ITS BOARDS

Question 1

define hypo proliferative anaemia

Answer 1

bone marrow contains an inadequate number of red cell precursors (erythroblasts)

Question 2

define ineffective erythropoiesis

Answer 2

despite normal or increased numbers of bone marrow erythroblasts, they produces a reduced number of normal cells

Question 3

define haemolytic/haemorrhagic anaemia

Answer 3

shortened red cell survival

Question 4

what are the most common causes of anaemia

Answer 4

inflammation
iron deficiency
acute bleeding

Question 5

what are less common causes of anaemia

Answer 5

disorders of bone marrow stroma
disorders of stem cells
maturation disorders
haemolytics anaemias

Question 6

when might a bone marrow biopsy aid diagnosis and why

Answer 6

when retic count is low, it may help differentiate between hypo proliferative and maturation disorders

Question 7

why is bone marrow biopsy not indicated if retic count is high

Answer 7

the marrow is clearly capable of producing cells, but they are not surviving normally in circulation

Question 8

in what types of anaemia is the retic count high

Answer 8

haemolytic

haemorrhagic

Question 9

in what types of anaemia is the retic count low

Answer 9

hypoproliferative

maturation disorders

Question 10

what are reticulocytes

Answer 10

young red blood cells that have been formed by extrusion of the erythroblast nucleus

Question 11

why do retics stain slightly blue

Answer 11

they contain RNA/ribosomes

Question 12

what is the normal percentage of retics in blood

Answer 12

1%

Question 13

retic count increases in proportion to

Answer 13

the amount of erythropoiesis in the bone marrow

Question 14

what dye is used to stain reticulocytes

Answer 14

brilliant cresyl blue

Question 15

what is a more accurate measure of red cell production in anaemia; retic percentage or absolute retic count

Answer 15

the absolute retic count

the percentage will be skewed as there is a reduced number of red cells

Question 16

what can cause decreased production of Hb or red cells

Answer 16

iron deficiency anaemia
megaloblastic anaemia
aplastic anaemia

Question 17

what can cause premature loss or destruction of red cells

Answer 17

haemolytic anaemias (autoimmune, inherited red cell defects)
bleeding

Question 18

where is the majority of iron in the body located

Answer 18

in red cells (Hb)

Question 19

what are the three main compartments of body iron

Answer 19

iron stores
transport iron
red cell iron

Question 20

how is iron stored

Answer 20

ferritin

Question 21

how is iron transferred in the plasma and why

Answer 21

transferrin

must be bound to a protein to prevent oxidative damage

Question 22

what is the best measure of iron supply tot tissues

Answer 22

total iron binding capacity

saturation of the serum transferrin

Question 23

how many iron molecules can bind to each transferrin molecule

Answer 23

2

Question 24

what type of iron is present in the diet

Answer 24

ferric (Fe3+)

Question 25

how is iron status assessed

Answer 25

functional iron in red cells (Hb) | storage iron in the form of ferritin

Question 26

what are the levels of iron stores, iron supply to tissues and red cell iron if there is reduced intake or increased loss of iron

Answer 26

iron stores: reduced iron supply to tissues: normal red cell iron: normal

Question 27

what are the levels of iron stores, iron supply to tissues and red cell iron if iron stores are depleted

Answer 27

iron stores: reduced iron supply to tissues: reduced red cell iron: normal

Question 28

what are the levels of iron stores, iron supply to tissues and red cell iron if iron deficient erythropoiesis is occurring

Answer 28

iron stores: reduced iron supply to tissues: reduced red cell iron: reduced

Question 29

what are the common causes of iron deficiency in developing and developed countries

Answer 29

developing countries - blood loss (GI bleeding) - diet developed countries - rapid growth (infants, young children, adolescents) - women of childbearing age (menstrual blood loss, pregnancy)

Question 30

what are the clinical effects of iron deficiency

Answer 30

anaemia epithelial abnormalities impaired lymphocyte function and immune response

Question 31

what epithelial abnormalities are associated with iron deficiency

Answer 31

``` buccal mucosal atrophy gastro mucosal atrophy post cricoid web koilonychia angular cheilitis ```

Question 32

what is the basic structure of Hb

Answer 32

4 globin molecules; 2 alpha, 2 beta 4 haem molecules

Question 33

what mutation causes sickle cell anaemia

Answer 33

substitution of valine for glutamic acid at codon 6 or beta globin gene (point mutation in beta gene)

Question 34

what types of Hb can be produced in homozygotic sickle cell

Answer 34

HbS | variable amount of HbF

Question 35

what causes red cell sickling

Answer 35

intracellular dehydration

Question 36

what is the molecular structure of HbS

Answer 36

a2bs2

Question 37

what are clinical features of sickle cell anaemia

Answer 37

anaemia painful crises rarely aplastic crises, stroke, priapism

Question 38

how do painful crises occur in sickle cell

Answer 38

sickled red cells produce microvascular obstruction and ischaemia crises precipitated by cold, infection, dehydration

Question 39

how many alpha genes are there in each cell

Answer 39

4

Question 40

what genotypes can result in heterozygotic alpha thalassaemia

Answer 40

single gene deletion (a-/aa) two gene deletion (--/aa)

Question 41

what clinical features are present in single/two gene deletion alpha thalassaemia

Answer 41

no clinical features

Question 42

what does a three alpha gene deletion cause

Answer 42

HbH disease with chronic haemolysis

Question 43

what are HbH molecules

Answer 43

beta chan tetramers (ie contain no alpha globin chains)

Question 44

what is hydrops fetalis

Answer 44

four alpha gene deletion | lethal

Question 45

what are signs of heterozygotic beta thalassaemia

Answer 45

high HbA2 low MCV increased red cell count clinically asymptomatic

Question 46

which Hb molecules are present in homozygotic beta thal

Answer 46

no HbA mostly HbF some HbA2

Question 47

what does does precipitation of alpha-globin in erythroid cells produce in beta thal

Answer 47

ineffective erythropoiesis and extra medullary haematopoiesis

Question 48

what is meant by beta thal trait

Answer 48

heterozygotic carriers of the mutation but with no symptoms

Question 49

how are haemoglobin disorders screened for

Answer 49

neonatal: heel prick/cord blood preconceptual: in at risk populations antenatal: selective

Question 50

what are complications of extra medullary haematopoiesis

Answer 50

enlargement of other bones eg maxilla, frontal bossing iron accumulation

Question 51

what are causes of haemolysis

Answer 51

hereditary (enzymatic, membrane disorder, globin disorder) acquired (immune, non-immune)

Question 52

what are causes of immune haemolysis

Answer 52

autoimmune spherocytic alloimmune: haemolytic disease of the newborn ABO mismatch transfusion

Question 53

what are causes of non-immune acquired haemolysis

Answer 53

mechanical (prosthetic heart valve, DIC) infection (malaria) chemical/physical (oxidative stress, burns) membrane: liver disease

Question 54

what are diagnostic tests for haemolysis

Answer 54

direct Coombs test (detects antibodies bound to RBCs) osmotic fragility (increased membrane fragility is spherocytosis) G6PD enzyme activity screening test (quantitates production of NADPH)

Question 55

what are causes of inherited haemolysis

Answer 55

enzymes (G6PD) membrane defects (spherocytosis, ellipocytosis)