1b Anaemia and Transfusion Flashcards

1
Q

How do we interpret an increase in unconjugated bilirubin?

A

Unconjugated hyperbilirubinemia is caused byproblems with red blood cell stability and survival or by defects in the bilirubin-conjugating enzyme, UGT.

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

How do we interpret an increase in conjugated bilirubin?

A

In contrast, disorders that result in conjugated hyperbilirubinemia are usually caused by intrinsic liver dysfunction

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

What is seen on a blood film in a patient with raised unconjugated bilirubin?

A

Round cells that lack central pallor = spherocytes
polychromatic MACROCYTES
high reticulocyte count

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

What causes hereditary spherocytosis?

A

Disruption of vertical linkages in the membrane, usually due to ankyrin/spectrin

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

What causes high reticulocytes?

A

Reticulocytosis can be a key indicator that the bone marrow is responding to a need for increased red blood cell production. Causes include anaemia,compensated blood loss or hemolysis and hypoxia

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

How does the bone marrow respond to haemolytic anaemia?

A

Reticulocytosis - immature red blood cells enter into circulation which then form reticulocytes, and can lead to polychromasia

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

What is polychromasia?

A

Polychromasia is thepresentation of multicolored red blood cells in a blood smear test. It’s an indication of red blood cells being released prematurely from bone marrow during formation.

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

Why is there colour seen on the red blood cells in polychromasia?

A

ribosomes still left on the immature blood cells, which are not found on mature red blood cells. These cells still contain a nucleus with genetic material as well due to the early release, which is not needed in mature blood cells because their only function is to carry oxygen in the blood.

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

What is haemolytic anaemia?

A

Increased destruction with shortened RBC survival and resultant anaemia = haemolysis which leads to a reduction in Hb

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

What is the treatment for haemolytic anaemia?

A

Folic Acid (because of the increased need)
Splenectomy (to increase the life span of the red blood cells
Vb12

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

What is the major consequence of haemolytic anaemia?

A

Gallstones

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

What are the symptoms of gallstones which might present in a patient with haemolytic anaemia?

A

Upper abdominal pain
Tenderness
Jaundice - due to elevated conjugated bilirubin

The gallstones cause obstructive jaundice

Liver is still able to conjugate the bilirubin but it isnt passing from the bile ducts and gall bladder into the duodenum

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

What type of stones do patients with haemolytic anaemia get?

A

Pigment stones

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

What are the two possible causes of anaemia?

A

RBC failure of production

RBC excess loss / destruction

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

What are some of the effects of SLE?

A

Autoimmune

  • Polyarthritis
  • Renal impairment
  • Facial skin rashes
  • Hepatitis
  • Tiredness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are some of the changes seen to the blood cells when a patient has SLE?

A

Low HB = anaemia
High MCV = macrocytic

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

What is DAT?

A

Direct anti-globulin test = antibodies that bind to antigens on the erythrocyte membrane in a patient who has developed an auto-antibody

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

What is DAT used to do?

A

Confirm the presence of autoimmune haemolytic anaemia

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

What is AIHA?

A

Auto-immune haemolytic anaemia

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

What is AIHA associated with?

A

Disorders of the immune system = SLE and lymphoma

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

Outline 4 laboratory evidence of haemolysis?

A

LDH raised
Unconjugated bilirubin
Reduced haptoglobin
Reticulocytosis

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

Why is raised LDH a sign of hameolysis?

A

LDH is present in red cells and hemolysis causes release into the plasma.

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

Why is reduced haptoglobin a sign of haemolysis?

A

Haptoglobin is primarily produced in the liver and is functionally important for binding free hemoglobin from lysed red cells in vivo, preventing its toxic effects. Because haptoglobin levelsbecome depleted inthe presence of large amounts of free hemoglobin, decreased haptoglobin is a marker of hemolysis.

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

What are the 2 categories of haemolytic anaemia?

A
  1. Inherited(RBC defect)
  2. Acquired (RBC environment defect/plasma/vasculature)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Which two conditions are spherocytes present in and what test is used to differentiate between them?
Hereditary spherocytosis Acquired auto-immune haemolysic anaemia DAT test = positive in AIHA
26
What environmental factors can cause non-immune haemolysis?
Microangiopathic Malaria Snake venom Drugs
27
What pathway provides energy for the cell?
Glycolytic pathway
28
Which shuttle protects the glycolytic pathway from oxidant damage?
Pentose shunt
29
What enzyme is key in the pentose shunt?
G6PD
30
What is G6PD
Glucose-6-phosphate deficiency
31
What is the HMP shunt tightly coupled to?
The metabolism of glutathione - protects from oxidant damage
32
Why is G6PD deficiency a problem?
Makes the red cells susceptible to oxidant damage= resulting in haemolysis
33
What blood cell type shows oxidant damage to the red cell?
Irregularly contacted cells and Heinz Bodies, Ghost cells
34
What are Heinz Bodies
= precipitated oxidised haemoglobin
35
What do the prescence of ghost cells show?
intravascular haemolysis
36
What advice would you give to a patient with G6PD Deficiency?
Avoid oxidant drugs Dont eat broad beans Avoid Naphthalene be aware that haemolysis can arise from infection
37
A patient is feeling tired, lethargic, breathless at rest which gets worse on exertion, ankle swelling at end of day. Blood count is as follows:
Low Hb Low MCV- microcytic Low MCH and MCHC- hypochromic Thrombocytosis Low ferritin high transferrin and TIBC + low transferring sat
38
How to differentiate between thalassamia and iron deficiency anaemia?
Hb electrophoresis- no high A2 so not thalassaemia
39
What are the clinical symptoms of iron deficiency anaemia
Koilonychia - spoon nails Glossitis Angular Stomatitis
40
What investigations might be done on a patient who has weight loss but no other symptoms?
Investigate for blood in the stool - FIT GI Investigations - Upper GI endoscopy - oesophagus, stomach and duodenum
41
What are the causes of iron deficiency?
Menstrual Pregnancy lactation Vegan Malnutrition Vitamin C defiency
42
What is seen on a blood film with patients who have iron defiency?
Small cells = microcytosis due to low MCV Pale cells = hypochromia due to low MCHC Target cells pencil cells = elliptocytes
43
What are the differential diagnosis of anaemia associated with a low MCV (microcytic anaemia)?
Iron deficiency anaemia Thalassaemia Anaemia of chronic disease
44
How is iron deficiency of anaemia treated?
Iron deficiency anemia is usually treated in two ways, which involve increasing iron intake and treating any underlying conditions
45
What is the difference between intravascular and extra-vascular haemolysis?
Intra = acute damage to the RBC Extra = removed by the spleen
46
What type of haemolytic anaemia results from a mechanical problem with the entire red blood cell?
Microangiopathic haemolytic anaemia (MAHA)
47
How is iron deficient anaemia treated?
Iron replacement therapy = ferrous sulphate tablets
48
What happens when ferritin is low?
reduced hepcidin production Increases iron supply
49
What happens to ferritin when transferritin is raised?
Ferritin is low
50
What happens to iron absorption when hepcidin is lowered?
Absorption of iron from the gut and release of storage iron are increased
51
What is ferritin and what is the significance of this test?
Ferritin is a universal intracellular protein that stores iron and releases it in a controlled fashion. Produced in liver.
52
What does a low ferritin indicate?
If a ferritin test reveals that your blood ferritin level is lower than normal, it indicates your body's iron stores are low and you have iron deficiency.
53
What is transferrin and what is the significance of this test?
Transferrin is a blood-plasma glycoprotein, which plays a central role in iron metabolism and is responsible for ferric-ion delivery.
54
What does high and low transferritin indicate?
If it is low, it means a great proportion of it is bound to iron and little free transferrin is available If it is high, it means a lot of it is unbound to iron⇒ iron deficiency anaemia
55
What is ESR and what is the significance of this test?
An ESR (erythrocyte sedimentation rate test) is a blood test that helps detect inflammation from autoimmune diseases, infection, cancer, and more.
56
What does a high ESR indicate?
Anaemia of chronic disease
57
Describe the pathophysiology of ACD.
Pro inflammatory cytokines reduce EPO production and upregulate hepcidin. This will reduce RBC production (low EPO), and will reduce FE absorption, transport and availability (low hepcidin), which will inhibit cell growth and maturation
58
Which pro-inflammatory cytokines are activated in ACD?
IL-1 TNF-alpha IL-6
59
Which organs is high iron toxic to?
Heart and liver
60
How is anaemia of Chronic Disease treated?
By treating the underlying disease
61
What is frequently seen in a blood film with patients who have megaloblastic anaemia?
Hypersegmented neutrophils Poikilocytosis megaloblasts LOW HB HIGH MCV- MACROCYTIC LOW PLATELETS, WBC HIGH LDH + UNCONJUGATED BILIRUBIN (HAEMOLYSIS)
62
What can cause megaloblastic anaemia?
Vitamin B12 / folate deficiency
63
What are megaloblasts?
Large cells with nucleocytoplasmic dissociation Impaired DNA synthesis, nuclear maturation and cell division
64
Why does folate and B12 deficiency lead to megaloblastic anaemia?
needed for dTTP synthesis which is needed to make thymidine which is needed for DNA synthesis = therefore cannot make DNA, and nuclear maturation cannot occur deficiency but cells cannot divide but continue to grow = macrocytosis
65
Which drugs can cause megaloblastic changes?
Aziothioprine Cytotoxic chemo Folate antagonists = methotrexate
66
What is pernicious anaemia?
lack of IF - therefore B12 cannot be absorbed, therefore megaloblastic anaemia
67
How is folic acid deficiency treated?
oral supplements
68
What are the common causes of microcytic anaemia?
Defect in haem synthesis and defe5t in globin synthesis
69
Which two conditions are a result if a defect in haem synthesis?
iron deficiency anaemia and anaemia of chronic disease
70
What is the only blood test result which is high in iron deficiency anaemia?
Transferrin
71
What are the mechanisms of normocytic anaemia?
Recent blood loss failure of production of red cells Pooling of red blood cells in the spleen
72
What is a reason the MVC might be raised?
reticulocytosis as younger cells are larger than older cells
73
What is a megaloblast?
An abnormal erythrocyte in the bone marrow
74
What are the three characteristic changes seen on a blood film in patients with megaloblastic anaemia?
Tear drop cells hypersegmented neutrophils oval macrocytes
75
How to treat dietary Vitamin B12 deficiency?
Oral supplements
76
How to treat Intrinsic Factor Deficiencies which leads to Vitamin B12 defiency?
Hydroxocobalamin Injections
77
What might be some gastric causes of Vitamin B12 deficiency?
Gastrectomy, so less IF can bind Autoimmune = Pernicious Anaemia (Where you have anti-gastric parietal cells and IF antibodies)
78
What are some bowel related causes of vitamin B12 defiency?
Crohn's disease Ileal Resection treat with hydroxocobalamin injections (IM)
79
What are the neurological requirements of folic acid and vitamin B12?
needed for the development of the neural tube, can lead to defects SACD - Sub-acute combined degenration of the spinal cord
80
What is the difference between intravascular and extra-vascular haemolysis?
Intra = acute damage to the RBC Extra = removed by the spleen
81
What are some of the effects of SLE?
Autoimmune - Polyarthritis - Renal impairment - Facial skin rashes - Hepatitis - Tiredness