Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Year 3 - Haematology (DP) > Red Cell Diseases + Anaemia > Flashcards

Red Cell Diseases + Anaemia Flashcards

1
Q

How long is the average lifespan of a red blood cell?

A

~120 days

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

What is the role of the spleen in red cell homeostasis?

A

Removes fragile old RBCs from circulation

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

What happens to old red blood cells?

A

Phagocytic cells of the liver and spleen engulf old RBCs

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

What are globular Hb proteins broken down to?

A

Amino acids

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

What does iron bind to when haemoglobin is broken down?

A

Transferrin

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

From what cells are proerythroblasts derived from?

A

Myeloid stem cells

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

What cells do proerythroblasts differentiate to?

A

Polychromatic erythroblast

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

What cells are mature erythrocytes differentiated from?

A

Reticulocytes

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

What cells does a polychromatic erythroblast differentiate into?

A

Orthochromatic erythroblast

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

How does a reticulocyte form?

A

Orthochromatic erythroblasts extrude their nucleus leaving only some ribosomal RNA behind

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

What cell stage does Hb first appear in the cytoplasm along the red cell differentiation?

A

Polychromatic erythroblast

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

At what cell stage does the nucleus shrink and the full Hb complement form in the cytoplasm along the red cell differentiation?

A

Orthochromatic erythroblast

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

What is the approximate diameter of a red blood cell?

A

8 micrometres

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

What is the approximate thickness at the edge of a red blood cell?

A

2 micrometres

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

What is the approximate thickness in the centre of a red blood cell?

A

1 micrometre

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

How does the flexible membrane of the red blood cell benefit it?

A

Can deform to allow cells to squeeze in single file through capillaries

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

What is the typical haematocrit in men?

A

40-50%

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

What is the typical haematocrit in women?

A

36-46%

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

What is the packed cell volume composed of?

A

Red blood cells (haematocrit)
“Buffy coat”:
- Platelets
- White blood cells

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

What is the typical RBC count in men?

A

4.5-6.5 x10^12/L

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

What is the typical RBC count in women?

A

3.8-5.8 x10^12/L

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

What ‘pump’ regulates RBC ion balance and cell volume?

A

Energy-dependent Sodium/Potassium ATPases (‘the sodium pump’)

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

What is the only route for ATP synthesis in RBCs and why?

A

Anaerobic glycolysis

Since they have no mitochondria

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

What does NADH gained from glycolysis in RBCs do? Why is this important?

A

Keeps iron in Fe2+ state

Methaemoglobin (HbFe3+) cannot bind oxygen

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

What does the hexose monophosphate shunt in red blood cells do? Why is this important?

A

Produces NADPH

Required for maintenance of adequate levels of reduced glutathione

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

When is 2,3-bisphosphoglycerate produced?

A

When pO2 is reduced

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

What is the purpose of 2,3-bisphosphoglycerate?

A

Releases O2 from Hb

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

What is the structure of glutathione?

A

Tripeptide consisting of:

  • Glutamate
  • Cysteine
  • Glycine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What does reduced glutathione do?

A

Combats oxidative stress

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

What is consumed in the conversion of glucose to glucose-6-phosphate?

A

ATP (to ADP)

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

What enzyme catalyses the conversion of glucose to glucose-6-phosphate?

A

Hexokinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What enzyme catalyses the conversion of glucose-6-phosphate to fructose-6-phosphate?

A

Phosphoglucose isomerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is consumed when fructose-6-phosphate is converted to fructose-1,6-bisphosphonate?

A

ATP (to ADP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What enzyme catalyses the conversion of fructose-6-phosphate to fructose-1,6-bisphosphonate

A

Phosphofructokinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is fructose-1,6-bisphosphonate converted to next in the glycolysis pathway?

A

Glyceraldehyde-3-phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is glyceraldehyde-3-phosphate converted to next in the glycolysis pathway and what conversion occurs alongside this?

A

1,3-bisphosphoglycerate

2NAD+ -> 2NADH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What can 1,3-bisphosphoglycerate be converted to? What does one of these conversions produce?

A

2,3-bisphosphoglycerate
3-phosphoglycerate:
- Producing 2 ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is 3-phosphoglycerate converted to?

A

Phosphoenolpyruvate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is produced when phosphoenolpyruvate is converted to pyruvate?

A

2ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is produced when pyruvate is converted to lactate?

A

NAD+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What does NAD(P)H oxidase xanthine oxidase do?

A

Converts O2 to O2.- (oxygen free radical species)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What does superoxide dismutase do?

A

Converts O2.- to H2O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What do catalase and GSH peroxidase do?

A

Convert H2O2 to H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What does reduced glutathione do?

A

Detoxifies H2O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What else can glucose-6-phosphate be converted to (apart from fructose-6-phosphate)? What is produced and what is consumed?

A

Hexose monophosphates

NADP+ -> NADPH (Consumes GSSG -> GSH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What are pentose phosphates formed from in glycolysis?

A

Hexose monophosphates (Produces NADPH)
Fructose-6-phosphate
Glyceraldehyde-3-phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What enzyme converts glucose-6-phosphate to hexose monophosphates?

A

Glucose-6-phosphate dehydrogenase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What enzyme, alongside NADPH and H+, converts oxidised glutathione to reduced glutathione?

A

Glutathione reductase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What enzyme catalyses the conversion of reduced glutathione to oxidised glutathione? What conversion occurs alongside this?

A

Glutathione peroxidase

H2O2 -> H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What percentage of CO2 is dissolved in the blood?

A

10% (proportional to inhaled pCO2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What percentage of CO2 is bound to Hb? What is it called?

A

30%

Carbaminohaemoblogin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What percentage of CO2 is present in the blood as bicarbonate?

A

60%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What enzyme facilitates CO2 transport in the blood?

A

Carbonic anhydrase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What exchanger facilitates the transport of bicarbonate out of erythrocytes?

A

Bicarbonate/Chloride:

  • Bicarbonate moves out
  • Chloride moves in
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

When fully saturated, how much oxygen will 1g of Hb bind?

A

1.34ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What does haemoglobin synthesis require?

A

Synthesis of globin chains (4 per Hb)
Synthesis of porphyrin ring (haem group)
Insertion of Fe2+ into haem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is the predominant globin structure of foetal Hb?

A

alpha2 gamma2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What happens to the structure of foetal Hb in late gestation?

A

Gamma expression falls

Beta expression rises

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What is the predominant globin structure of adult Hb?

A

alpha2 beta2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What is the normal adult [Hb} in men?

A

130-180g/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is the normal adult [Hb] in women?

A

115-165g/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What does the co-operative behaviour of oxygen binding to Hb mean?

A

Binding of a ligand to one site on the molecule affects the binding of a ligand to a different functional site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What does the steep, venous phase of the haemoglobin oxygen dissociation curve do?

A

Favours O2 off-loading to tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What does the plateau, arterial phase of the haemoglobin oxygen dissociation curve do?

A

Sustains SaO2 >90% over wide range of inspired pO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Does foetal Hb have a lower or higher affinity for oxygen than adult Hb?

A

Higher

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Does foetal Hb have a lower or higher affinity for 2,3-BPG than adult Hb?

A

Lower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

[Hb] below what level in adult males is considered anaemia?

A

<130g/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

[Hb] below what level in adult females is considered anaemia?

A

<120g/L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

At what wavelength is spectrophotometry carried out to determine [Hb]? What does this measure?

A

540nm

Optical density

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What is Beer’s Law?

A

Optical density of a Hb solution is proportional to Hb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

How is a Hb solution stabilised?

A

Cyan-Methaemoglobin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

When may haematocrit not be a good marker of anaemia?

A

In rapid blood loss:
- [Hb] and Hct could be = as plasma volume also drops
Haemodilution:
- Same RBC mass but decreased [Hb] and Hct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Why do reticulocytes stain purple/deeper red than mature RBCs?

A

They still have remnants of RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What are the two pathophysiological classifications of anaemia?

A 
Decreased production:
- Hypoproliferation
- Maturation abnormality
Increased loss/Destruction:
- Bleeding
- Haemolysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

If MCV is low (microcytic), problems with what part of the production of red cells should be considered defective?

A

Haemoglobinisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

If MCV is high (macrocytic), problems with what part of the production of red cells should be considered defective?

A

Maturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What compound is protoporphyrin made from?

A

Porphobilinogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Where is protoporphyrin made?

A

Mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What is haem made from?

A

Fe2+

Protoporphyrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

Where is haem made?

A

Cytosol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What is Hb made from?

A

Haem

Globins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

Where is Hb made in the cell?

A

Cytosol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

Shortage of what components in the production of Hb result in microcytic anaemias?

A

Globins

Haem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What is deficient in hypochromic microcytic anaemia?

A

Hb synthesis (cytoplasmic defect)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What can cause a haem deficiency?

A

Lack of iron for erythropoiesis
Problems with porphyrin synthesis
Congenital sideroblastic anaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What can cause problems with porphyrin synthesis?

A

Lead poisoning

Pyridoxine responsive anaemias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

What is thalassaemia?

A

Globin deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

How much iron is absorbed per day?

A

1mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

How much iron exists in the plasma?

A

~4mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

How much iron is stored in parenchymal tissues (eg. liver, other)?

A

500mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

How is iron in parenchymal tissues stored?

A

Ferritin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

How much iron is lost from parenchymal tissues per day?

A

1mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

How much iron is present in the erythroid marrow?

A

150mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

How much iron is present in red cell Hb?

A

2500mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

How much iron is in macrophage stores?

A

500mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

How is iron stored in macrophages?

A

Ferritin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

What is circulating iron bound to?

A

Transferrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

How can transported iron be assessed?

A

Serum iron
Transferrin
Transferrin saturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

How many binding sites does transferrin have?

A

Two

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

What donor tissues does transferrin transport iron from?

A

Macrophages
Intestinal cells
Hepatocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

How is transferrin saturation affected in iron deficiency?

A

Reduced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

How is transferrin saturation affected in anaemia of chronic disease?

A

Reduced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

How is transferrin saturation affected in genetic hemochromatosis?

A

Increased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

How many ferric (Fe3+) ions can ferritin store?

A

4000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

Where is most ferritin present?

A

Intracellularly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

There is a tiny amount of ferritin present in the serum, what does this reflect?

A

Intracellular ferritin synthesis in response to iron status

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

What does low ferritin indicate?

A

Iron deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

What are relative causes of iron deficiency?

A

Women of child-bearing age

Children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

What is an absolute cause of iron deficiency?

A

Vegetarian diet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

What malabsorptive conditions can result in iron deficiency?

A

Coeliac disease

Achlorhydia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

What is the average volume of blood loss from menstruation a month? What is this equivalence in iron mass?

A

30-40ml/month

15-20mg/month

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

What are the consequences of negative iron balance?

A
  1. Exhaustion of iron stores
  2. Iron deficient erythropoiesis (Falling RBC MCV)
  3. Microcytic anaemia
  4. Epithelial changes (skin, koilonychia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

What is macrocytosis?

A

Enlargement of RBCs with normal [Hb]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

What is macrocytic anaemia?

A

Increased RBC volume with decreased [Hb] and number of RBCs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

What units is MCV measured in?

A

Femtolitres (1 femtolitre = 10^-15L)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

What is the normal range for MCV?

A

80-100fL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

What is a megaloblast?

A

An abnormally large nucleated red cell precursor with an immature nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

What are the prominent defects in megaloblastic anaemias?

A

DNA synthesis

Nuclear maturation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

What is relatively preserved in megaloblastic anaemias?

A

RNA synthesis

Hb synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

What happens to developing erythroid cells in the marrow?

A

Accumulate Hb
Decrease in size
Stop dividing and lose nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

What regulates the loss of the nucleus in developing erythrocytes?

A

Hb content

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

Why do megaloblastic anaemias cause increased MCV?

A

Cytoplasma is mature (and big) enough to divide
Nucleus is still immature:
- Cell thinks it has the right amount of Hb so doesn’t divide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
123
Q

What are the main deficiencies that result in megaloblastic anaemia?

A

Vitamin B12 deficiency

Folate deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
124
Q

What drugs can cause megaloblastic anaemia?

A

Folic acid antagonists (eg. Methotrexate)
Phenytoin
Nitrous oxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
125
Q

What are Vitamin B12 and Folate essential for?

A

Nuclear maturation:

- Enable chemical reactions that provide nucleosides for DNA synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
126
Q

What does the Methionine cycle produce?

A

s-adenosyl methionine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
127
Q

What is the folate cycle important for?

A

Nucleoside synthesis

eg. Uridine to Thymidine conversion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
128
Q

What is the function of s-adenosyl methionine?

A

Methyl donor to DNA, RNA, proteins, lipids and folate intermediates
?Impact on myelin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
129
Q

An inherited deficiency of what receptors in the ileum can result in a vitamin B12 deficiency?

A

Cubin receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
130
Q

What are dietary folates converted to?

A

Monoglutamate

131
Q

What is the dietary source of vitamin B12?

A

Animal meat

132
Q

What are dietary sources of folate?

A

Leafy veg.
Yeast
(Destroyed by cooking)

133
Q

How long is vitamin B12 stored in the body?

A

2-4 years

134
Q

How long is folate stored in the body?

A

4 months

135
Q

Where is vitamin B12 absorbed?

A

Ileum

136
Q

Where is folate absorbed?

A

Duodenum

Jejunum

137
Q

What is the daily requirement of vitamin B12?

A

1-3 micrograms/day

138
Q

What is the daily requirement of folate?

A

100 micrograms/day

139
Q

What stomach pathologies can result in a B12 deficiency?

A

PA
Atrophic gastritis
PPIs/H2 receptor antagonists
Gastrectomy/Bypass

140
Q

How can chronic pancreatitis result in megaloblastic anaemia?

A

Causes a B12 deficiency

141
Q

How can folate be utilised excessively resulting in its deficiency?

A

Haemolysis
Exfoliating dermatitis
Pregnancy
Malignancy

142
Q

What drugs can result in a folate deficiency?

A

Anticonvulsants

143
Q

What symptoms are common to both vitamin B12 and folate deficiency?

A 
Weight loss
Diarrhoea
Infertility
Sore tongue
Jaundice
Developmental problems
144
Q

What symptoms are caused by vitamin B12 deficiency only? What are they related to?

A

Myelin:

  • Dorsal column abnormalities
  • Neuropathy
  • Dementia
  • Psychiatric manifestations
145
Q

What is the pathology behind pernicious anaemia?

A

Autoimmunity resulting in the destruction of gastric parietal cells

146
Q

What is pernicious anaemia associated with?

A 
Atrophic gastritis
PMHx/FHx of other autoimmune disease:
- Hypothyroidism
- Vitiligo
- Addison's Disease
147
Q

How do dendritic cells play a role in pernicious anaemia?

A

Clear apoptotic parietal cells produced during turnover of gastric mucosa
Activation of CD4+ T-cells:
- Recognise H+/K+ ATPase expressed in parietal cells

148
Q

What features of an FBC would be seen in pernicious anaemia?

A

Macrocytic anaemia

Pancytopaenia (in some)

149
Q

What features of a blood film would be seen in pernicious anaemia?

A 
Macrovalocytes
Hypersegmented neutrophils (3-5 nuclear segments)
150
Q

What autoantibodies might be seen in pernicious anaemia?

A 
Anti-gastric parietal cell (GPC):
- Sensitive
- Not specific
Anti-intrinsic factor (IF):
- More specific
- Not sensitive
151
Q

What test, that is not routinely used, can be used to diagnose pernicious anaemia?

A

Schilling’s Test

152
Q

What can cause macrocytosis but are not usually causes of macrocytic anaemia?

A

Alcohol
Liver disease
Hypothyroidism

153
Q

What are other causes of macrocytic anaemia?

A

Myelodysplasia
Myeloma
Aplastic anaemia

154
Q

How can reticulocytosis result in spurious macrocytosis?

A

Marrow response increases in:
- Acute blood loss
- Haemolysis
Reticulocytes are bigger so increased MCV

155
Q

What is another cause of spurious macrocytosis?

A

Cold-agglutinins:

- Clumps of agglutinated cells registered as 1 ‘giant cell’

156
Q

How can pernicious anaemia cause mild jaundice?

A

Intramedullary haemolysis (ineffective erythropoiesis):

  • RBCs die prematurely in marrow
  • Hb and lactate dehydrogenase are released
  • Hb converted bilirubin
157
Q

How soon does plasma have to be frozen to be called fresh frozen plasma?

A

8 hours

158
Q

How much of a therapeutic dose of platelets is obtained from one blood donation?

A

1/4

159
Q

How much blood is taken is the typical blood donation?

A

465ml

160
Q

What is the minimum weight of an individual who can donate blood?

A

50kg

161
Q

How are RBCs stored?

A

At 4 degrees celsius

Shelf life of 35 days

162
Q

What happens in RBCs are removed for more than 30 minutes?

A

Transfuse within 4 hours
OR
Discard

163
Q

How are platelets stored?

A

Store at room temp. (22 degrees) with continual agitation (promotes gas exchange)
Shelf life of 7 days (if bacterial monitoring)

164
Q

How soon must platelets be transfused?

A

Within 1 hour

165
Q

How is fresh frozen plasma stored?

A

At -30 degrees
For up to 3 years
Thaw prior to transfusion

166
Q

How soon must FFP be transfused once thawed?

A

4 hours

167
Q

When is FFP used?

A

To replace coagulation factors:

  • Blood loss
  • Liver disease (can’t make own)
168
Q

What are the structures of naturally occurring ABO-Abs?

A

Mostly IgM

Some IgG

169
Q

On what chromosome is our ABO blood group inherited on?

A

Chromosome 9

170
Q

What do ‘A’ and ‘B’ code for?

A

Specific transferase enzymes:

- Add a sugar residue to a precursor ‘H’ substance on RBC membrane

171
Q

What is the recessive ABO gene?

A

‘O’ (it’s silent)

172
Q

On what chromosome is our Rhesus blood group inherited on?

A

Chromosome 1

173
Q

What is the blood group denoted by K and k?

A

Kell

174
Q

What is the blood group denoted by Fya and Fyb?

A

Duffy

175
Q

What is the blood group denoted by Jka and Jkb?

A

Kidd

176
Q

What are some possible indications for red cell transfusion?

A

Low Hb with:

  • Reduced exercise capacity
  • Congenital medical/surgical problems
  • Heart/Lung disease
  • “Anaemia” symptoms
177
Q

What is the typical volume of blood in a person?

A

70ml/kg

178
Q

How can blood volume be maintained before a blood transfusion is prescribed?

A

Saline

Albumin gelofusion

179
Q

How long does it take for a full ABO, Rh(D), Ab screen and cross-match?

A

1 hour

180
Q

How long does it take for a type specific (ABO and Rh(D) and immediate cross-match)?

A

10-20 minutes

181
Q

What blood can be used immediately in an emergency?

A

O negative blood

182
Q

What level of urine output should be maintained in acute blood loss?

A

> 30ml/hr

183
Q

What [Hb] should be maintained in acute blood loss?

A

> 100g/L

184
Q

How long does platelet apheresis take?

A

30-90 minutes

185
Q

How often can a person donate platelets by platelet apheresis?

A

Every 3 weeks

186
Q

What are the benefits of prescribing a dose of platelets obtained from apheresis compared to a dose pooled from 4 donors?

A

Reduced risk of infection

Reduced risk of tissue Ag sensitisation

187
Q

What should the platelet level in thrombocytopaenia be maintained at following:

  • General surgery
  • Neurosurgery?
A 
General = 50x10^9/L
Neurosurgery = 100x10^9/L
188
Q

What are the indications for FFP?

A

Correcting coag. deficiency in liver disease with bleeding
Coagulopathy following massive transfusion
DIC:
- Overwhelming infection
- ABO mismatch

189
Q

In an immediate haemolytic transfusion reaction, what effects do C3a and C5a have?

A

Anaphylotoxins:

  • Increase vascular permeability
  • Dilate blood vessels
  • Serotonin and Histamine release (fever, chills, hypotension, shock)
190
Q

In an immediate haemolytic transfusion reaction, what effects does the MAC have?

A

Haemolysis of transfused RBCs

191
Q

What activates the kinin system in an immediate haemolytic transfusion reaction?

A

Factor XIIa

192
Q

When the kinin system is activated, what happens?

A 
Formation of bradykinin:
- Arteriolar dilatation
- Increased vascular permeability
Hypotension:
- Catecholamine release
- Vasoconstriction in kidneys (and other organs)
193
Q

When does a delayed haemolytic transfusion reaction occur?

A

5-10 days post-transfusion

194
Q

What are the lab features of a delayed haemolytic transfusion reaction?

A 
Anaemia
Spherocytes
Increased bilirubin and LDH
Positive DAGT +/or red cell allo-Ab
\+/- renal failure
195
Q

What causes a febrile non-haemolytic transfusion reaction?

A

Abs against contaminating white cells:

- Cytokines and vasoactive substances released from white cells during storage

196
Q

How can a febrile non-haemolytic transfusion reaction be investigated?

A

HLA Abs

No evidence of RBC incompatibility

197
Q

How can a febrile non-haemolytic transfusion reaction be treated?

A

Antipyretics

Leucodepleted blood components

198
Q

How can urticarial blood transfusion reactions be treated?

A

Slow transfusion

Antihistamines

199
Q

What patients are at most risk of having circulatory overload during a blood transfusion?

A

Elderly

CCF

200
Q

How can circulatory overload be prevented?

A

Slow transfusion rate

Diuretics (not good practice)

201
Q

What bacterial infections are related to red cell transfusions?

A

Pseudomonas

Yersinia

202
Q

What bacterial infections are related to platelet transfusions?

A

Staph.
Strep.
Serratia
Salmonella

203
Q

What is the structure of HbA?

A

2 alpha chains

2 beta chains

204
Q

What is the structure of HbA2?

A

2 alpha chains

2 delta chains

205
Q

Where are the alpha-like genes for Hb?

A

Chromosome 16

206
Q

How many alpha-like genes are on each chromosome?

A

2 alpha genes per chromosome 16 (4 total)

207
Q

Where are the beta-like genes for Hb?

A

Chromosome 11

208
Q

How many beta-like genes are on each chromosome?

A

1 beta gene per chromosome 11 (2 total)

209
Q

When are adult levels of Hb reached?

A

6-12 months of age

210
Q

What are haemoglobinopathies?

A

Hereditary conditions affecting globin chain synthesis

211
Q

How are most haemoglobinopathies inherited?

A

Autosomal recessive

212
Q

What are thalassaemias?

A

Hereditary disorders of globin chain synthesis

213
Q

What type of anaemia do thalassaemias result in?

A

Microcytic hypochromic

214
Q

How does alpha thalassaemia result?

A

Deletion of one or both alpha genes from chromosome 16

215
Q

What is alpha thalassaemia trait?

A

One or two genes missing

216
Q

What is HbH disease?

A

Only one functional alpha-gene present on one chromosome 16

217
Q

What is Hb Barts Hydrops Foetalis?

A

No functional alpha genes on either chromosome 16

218
Q

How can alpha thalassaemia trait be distinguished from iron deficiency?

A

Ferritin normal

RBC count raised

219
Q

What does a FBC show in HbH disease?

A

Anaemia
Very low:
- MCV
- MCH

220
Q

What happens to Hb in HbH disease?

A

Excess beta chains form tetramers (beta4):

  • Called HbH
  • Cannot carry oxygen
221
Q

What are HbH bodies?

A

Red cell inclusions seen in HbH disease with a special stain

222
Q

What causes splenomegaly in HbH disease?

A

Extramedullary haematopoiesis

223
Q

What causes jaundice in HbH disease?

A

Haemolysis

Ineffective erythropoiesis

224
Q

How are severe cases of HbH disease treated?

A

Splenectomy

+/- Transfusion

225
Q

What are some long term sequelae of HbH disease?

A

Growth retardation
Gallstones
Iron overload

226
Q

Where is HbH disease most common?

A

SE Asia
Middle East
Mediterranean (where (–/alpha alpha) is prevalent)

227
Q

What forms of Hb are the majority at birth in Hb Bart’s Hydrops Foetalis Syndrome?

A

Hb Bart’s (gamma4)

HbH (beta4)

228
Q

What are the clinical features of Hb Bart’s Hydrops Foetalis Syndrome?

A

Severe anaemia (many nucleated RBCS in film)
Cardiac failure and oedema
Growth retardation
Severe hepatosplenomegaly
Skeletal and cardiovascular abnormalities
Most die in utero

229
Q

In beta thalassaemia, only beta chains are affected, what kind of Hb is affected?

A

HbA only

230
Q

Where are the highest levels of beta thalassaemia carriers?

A

SE Asia
Cyprus
Sardinia

231
Q

What causes beta thalassaemia trait?

A

Reduced beta/beta
OR
Absent beta/beta genes

232
Q

How can beta thalassaemia trait present?

A

Asymptomatic

No/Mild anaemia and low MCV/MCH

233
Q

What causes beta thalassaemia intermedia?

A

Reduced beta/reduced beta
OR
Absent beta/reduced beta

234
Q

How does beta thalassaemia intermedia present?

A

Moderate severity

Requires occasional transfucion

235
Q

What causes beta thalassaemia major?

A

Absent beta/absent beta

236
Q

How does beta thalassaemia major present?

A

Severe, lifelong transfusion dependency

237
Q

What does a film show in beta thalassaemia major?

A 
Microcytosis
Hypochromia
Anisopoikilocytosis:
- RBCs of varying sizes and abnormal shapes
Target cells
238
Q

When do patients with beta thalassaemia major tend to first present?

A

6-24 months

239
Q

What does extramedullary haematopoiesis in beta thalassaemia major cause?

A

Hepatosplenomegaly
Skeletal changes
Organ damage
Cord compression

240
Q

What is the purpose of the regular transfusion programme in managing beta thalassaemia major?

A

Maintain [Hb] at 95-105g/L
Suppress ineffective erythropoiesis
Inhibit over-absorption of iron

241
Q

What is the main cause of mortality in beta thalassaemia major?

A

Iron overload from transfusion (>70%)

242
Q

What endocrine dysfunctions occur in iron overload?

A

Impaired growth and pubertal development
Diabetes
Osteoporosis

243
Q

What cardiac diseases occur in iron overload?

A

Cardiomyopathy

Arrhythmias

244
Q

What liver disease occur in iron overload?

A

Cirrhosis

Hepatocellular cancer

245
Q

How does Desferrioxamine work?

A

Iron chelating

246
Q

How is Desferrioxamine administered?

A

S/C or IV

247
Q

What are the side effects of high dose Desferrioxamine?

A

Ocular toxicity

Ototoxicity

248
Q

What is the benefit of Deferiprone?

A

Better at removing cardiac iron

249
Q

What are the side effects of Deferiprone?

A

Arthralgia
GI upset
1% risk of agranulocytosis

250
Q

What does a blood film of thalassaemia show?

A

Hypochromia
Target cells
Anisopoikilocytosis

251
Q

What does high performance liquid chromatography show in beta thalassaemia trait?

A

Raised HbA2 (diagnostic)

252
Q

What does high performance liquid chromatography show in alpha thalassaemia trait?

A

It is normal

253
Q

What is the mutation in sickling disorders?

A

Point mutation in codon 6 of the beta globin gene that substitutes glutamine to valine

254
Q

What is the pathophysiology of sickling disorders?

A

BetaS produced
Alters Hb structure:
- HbS (alpha2, betaS2)

255
Q

What happens to Hb in sickling disorders?

A

Polymerised if exposed to low oxygen for prolonged period:

  • Distorts cell
  • Damages RBC membrane
256
Q

When may a sickle crisis occur in sickle trait?

A

Severe hypoxia:

  • High altitude
  • Under anaesthesia
257
Q

How is sickle cell disease inherited?

A

Autosomal recessive

258
Q

What is a sickle crisis?

A

Episodes of tissue infarction due to vascular occlusion

259
Q

What are the symptoms of sickle cell disease?

A

Dactylitis
Bone marrow, lung, spleen, CNS
Pain may be extremely severe

260
Q

What does chronic haemolysis in sickle cell disease result in?

A

Shortened RBC lifespan

261
Q

What happens to sickled RBCs?

A

Sequestered in liver and spleen

262
Q

How does hyposplenism result in sickle cell disease?

A

Repeated splenic infarcts

263
Q

What can precipitate a sickle crisis?

A 
Hypoxia
Dehydration
Infection
Cold exposure
Stress/Fatigue
264
Q

How is a painful sickle crisis treated?

A 
Opiates
Hydration
Rest
Oxygen
Antibiotics if infection
265
Q

What indicates a severe sickle crisis?

A

Chest

Neurological symptoms

266
Q

How is a severe sickle crisis treated?

A

Venesect -> Transfuse -> Venesect -> Transfuse:

  • Reduces [HbS]
  • Increases tissue perfusion
267
Q

What are the long term organ damages in sickle cell anaemia?

A 
Pulmonary hypertension
Renal disease
Avascular necrosis
Leg ulcers
Stroke
268
Q

How is hyposplenism treated in sickle cell disease?

A 
Prophylactic penicillin
Vaccination:
- Pneumococcus
- Meningococcus
- Haemophilus
269
Q

What bacteria often cause infections in sickle cell disease?

A

Encapsulated bacteria

270
Q

What are the other treatments for sickle cell disease?

A

Folic acid supplementation

Hydroxycarbamide can reduce severity by inducing HbF production

271
Q

What does HbSC disease increase the risk of?

A

Thrombosis

272
Q

What stain can identify reticulocytes by staining the rRNA?

A

New methylene blue

273
Q

What is extravascular haemolysis?

A

Taken up by reticuloendothelial system (liver, spleen)

274
Q

What is intravascular haemolysis?

A

RBCs destroyed within circulation

275
Q

What is released in extravascular haemolysis?

A

Release of protoporphyrin:

  • Unconjugated bilirubin causes jaundice and gallstones
  • Urobilinogenuria
276
Q

What results in intravascular haemolysis?

A

Haemogloboinaemia
Methaemoglobinaemia
Haemoglobinuria (Pink urine - black on standing)
Haemosiderinuria

277
Q

What can cause intravascular haemolysis?

A 
ABO incompatibility
G6PD deficiency
Severe falciparum malaria (Blackwater fever)
Even rarer:
- Paroxysmal Nocturnal Haemoglobinuria
- Paroxysmal Cold Haemoglobinuria
278
Q

On a blood film, how do membrane damaged red cells appear?

A

Spherocytes

279
Q

On a blood film, what do red cell fragments (schistocytes) indicate?

A

Mechanical damage

280
Q

What do Heinz bodies on a blood film indicate? What might they be seen in?

A

Oxidative damage

G6PD deficiency

281
Q

What immunoglobulins are involved in warm autoimmune haemolysis?

A

IgG

282
Q

What immunoglobulins are involved in cold autoimmune haemolysis?

A

IgM

283
Q

What are the causes of warm autoimmune haemolysis?

A 
Idiopathic (commonest)
Autoimmune disorders (SLE)
Lymphoproliferative disorders (CLL)
Drugs (penicillins, NSAIDs, quinidine)
URTIs
284
Q

What are the causes of cold autoimmune haemolysis?

A

Idiopathic
Infections (EBV, mycoplasma)
Lymphoproliferative disorders

285
Q

How is autoimmune haemolysis investigated?

A

Direct Coombs’ Test

286
Q

What sort of immunoglobulins are involved in an alloimmune immediate haemolytic reaction? Is it intra- or extravascular?

A

IgM

Intravascular

287
Q

What sort of immunoglobulins are involved in an alloimmune delayed haemolytic reaction? Is it intra- or extravascular?

A

IgG

Extravascular

288
Q

What is Zieve’s Syndrome?

A 
Haemolysis due to an acquired membrane defect
Alcoholic liver disease
Hyperlipidaemia
Blood film:
- Anaemia
- Polychromatic macrocytes
- Irregularly contracted cells
289
Q

How can Paroxysmal Nocturnal Haemoglobinuria be tested for?

A

Ham’s Acid Haemolysis Test (Tests for RBC fragility)

290
Q

What can a Vitamin E deficiency cause?

A

An acquired RBC membran defect

291
Q

What are Pappenheimer bodies seen in?

A

Beta thalassaemia major

292
Q

What can serum ferritin act as? Because of this, when else can it be raised?

A

Acute phase protein:

  • Infection
  • Malignancy
293
Q

What iron transporters aid in the absorption of iron?

A

DMT-1

Ferroportin

294
Q

What is Hepcidin?

A

Major negative regulator of iron uptake:

- Downregulates ferroportin

295
Q

What organ produces Hepcidin and in response to what?

A

In the liver in response to:

  • Iron load
  • Inflammation
296
Q

What is the function of DMT-1?

A

Transports iron into the duodenal enterocyte

297
Q

What is the function of ferroportin?

A

Facilitates iron export from enterocyte

Passed on to transferrin

298
Q

What is primary iron overload (primary haemochromatosis)?

A

Long-term excess iron absorption with parenchymal (rather than macrophage) iron loading

299
Q

What are the clinical features of hereditary haemochromatosis?

A 
Weakness/Fatigue
Joint paints
Impotence
Arthritis
Cirrhosis
Diabetes
Cardiomyopathy
300
Q

When does hereditary haemochromatosis present?

A

Middle/Old age when iron overload >5g

301
Q

What are the potential mutations that can result in primary haemochromatosis?

A

Mutations of HFE gene:

  • C282Y
  • H63D
  • Mainly results in reduced hepcidin synthesis
302
Q

What transferrin saturation might suggest a risk of iron loading?

A

> 50%

303
Q

What serum ferritin levels can indicate iron overloading??

A

> 300 micrograms/L in men

>200 micrograms/L in pre-menopausal women

304
Q

How is hereditary haemochromatosis treated?

A

Weekly phlebotomy:

  • 450-500ml
  • Equivalent to 200-250mg iron
305
Q

What is the initial aim of hereditary haemochromatosis?

A

Exhaust iron stores:

- Ferritin <20 mcg/L

306
Q

After initial therapy for hereditary haemochromatosis, what is the purpose of further treatment?

A

Keep ferritin <50 mcg/L

307
Q

What is the main cause of death in hereditary haemochromatosis?

A

Hepatoma

308
Q

How is secondary iron overload treated?

A

Iron chelating agents

309
Q

Below what [Hb] level is anaemia likely in children (6 months to 6 years)?

A

110g/L

310
Q

Below what [Hb] level is anaemia likely in children (6-14 years)?

A

120g/L

311
Q

Below what [Hb] level is anaemia likely in adult males?

A

130g/L

312
Q

Below what [Hb] level is anaemia likely in adult females (non-pregnant)?

A

120g/L

313
Q

Below what [Hb] level is anaemia likely in adult females (pregnant)?

A

110g/L

314
Q

What can indicate impaired RBC production?

A

Anaemia with lesser reticulocyte response

315
Q

What mnemonic can be used to remember the causes of hypochromic microcytic anaemia?

A 
T - Thalassaemia
A - Anaemia of chronic disease
I - Iron deficiency
L - Lead poisoning
S - Sideroblastic anaemia
316
Q

What hypoproliferative disorders can result in a normochromic normocytic anaemia?

A 
Chronic disease:
- Inflammation
- Infection
- Malignancy
Anaemia of renal failure
Hypometabolic states (eg. Hypothyroidism(
Marrow failure:
- Aplasia
- Infiltration
317
Q

Where does haematopoiesis occur in the embryo?

A

Yolk sac then liver

Spleen from 3rd - 7th month

318
Q

Where does haematopoiesis occur in adults?

A

Bone marrow of:

  • Skull
  • Ribs and sternum
  • Pelvis
  • Proximal ends of femur
319
Q

When does neutrophilia occur physiologically?

A

Infection
Trauma
Infarction

320
Q

What is the function of eosinophils?

A

Fight parasitic infections

Hypersensitivity

321
Q

When can eosinophilia occur?

A

Asthma

Atopic rhinitis

322
Q

What is the structure of a mature lymphocyte?

A

Small

Condensed nucleus and rim of cytoplasm

323
Q

What is the structure of an activated (/atypical) lymphocyte?

A

Large
Plentiful blue cytoplasm extending round neighbouring RBCs
Nucleus more ‘open’

Year 3 - Haematology (DP) (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions