**_🫀🫁Cardio & Resp🫀🫁 - Anaemia Flashcards

1
Q

What abnormalities can be seen in this blood film?

A

Spherocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Liver function tests show bilirubin of 30μmol/l (normal range <17), and the bilirubin was mainly unconjugated.
What does this tell us?

A

Pre-hepatic jaundice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

High unconjugated bilirubin, and spherocytes on the blood film. What does this tell us?

A

Hereditary spherocytosis, leading to jaundice due to increased destruction in the spleen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What will also be seen in the blood of someone with increased erythrocyte destruction?

A

High reticulocyte (immature RBC) count

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How are reticulocytes identifiable on a blood film?

A

Slightly larger with a bluish tinge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What causes the bluish tinge in reticulocytes?

A

Higher RNA content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does spherocytosis occur?

A

Disruption of vertical linkages in membrane
Usually ankyrin/spectrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens due to hereditary spherocytosis?

A

Haemolysis or haemolytic anaemia
Can result in jaundice
Increase in bone marrow production - leads to young cells found in blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the difference between haemolysis and haemolytic anaemia?

A

Haemolysis is increased RBC destruction (reduced RBC survival)
Haemolytic anaemia is haemolysis that can’t be compensated for - leads to reduction in Hb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How would someone with haemolytic anaemia by treated?

A

Folic acid (because of increased erythropoiesis demand)
Splenectomy (if severe) to increased RBC life span

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Patient with hereditary spherocytosis diagnosis presents several years later acutely with upper right abdominal pain and tenderness, marked jaundice and high bilirubin, this time conjugated.
What has happened?

A

Likely gallstones from increased breakdown of haemoglobin to bilirubin
One of the gallstones has obstructed the CBD - obstructive jaundice
Is post hepatic - hence conjugated bilirubin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is AIHA?

A

Autoimmune haemolytic anaemia
Usually found in multi-system autoimmune conditions (e.g. SLE)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What would you see in AIHA blood count?

A

Low Hb (increased RBC destruction)
High MCV (reticulocytes)
Increased reticulocyte count
High bilirubin
LDH - due to tissue damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the DAT?

A

Direct antiglobulin test
Tests for antibodies that bind to RBCs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the mechanism of RBC destruction in AIHA?

A

Autoantibodies bind to RBCs
Results in destruction in the spleen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Spherocytes are present in which two blood disorders?

A

Hereditary spherocytosis
AIHA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What test can distinguish between hereditary spherocytosis and AIHA?

A

DAT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the most common enzyme deficiency that results in anaemia?

A

G6PD deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does a G6PD deficiency result in for a RBC?

A

Inhibits the pentose shunt
Key process that protects the RBC from oxidant damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does G6PD lead to more oxidative damage being received by a RBC?

A

G6PD deficiency reduces the ability of red blood cells to regenerate glutathione, a critical antioxidant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What type of jaundice will be exhibited in someone with G6PD deficiency?

A

Pre-hepatic jaundice
Unconjugated bilirubin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What would you expect to see in the blood count of someone with anaemia caused by G6PD deficiency?

A

Low Hb
High MCV
High reticulocytes
Classic haemolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What will you see in the blood film of someone with G6PD deficiency?

A

Ghost cells
Heinz body
Hemighosts
(cells with haemoglobin abnormalities due to oxidising damage)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What advice should be given to patients with G6PD?

A

Avoid oxidant drugs
Don’t eat broad beans (fava beans)
Avoid napthalene
Be aware that haemolysis can result from infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How can haemolytic anaemia be categorised?

A

Haemolysis can result from an intrinsic abnormality of the red cells
Haemolysis can result from extrinsic factors acting on normal red cells
ALTERNATIVELY
Inherited haemolytic anaemia can result from abnormalities in the
cell membrane, the haemoglobin or the enzymes in the red cell
Acquired haemolytic anaemia usually results from extrinsic factors
such as micro-organisms, chemicals or drugs that damage the red cell
Extrinsic factors can interact with red cells that have an intrinsic
abnormality

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How can haemolytic anaemia be classified in terms of vascularity?

A

Intravascular haemolysis - occurs when there is acute damage to the RBC
Extravascular haemolysis - defective RBCs removed by the spleen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What general things would you be looking for in haemolytic anaemia?

A

Otherwise unexplained anaemia, normochromic and either normocytic or macrocytic
Evidence of morphologically abnormal red cells
Evidence of increased red cell breakdown
Evidence of increased bone marrow activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Give a summary of the inherited haemolytic anaemias

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Give a summary of the acquired haemolytic anaemias

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Would would you expect to see in the blood count of someone with iron deficiency anaemia?

A

Low Hb
Low MCV (microcytic anaemia)
Low MCH and MCHC
Low RBC
High platelets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What extra tests would you request if you suspected microcytic anaemia (due to iron deficiency)?

A

Ferritin
Serum iron
Transferrin

32
Q

What questions would you ask a patient suspected of having iron deficiency anaemia?

A

Diet - vegetarian/vegan
GI symptoms
Menstrual history/post-menopausal bleeding
Weight loss
Medications - e.g. aspirin/NSAIDs

33
Q

What clinical signs might you see in iron deficiency anaemia?

A
34
Q

What investigations would you send for in someone suspected of iron deficiency anaemia?

A

Investigating for blood in stool (faecal immunochemical test, FIT)
GI investigations - endoscopy, duodenal biopsies, colonoscopy
Coeliac antibody testing

35
Q

What would you expect to see in a blood film of someone with iron deficiency anaemia?

A

Elliptocytes are the feature you would be looking for, more than target cells

36
Q

What are the causes of iron deficiency anaemia?

A

Increased loss (from blood loss)
Insufficient iron intake
Increased iron requirements

37
Q

In what scenarios would blood loss cause iron deficiency anaemia?

A

Commonest cause in adults
Hookworm commonest cause worldwide
Menstrual (menorrhagia)
Gastrointestinal (often occult)

38
Q

How might insufficient iron intake arise?

A

Dietary - vegetarians/vegans
Malabsorption
-Coeliac disease
-H. pylori gastritis

39
Q

What can lead to increased iron requirements

A

Physiological
-Pregnancy
-Infancy

40
Q

Why is transferrin high in iron deficiency anaemia?

A

Increase iron absorption capabilities
Compensatory mechanism

41
Q

Why is there reduced ferritin in iron deficiency anaemia?

A

Attempt to increase iron supply
Reduced hepcidin production - leads to increased iron absorption in gut and release of storage iron

42
Q

What is the treatment for iron deficiency anaemia?

A

Iron replacement therapy
e.g. ferrous sulphate tablets

43
Q

What type of anaemia would accompany a case of, for example, sever rheumatoid arthritis for many years?

A

Anaemia of chronic disease

44
Q

What would you expect to see in the MCV in anaemia of chronic disease?

A

Decrease
Microcytic anaemia

45
Q

What would the reticulocyte levels look like in anaemia of chronic disease?

A

Normal

46
Q

What profile of results would you expect to see in the blood test of someone with anaemia of chronic disease?

A

High ferritin
Low serum iron
Low transferrin
Normal transferrin saturation
High ESR
Hypochromic, microcytic red blood cells

47
Q

Explain the significance of the blood test results of someone with anaemia of chronic disease

A

High ESR - ongoing inflammatory or chronic disease process, as inflammation increases fibrinogen and other acute-phase proteins
Ferritin is an acute-phase reactant that is elevated in inflammatory states
Low serum iron - reduced availability of iron for erythropoiesis - due to sequestration of iron by macrophages
Transferrin levels reduced in ACD - liver reduces its production in response to inflammation
Transferrin Saturation: Normal - iron and transferrin are lowered in proportion

48
Q

What is ferritin, and what is it’s significance in ACD?

A

Storage protein for iron
In ACD, ferritin is elevated due to its role as an acute-phase reactant, even though the body has functionally low iron available for red blood cell production

49
Q

What is transferrin, and what is it’s significance in ACD?

A

Protein responsible for transporting iron in the bloodstream
In ACD, transferrin levels are low due to reduced hepatic production during inflammation, limiting iron mobilization

50
Q

What is ESR, and what is it’s significance in ACD?

A

ESR measures the rate at which erythrocytes sediment in a test tube over one hour, reflecting inflammation
Elevated ESR indicates a chronic inflammatory or autoimmune process contributing to the anaemia

51
Q

How would two people with ACD and iron deficiency anaemia’s blood tests compare?

A
52
Q

What is the basic mechanism of ACD?

A

Hepcidin is usually secreted by the liver in response to high iron stores
Hepcidin production is also increased in inflammatory states (ACD results from a prolonged inflammatory state i.e. chronic disease)
This reduces iron supply as hepcidin blocks absorption of iron from the gut and release of storage iron

53
Q

How is ACD treated?

A

Underlying cause must be treated

54
Q

What is pernicious anaemia?

A

Anaemia caused by a deficiency of vitamin B12
SPECIFICALLY due to autoimmune destruction of intrinsic factor
i.e. vitamin B12 deficiency anaemia

55
Q

What would you expect to see in the blood tests of someone with B12 deficiency leading to anaemia?

A

High MCV - macrocytic anaemia
Low WBC - ineffective haematopoiesis
Low platelets - suggest bone marrow involvement - problem lies in haematopoiesis
Normal reticulocytes - bone marrow unable to respond to the anaemia
High LDH - increased cell turnover and haemolysis
Unconjugated bilirubin increased - increased haemolysis

56
Q

Why might patients with B12 deficiency describe “walking on cotton wool” or other physical sensation disturbances?

A

Vitamin B12 deficiency can lead to neuropathy - demyelination of peripheral nerves and spinal cord

57
Q

What would you see in the blood film and bone marrow aspirate of someone with B12 deficiency?

A

Macrocytosis, poikilocytosis (irregularly shaped RBCs) and hypersegmented neutrophils
Megaloblastic changes (large, immature, nucleated red cell precursors) - suggests impaired DNA synthesis

58
Q

How would a normal bone marrow aspirate look compared to a bone marrow aspirate taken from someone with megaloblastic anaemia?

A
59
Q

What are the causes of megaloblastic change in the bone marrow?

A

Vitamin B12 and Folate
-Required for DNA synthesis
-Absence leads to severe anaemia which can
be fatal
-Secondary to agents or mutations that impair
DNA synthesis
-Drugs: azathioprine, cytotoxic chemotherapy
-Folate antagonists: methotrexate
-BM cancers: myelodysplastic syndrome

60
Q

What is vitamin B12 required for?

A

DNA synthesis
Integrity of the nervous system

61
Q

What is folic acid required for?

A

DNA synthesis
Homocysteine metabolism

62
Q

Outline dietary B12 deficiency

A

B12 present in animal products
Deficiency can result from poor diet/veganism
Oral supplementation

63
Q

Outline gastric B12 deficiency

A

Intrinsic factor required for B12 absorption
Deficiency arise after some bariatric procedures (e.g. gastrectomy), or autoimmune conditions (pernicious anaemia)
Treated with hydroxocobalamin injections (IM)

64
Q

Outline B12 deficiency based in the bowels

A

Terminal ileum site of B12 absorption
Crohn’s disease, Ileal resection - things that can effect absorption in the terminal ileum
Treated with hydroxocobalamin injections (IM)

65
Q

What are the 2 main mechanisms behind folic acid deficiency?

A

Reduced availability
Increased demand

66
Q

What are the causes for reduced availability of folic acid?

A

Dietary
-Poverty
-Alcoholism
Malabsorption
-Coeliac disease
-Jejunal resection

67
Q

What are the causes for the increased demand of folic acid?

A

Pregnancy
Lactation
Increased cell turnover - haemolysis

68
Q

How are all forms of folic acid treated?

A

Oral supplementation

69
Q

(Broad review)
What are the 2 primary possible mechanisms of anaemia?

A

RBC failure of production
OR
RBC excess loss/destruction

70
Q

(Broad review)
What are some causes of anaemia due to reduced RBC survival (i.e. excess destruction)?

A

Hereditary spherocytosis, thalassaemias, sickle cell
Autoimmune haemolytic anaemia (AIHA)
G6PD deficiency
(some infections, e.g. malaria)
(hypersplenism)

71
Q

(Broad review)
What are some of the causes of anaemia due to reduced RBC production?

A

Iron deficiency anaemia
Anaemia of chronic disease (ACD)
Megaloblastic anaemia (B12/folic acid deficiency)
Bone marrow disorders (myelodysplastic syndromes (MDS), aplastic anaemia, marrow infiltration by malignancy)
(CKD)
(alcohol and drug (e.g. chemotherapy) induced anaemia)

72
Q

(Broad review)
How can anaemias be classified based on their size?

A
73
Q

(Broad review)
What causes microcytic anaemias?

A

Defect in haem synthesis
-Iron deficiency anaemia
-Anaemia of chronic disease (ACD)
Defect in globin synthesis
-Defect in α chain synthesis (α thalassaemia)
-Defect in β chain synthesis (β thalassaemia)

74
Q

(Broad review)
Outline the mechanisms and causes of normocytic anaemia

A
75
Q

(Broad review)
Outline the common causes of macrocytic anaemia

A
76
Q

(Broad review)
What is megaloblastic anaemia?

A