black on standing

Question 14

what does extravascular release

Answer 14

protoporphyrin

Question 15

does extravascular cause a conjugated or unconjugated bilirubinaemia

Answer 15

unconjugated

Question 16

what can intravascular be caused by

Answer 16

ABO incompatibile blood transfusion
G6PD deficiency
sever falciparum malaria-Blackwater fever

Question 17

what investigations would you do to confirm the haemolytic state

Answer 17

FBC (+ BLOOD Film)
reticulocyte count 
serum unconjugated bilirubin 
serum haptoglobins 
urinary urobilinogen

Question 18

how else can it be classified-by site of red cell defect which are

Answer 18

premature destruction of normal red cells
abnormal cell membrane
abnormal red cell metabolism
abnormal haemoglobin

Question 19

causes of haemolysis acquired

Answer 19

immune
autoimmune haemolysis
alloimmune haemolysis

Question 20

what are some of the causes of warm autoantibody

Answer 20

autoimmune disorders (SLE)
lympohoproliferative
drugs (penicillins), infections

Question 21

what immunoglobulin causes warm autoantibodies

Answer 21

IgG

Question 22

what immunoglobulin causes cold antibodies

Answer 22

IgM

Question 23

what causes cold autoimmune haemolysis

Answer 23

infections (EBV, mycoplasma) , lymphoproliferative disorders

Question 24

describe the direct Coomb’s test

Answer 24

patients RBC are coater with IgG and complement and added to mouse anti-human IgG to see if agglutination occurs

Question 25

what does Direct Coombs identify

Answer 25

antibody and complement bound to own red cells

Question 26

what is alloimmune haemolysis caused by

Answer 26

immune response to antibody produced or passive transfer of antibody

Question 27

causes of antibody produced alloimmune haemolysis

Answer 27

haemolytic transfusion reaction

Question 28

an immediated haemolytic transfusion reaction is intravascular or extravascular

Answer 28

intravascular IgM

Question 29

a delayed haemolytic transfusion reaction is caused by

Answer 29

delayed IgG predominantly extravascular

Question 30

when does passive transfer of antibody occur

Answer 30

in haemolytic disease of the newborn

Question 31

causes of acquired haemolysis

Answer 31

mechanical red cell destruction-DIC, HUS TTP leaking heart valve infections eg malaria

Question 32

what does MAHA stand for and when does it occur

Answer 32

microangiopathic haemolytic anaemia (MAHA) result of mechanical damage

Question 33

what type of cells do you get in burns related haemolysis

Answer 33

microspherocytes

Question 34

why do you get microspherocytes in burns

Answer 34

red cells are sheard as they are passed through the damaged capillaries

Question 35

name some acquired membrane defects

Answer 35

these are all v rare-liver disease (Zieve's syndrome), vitamin E deficiency, paroxysmal nocturnal hameoglobinuria

Question 36

what does Zieves disease look like

Answer 36

anaemia, polychromatic macrocytes, irregularly contracted cells

Question 37

what is Zieves syndrome

Answer 37

haemolysis, alcoholic liver disease, hyperlipidaemia)

Question 38

describe hereditary spherocytosis

Answer 38

reduced membrane deformity increased transit time trough spleen oxidant environment in spleen causes extravascular red cell destruction

Question 39

what can cause genetic abnormal red cell metabolism

Answer 39

failure to cope with oxidant stress (G6PD deficiency) | failure to generate ATP

Question 40

what drug can cause even normal cells to abnormally respond to oxidative stress

Answer 40

dapsone -which can be used to treat leprosy

Question 41

what is a genetic cause of abnormal haemoglobins

Answer 41

sickle cell disease HbS

Question 42

how does sickle cell affect haemoglobin

Answer 42

abnormal polymerisation which results in shortened red cell survivial

Question 43

what is sickle cell caused by

Answer 43

point mutation in B globin chain

Question 44

what signs do you have if you are sickle cell trait

Answer 44

none-asymptomatic

Question 45

Heinz bodies are seen in what type of anaemia

Answer 45

G6PD deficiency