Anaemia

Question 1

Anaemia associated with decreased production =

Answer 1

Low reticulocyte count

Hypoproliferative anaemia (reduced amount of erythropoiesis)
Maturation defect (erythropoiesis is active but ineffective)
Failure to produce Hb (a cytoplasmic defect)
Failure of cell division (a nuclear defect)

Question 2

Anaemia associated with increased loss/destruction =

Answer 2

High reticulocyte count

Bleeding
Haemolysis

Question 3

Mean cell volume is low (microcytic) =

Answer 3

Haemoglobin cause

Question 4

Mean cell volume is high (macrocytic) =

Answer 4

Problems with cell division i.e. maturation

Question 5

Causes of microcytic anaemias

Answer 5

TAILS

Thalassaemia
Anaemia of chronic disease
Iron deficiency
Lead poisoning
Sideroblastic anaemias (congenital)

Question 6

What does circulating iron bind to ?

Answer 6

Transferrin

(transports iron from donor tissues [macrophages, intestinal cells and hepatocytes] to tissues expressing transferrin receptors - especially erythroid marrow)

Question 7

How to measure iron supply

Answer 7

% saturation of transferrin with iron

• reduced in iron deficiency
• reduced in anaemia of chronic disease
• increased in genetic haemochromatosis

Question 8

Why is serum ferritin measured ?

Answer 8

Indirect measure of storage iron

Low ferritin = low iron

Question 9

How iron is stored:

Answer 9

Question 10

Iron supplement given to children ?

Answer 10

Sodium feredetate (sytron) - liquid prep with lower elemental iron concentration

Question 11

Low Hb, low RBC, high MCV

Question 12

What happens as normoblasts (red cell precursors) develop?

Answer 12

• Accumulate Hb
• Reduce in cell and nuclear size as the nucleus matures
• Stop dividing and lose nucleus (Hb content triggers this)

Question 13

What happens in megaloblastic anaemia?

Answer 13

Larger precursor cells with an immature nucleus

They accumulate Hb - but there is a smaller number of macrocytes - therefore ANAEMIA

Question 14

Causes of megaloblastic anaemia ?

Answer 14

B12 deficiency
Folate deficiency
Drugs
Rare inherited abnormalities

Question 15

What causes pernicious anaemia ?

Answer 15

Autoimmune condition with resulting destruction of gastric parietal cells

• results in intrinsic factor deficiency with B12 malabsorption and deficiency

Question 16

B12/Folate deficiency symptoms

Answer 16

Symptoms/signs of anaemia
weight loss, diarrhoea, infertility
Sore tongue, jaundice
Developmental problems

+ B12 only: Neurological problems

Question 17

Pernicious anaemia treatment

Answer 17

Vitamin B12 (hydroxycobalamin) injections for life

Question 18

Causes of non-megaloblastic anaemia

Answer 18

• Alcohol
• Liver disease
• Hypothyroidism
• Marrow failure: Myelodysplasia, Myeloma, Aplastic anaemia

Question 19

Why are people with pernicious anaemia mildly jaundiced ?

Answer 19

• Red cells die prematurely in the marrow
• Haemoglobin and lactate dehydrogenase (LDH) are released from dead red cells
• Haemoglobin converted to bilirubin

Question 20

• High reticulocyte count
• Increased unconjugated serum bilirubin
• Increased urinary urobilinogen
• Splenomegaly

Answer 20

Haemolysis

Question 21

Microcytic anaemia differential diagnosis

Answer 21

TAILS

Thalassaemia
Anaemia of chronic disease
Iron defiency
Lead poisoning
Sideroblastic anaemia

Question 22

Physiology of EPO

Answer 22

Kidneys detect reduced O2
EPO secreted into blood
EPO stimulates erythropoiesis by bone marrow
Additional circulating erythrocytes improve O2 carrying

Question 23

Role of hepcidin

Answer 23

Regulates ferroportin (the iron exporter)

Binds to ferroportin - breaks down ferroportin - therefore iron can’t be exported from iron storage

Question 24

Where is hepcidin synthesised?

Answer 24

Primarily hepatocytes (liver)

Question 25

Ferritin levels in anaemia of chronic disease ?

Answer 25

Normal or increased

Question 26

Ferritin levels in iron deficiency ?

Answer 26

Low

Question 27

Excess alcohol = micro/macrocytosis?

Answer 27

Mild macrocytosis

Question 28

MCV > 120fl = (usually)

Answer 28

B12 or Folate deficiency

Question 29

Hypersegmented neutrophils + oval macrocytes on blood film =

Answer 29

Megaloblastic

Question 30

Dysplastic neutrophils on blood film =

Answer 30

Myelodysplasia

Question 31

Uniform macrocytosis on blood film =

Answer 31

Alcohol

Question 32

Malabsorption of iron is primarily in ______

Answer 32

Jejunum

Question 33

Iron deficiency over 50 y.o. - what investigations must be done ?

Answer 33

GI investigations for malignancy even with negative FOBs (foetal occult blood tests)

Question 34

Macrocytic anaemia causes =

Answer 34

FAT RBC Foetus Alcohol Thyroid Reticulocytosis - acute blood loss OR haemolysis B12 + Folate deficiencies Cirrhosis/chronic liver disease

Question 35

Explain why TAILS conditions cause reduced MCV

Answer 35

T = Globin (imbalanced ratio of globin chains, Unbound globin chains precipitate, leading to the destruction of erythroid precursors) A = depends I = iron L = inhibits ferrochelatase (used in haem synthesis) S = inhibits mitochondrial proteins which regulate protoporphyrin (and therefore haem) synthesis

Question 36

When is IV iron prescribed?

Answer 36

When rapid iron replacement is needed e.g. 3rd trimester of pregnancy, before surgery Malabsorption

Question 37

Reticulocytosis could be due to either...

Answer 37

1. Acute blood loss or 2. Haemolysis

Question 38

Blood film for B12/Folate deficiency =

Answer 38

Macroovalocytes + hypersegmented neutrophils in megaloblastic anaemia

Question 39

Why does reticulocytosis cause increased MCV?

Answer 39

Reticulocytes are immature and therefore larger So this is a "pseudomacrocytosis" as the RBCs haven't actually increased MCV

Question 40

Reticulocytosis appearance on blood film

Answer 40

Polychromasia !!

Question 41

What do the red arrows indicate?

Answer 41

Spherocytes - indicate haemolysis - indicated by raised MCHC (mean corpuscular haemoglobin concentration)

Question 42

Spherocytes are...

Answer 42

Red blood cells with no central pallor due to membrane damage seen in haemolysis

Question 43

LFT which shows liver synthesis levels ?

Answer 43

Albumin

Question 44

LFT which shows haemoglobin breakdown (haemolysis)

Answer 44

Bilirubins

Question 45

What does raised lactate dehydrogenase indicate?

Answer 45

Non-specific cell damage/necrosis

Question 46

What does reduced haptoglobulin indicate?

Answer 46

Haemolytic anaemia (protein which binds to free haemoglobin released from lysed red cells)

Question 47

When to suspect haemolytic anaemia?

Answer 47

Reticulocytosis (high ret count, anaemia with polychromasia) = either haemolysis or acute blood loss Chronic blood loss = microcytosis, iron deficiency, no reticulocytosis Spherocytes - cells with no central pallor due to membrane damage in haemolysis

Question 48

Other name for DAT (Direct Antibody Test)

Answer 48

Coombs test

Question 49

Management of autoimmune haemolysis =

Answer 49

Steroids + folic acid