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Phase 2a Haematology > Haematology > Flashcards

Haematology Flashcards

1
Q

Why might pregnant women get anaemia?

A

Raised plasma volume

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2
Q

What does MCV stand for?

A

Mean cell volume

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3
Q

Why might someone with anaemia be asymptomatic?

A

Due to a rise in BPG causing the oxygen dissociation curve to shift to the R

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4
Q

What are some symptoms of anaemia?

A

‘Tired all the time’ (fatigue + lethargy/malaise), headaches, faintness, SOB, Angina

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5
Q

What are some signs of anaemia>

A

Pallor (+ conjunctival pallor), tachycardia, compensatory heart failure

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6
Q

What does MCH stand for? What is it an indication of?

A

Mean corpuscular haemoglobin - amount of Hb per RBC

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7
Q

What is MCHC?

A

Mean cell Hb concentration - amount of Hb relative to the size of the cell

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8
Q

How do you look at RBCs and determine their MCV, MCH, MCHC?

A

Blood film

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9
Q

Give an example of a disease where the cell types/sizes on a blood film are dimorphic

A

Coeliac disease

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10
Q

What cell size will you see in coeliac disease?

A

2 cell types/sizes: macrocytic (due to B12/folate malabsorption) and microcytic (iron malabsorption)

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11
Q

How do you evaluate bone marrow?

A

Aspirate from the iliac crest OR use trephine

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12
Q

Where is iron stored?

A

Bone marrow

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13
Q

Give 3 causes of microcytic anaemia

A

Fe deficiency, chronic disease and thalassaemia

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14
Q

Give 3 causes of normocytic anaemia

A

Acute blood loss, anaemia of chronic disease, combined haematinic deficiency

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15
Q

Give 4 causes of macrocytic anaemia

A

Acute blood loss, liver failure + alcohol excess, hypothyroidism

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16
Q

What type of anaemia (MCV) does haematological causes (BM failure, BM infiltration, haemolytic anaemia, anti-metabolite therapy) causes?

A

Macrocytic anaemia

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17
Q

What haemolytic anaemia doesn’t cause macrocytic anaemia? What type of anaemia is it?

A

Thalassaemia - microcytic anaemia

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18
Q

What type anaemia is haemolytic anaemia?

A

Macrocytic (Except thalassaemia)

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19
Q

What plasma protein transports iron in the blood? Where does it transport iron to?

A

Plasma transferrin - to the bone marrow for storage

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20
Q

What is the most common cause of anaemia world-wide?

A

Iron deficiency

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21
Q

What proportion of menstruating women have iron deficiency anaemia?

A

14%

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22
Q

What are the causes of iron deficiency anaemia?

A

Blood loss (Chronic), menstruation, Hook worm (blood loss), malabsorption, poor dietary intake

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23
Q

What disease might cause malabsorption of iron?

A

Coeliac disease

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24
Q

What iatrogenic cause may cause malabsorption of iron?

A

Gastrectomy

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25
Q

What symptoms might you get with iron deficiency anaemia?

A

Fatigue, headaches, faint, SOB, palpitations, dyspnoea (Severe SOB)

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26
Q

Why might someone get angina as a symptom of anaemia?

A

Because they have pre-existing coronary artery disease (IHD) which has gone unnoticed until now as there is supply demand mismatch (less O2 carrying capacity) to meet the demands of the heart muscle

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27
Q

What are some signs of iron deficiency anaemia?

A

Koilonycia (spoon shaped nails), brittle hair + nails, smooth tongue (atrophy of tongue papillae), angular somatitis, glositis (red tongue)

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28
Q

What should you ask in a Hx of anaemia to determine the cause?

A

Dietary intake, self medication (GI bleeding), blood in faeces, woman (duration + heaviness of periods), other diseases/symptoms (E.g. coeliac symptoms)?

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29
Q

What 4 tests might you do to determine whether the person has iron deficiency anaemia?

A

Blood count + blood film, serum iron, serum ferritin, total iron binding capacity

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30
Q

What would you see on a blood film of iron deficiency anaemia?

A

MCV low (microcytic), MCH low (hypochromic)

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31
Q

What results would you get for serum iron and serum ferritin in iron deficiency anaemia?

A

Both will be low (ferritin may be high)

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32
Q

Why is serum ferritin not a reliable diagnostic tool for iron deficiency anaemia (why do you need to do serum iron + TIBC)?

A

because it is an acute phase protein and therefore rises in inflammation, infection…etc

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33
Q

What does serum ferritin reflect?

A

Iron stores

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34
Q

What tests might you do to determine the cause of the iron deficiency?

A

Pt Hx, serology (for coeliac), GI tract bleeding exam??

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35
Q

What treatments should you give a patient with iron deficiency anaemia?

A

Oral iron (ferrous sulfate) and treat the cause

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36
Q

What are the side effects of oral iron tablets?

A

GI upset (nausea, constipation, abdo pain…etc)

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37
Q

What compound is used in oral iron?

A

Ferrous sulfate

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38
Q

What result would total iron binding capacity give for iron deficiency anaemia?

A

High (don’t get confused)

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39
Q

If someone is in renal failure, what causes their anaemia? What treatment should they be given?

A

Reduced production of EPO - give recombinant EPO therapy

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40
Q

What MCV is seen in normocytic anaemia?

A

Normal (but low Hb conc.)

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41
Q

What is needed for vitamin B12 absorption? What produces it?

A

Intrinsic factor from parietal cells

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42
Q

What is the role of vitamin B12?

A

Normal NS functioning + formation of RBCs

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43
Q

What are the 2 main causes of vitamin B12 malabsorption?

A

Pernicious anaemia and malabsorption

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44
Q

What causes malabsorption of vitamin B12?

A

(Pernicious anaemia), diet deficiency, gastrectomy, iliectomy, coeliac, metformin

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45
Q

What groups of people are at risk of vitamin B12 diet deficiency?

A

Vegans

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46
Q

What is pernicious aneamia?

A

An autoimmune disease that causes vitamin B12 deficiency

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47
Q

What auto-antibodies are found in pernicious anaemia? Which is more common?

A

Antibodies against parietal cells (90%) and intrinsic factor antibodies (50%)

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48
Q

What other autoimmune diseases are associated with pernicious anaemia?

A

Addison’s disease, thyroid disease (Hashimoto’s), …

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49
Q

What is the main cause of vitamin B12 deficiency?

A

Pernicious anaemia

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50
Q

What is the pathology of pernicious anaemia?

A

Auto-antibodies –> atrophic gatritis w/ loss of parietal cells in gastric mucosa –> Intrinsic factor not produced –> vitamin B12 malabsorption

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51
Q

What is the classic symptom of pernicious anaemia? (EXAM)

A

Progressively increasing anaemia symptoms

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52
Q

What are the signs of pernicious anaemia and vitamin B12 deficiency?

A

Glositis, angular stomatitis, neurological features (polyneuropathy [periphera neuropathy], prgressive weakness, ataxia, paraplegia if untreated, dementia)

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53
Q

What cancer risk are those with pernicious anaemia at increased risk of getting

A

Gastric carcinoma

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54
Q

Why might a person have mild jaundice in pernicious anaemia?

A

It is a cause of megaloblastic anaemia (large cells) –> ^ Hb breakdown into bilirubin

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55
Q

What tests might you do if you suspect pernicious anaemia (or vitamin B12 def. anaemia)?

A

Blood film, blood count, serum vitamin B12, LDH, serum bilirubin, serology

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56
Q

What would you see on serology for non-autoimmune causes of anaemia?

A

Normal

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57
Q

Why do you carry out a serum bilirubin in vitamin B12 def. anaemia?

A

Because the patient may present with jaundice

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58
Q

Why might serum bilirubin be raised in vitamin B12 deficiency anaemia?

A

Megaloblastic anaemia (large cells) –> ^ Hb breakdown into bilirubin

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59
Q

What does a blood film show in pernicious + vit. B12 deficiency anaemia?

A

Megaloblastic anaemia

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60
Q

What is test shows that the person is vit B12 deficient?

A

Serum vitamin B12

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61
Q

What does LDH stand for? What value does in have in pernicious anaemia?

A

Lactic dehydrogenase + raised

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62
Q

When would you carry out a BM examination if someone has anaemia?

A

When the cause isn’t straightforward

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63
Q

What would you see on serology for pernicious anaemia?

A

Auto-antibodies to parietal cells and intrinsic factor

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64
Q

What test might you do to distinguish between pernicious anaemia and other causes of vitamin B12 deficiency?

A

Duodenal biopsy for coeliac

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65
Q

What treatment should you give someone if the cuase of their anaemia is untreatable malabsorption (such as pernicious anaemia)?

A

IM hydroxocobalamin

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66
Q

What treatment should you give to treat dietary vitamin B12 insufficiency?

A

Oral vitamin B12

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67
Q

What foods is folate found?

A

Green vegetables, liver, kidney

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68
Q

What might occur if a pregnant woman is folate deficient?

A

Spina bifida

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69
Q

Where is folate absorbed?

A

duodenum and jejunum

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70
Q

What is folate used for?

A

DNA synthesis (RBC development)

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71
Q

What is the main cause of folate deficiency?

A

Poor dietary intake

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72
Q

What are some causes of folate deficiency?

A

Poor dietary intake, alcohol, drugs, excessive utilisation (to make more RBC) e.g. pregnancy or chronic haemolytic anaemia

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73
Q

Give an example of a drug that causes folate deficiency?

A

Methotrexate

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74
Q

What is the differences in presentation between vitamin B12 def. anaemia and folate def. anaemia?

A

In folate def. anaemia there isn’t neuropathy

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75
Q

What two investigations can you do to measure the pt’s folate levels?

A

Serum folate and red cell folate

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76
Q

Which Ix gives a better indication of tissue folate levels: serum or red cell folate?

A

Red cell folate

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77
Q

What does BM analysis show in B12 and folate def. anaemia?

A

Megaloblastic haematopoiesis (activity)

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78
Q

What is the treatment for folate deficiency?

A

Treat the cause + oral folic acid

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79
Q

What must you give pregnant women during their pregnancy?

A

Prophylactic folic acid to ensure neural tube closure

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80
Q

What is a cause of macrocytic normochromic anaemia?

A

Alcohol excess (biggest cause), liver disease, pregnancy..

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81
Q

What type of anaemia does BM failure show?

A

Macrocytic anaemia

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82
Q

What are the two primary causes of anaemia due to BM failure?

A

Idiopathic (most common) and inherited (Fanconi’s anaemia)

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83
Q

What drugs can cause BM failure?

A

Cytotoxic drugs

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84
Q

What infections can cause BM failure?

A

Hepatitis, TB, HIV

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85
Q

What is pancytopaenia

A

Reduction in all cell lines: RBCs, WBCs and platelets)

86
Q

What causes pancytopaenia?

A

BM failure (leukaemia, primary: aplastic anaemia), hypersplenism (^ peripheral destruction)

87
Q

What occurs in BM failure?

A

Reduction in pluripotent stem cells (can be only one cell line)

88
Q

What are the clinical features of BM failure?

A

^ Infections (reduced WBCs), anaemia (reduction in RBCs), bleeding + brusing (platelet reduction)

89
Q

What signs might occur in BM failure?

A

Hepatosplenomegaly + lymphadenopathy

90
Q

What will you see in a blood count of someone with BM failure?

A

Pancytopaenia (Reduction in all cell lines)

91
Q

What is needed for diagnosis of BM failure?

A

BM examination/biopsy (aspirate from iliac crest)

92
Q

What must your Ix’s also do to determine whether the cause of pancytopaenia is BM failure? How will you

A

Distinguish from other causes of pancytopaenia. Do a BM examination

93
Q

What does BM examination show for someone with BM failure?

A

hypocellular marrow w/ ^ fat spaces

94
Q

What is the treatment for BM failure?

A

Remove the causative agent (E.g. drugs, radiation…)

95
Q

How do you treat the anaemia and bleeding of BM failure?

A

Red cell transfusion therapy + platelet transfusion

96
Q

How do you treat the neutropaenia in BM failure?

A

Naeutropenic regimen (Abx?)

97
Q

How do you treat BM failure if Red cell + platelet transfusion doesn’t work?

A

Bone marrow Tx w/ immunosuppression (ciclosporin)

98
Q

What Haemolytic anaemia is not macrocytic?

A

Thalassaemia

99
Q

What are the two broad causes of Haemolytic anaemia?

A

Acquired and hereditary (genetic)

100
Q

What are the 3 types of hereditary causes of haemolytic anaemia?

A

RBC membrane defects, Haemoglobin abnormalities, Metabolic (enzyme) defects

101
Q

Give an example of a RBC membrane defect that cause haemolytic anaemia

A

Hereditary spherocytosis

102
Q

Give 2 examples of Hb abnormalities that cause haemolytic anaemia

A

Sickle cell disease and Thalassaemia

103
Q

Give two examples of metabolic (Enzyme) defects that cause Haemolytic anaemia

A

GP6D deficiency and pyruvate kinase deficiency

104
Q

What are the two acquired causes of haemolytic anaemia

A

Immune and non-immune

105
Q

Give 3 examples of non-immune acquired causes of haemolytic anaemia

A

Paroxysmal nocturnal haemoglobulinuria, infections (malaria), hypersplenism

106
Q

In paroxysmal nocturnal haemoglobulinuria, what happens to RBCs and why?

A

Lysed by activating complement (CDC) due to abnormal RBC surface markers

107
Q

What do you treat paroxysmal nocturnal haemoglobulinuria with?

A

Anti-coagulation + eculizumab

108
Q

Why do you treat paroxysmal nocturnal haemoglobulinuria with anti-coagulation?

A

Predisposition to clotting

109
Q

Why is malaria sometimes called black water fever?

A

Causes haemoglobulinuria (looks black)

110
Q

How does the bone marrow compensate for haemolytic anaemia (increased destruction of RBCs)? So what would you see on a blood count?

A

Increased reticulocytes

111
Q

What molecule might you see an increase of in haemolytic anaemia?

A

Bilirubin

112
Q

What molecule might you see an increase of in haemolytic anaemia in the urine?

A

Urobilinogen

113
Q

What genetic pattern does hereditary spherocytosis show?

A

Autosomal dominant

114
Q

What is the pathophysiology in hereditary spherocytosis?

A

deficiency of RBC membrane proteins –> ^ Na+ permeability –> rigid + large –> gets trapped in capillaries of spleen –> broken down by spleen (reticuloendothelial system)

115
Q

What is the most common membranopathy?

A

hereditary spherocytosis

116
Q

What group of people does hereditary spherocytosis occur in?

A

N. Europeans

117
Q

What is the commonest membrane protein that is deficient in hereditary spherocytosis?

A

Spectrin

118
Q

What does parvovirus cause in children? How does it affect hereditary spherocytosis?

A

slapped cheek syndrome. In hereditary spherocytosis it causes BM failure

119
Q

in general what is needed in BM failure?

A

Blood transfusion (RBCs, platelets…)

120
Q

What is seen on a blood film of a patient with hereditary spherocytosis?

A

^ reticulocytes + ^ spherocytes

121
Q

What is the management for hereditary spherocytosis?

A

Splenectomy

122
Q

What are the two conditions characterised Hb abnormality and haemolytic anaemia?

A

Thalassaemia and sickle cell disease

123
Q

What chains are seen in Foetal Hb?

A

2alpha and 2gamma globin chains

124
Q

What is the group of people affected by thalassaemia?

A

Spanish (irish)

125
Q

What is the pathophysiology behind thalassaemia

A

Reduced production of either alpha or beta globin chains

126
Q

What are the two types of thalassaemia?

A

Alpha thalassaemia and beta thalassaemia

127
Q

What type of anaemia is seen in thalassaemia?

A

Microcytic anaemia

128
Q

What type of mutation is mainly scene in alpha thalassaemia?

A

Deletions (genes)

129
Q

What type of mutation is mainly scene in beta thalassaemia?

A

point mutations

130
Q

What is the pathophysiology behind beta thalassaemia?

A

Point mutations –> highly unstable beta chains that can’t be used + excess alpha chains –> haemolysis

131
Q

What are the 3 clinical classifications of beta thalassaemia?

A

Thalassaemia minor, thalassaemia intermedia, thalassaemia major

132
Q

What is beta thalassaemia minor? How do they present? And what is the clinical presentation?

A

Heterozygous carrier for beta thalassaemia - asymptomatic

133
Q

How do you distinguish Thalassaemia from iron deficiency anaemia?

A

Do a serum ferritin, TIBC, serum iron

134
Q

What is thalassaemia intermdia and how does it present symptoms wise?

A

Combo of beta and alpha thalassaemia - symptoms: mild anaemia, ^ infections…etc

135
Q

What are the signs of thalassaemia intermedia?

A

recurrent ulcers, gallstones, splenomegaly and bone deformities

136
Q

What is the beta thalassaemia major? How does it present?

A

Heterozygous beta thalassaemia - severe anaemia symptoms

137
Q

Why does Beta thalassaemia major present at 6-12 months following gestation?

A

Because at 6-12 months is when all the HbF is replaced by HbA (HbF starts to replace HbA at 13 weeks following gestation) - HbF is unaffected by beta thalassaemia as it doesn’t contain beta globin chains

138
Q

Why is Foetal haemoglobin unaffected by beta thalassaemia but is by alpha thalassaemia? What does this mean in terms of presentation of each thalassaemia?

A

It has alpha chains but no beta chains. Therefore alpha thalassaemia presents at birth whilst beta thalassaemia presents later on (when HbF is replaced by HbA)

139
Q

What are the symptoms of beta thalassaemia major?

A

Failure to thrive, failure to feed, crying, severe anaemia symptoms, pale, classical facial features

140
Q

What can be seen on a skull XR of beta thalassaemia major?

A

Classic ‘hair on end appearance’

141
Q

What blood Ix’s would you carry out on someone with thalassaemia?

A

Blood film (MCH, MCV), serum ferritin/iron

142
Q

Why do you carry out a serum ferritin for thalassaemia?

A

Both cause microcytic anaemia (shown by the blood film) therefore it is to rule out Fe deficiency as a cause of microcytic anaemia

143
Q

What results to you see in beta thalassaemia?

A

blood film MCV + MCH (low), normal ferritin/iron

144
Q

What is the treatment for beta thalassaemia?

A

Regular blood transfusion, splenectomy

145
Q

What is the prblem with regular blood transfusion?

A

Iron overload: can leads to hepatic fibrosis + cirrhosis, DM, cardiac arrhythmias, hypothyroidism, HF and death

146
Q

How do you prevent iron overload from regular blood transfusion?

A

Iron chelation using either Desferrioxamine ascorbic acid (vitamin C) or Deferiprone

147
Q

How does thalassaemia present and why do the presentations vary?

A

Mild to severe - depends on how many genes are deleted (mutated) for the alpha chains

148
Q

How many alpha globin chain genes are found on a haploid chromosome 16?

A

4

149
Q

How many alpha globin chain genes in alpha thalassaemia need to be deleted for a clinical presentation?

A

2 (because if only one is deleted then there are still 3 other genes to produce a sufficient quantity of Hb alpha chains to prevent anaemia)

150
Q

What is the name of the condition when 4 alpha globin chain genes are deleted? What is it characterised by?

A

Hydrops fetalis - incompatible with life (stillborn)

151
Q

In the UK, what is the 1st and 2nd commonest genetic conditions?

A

1st: CF and 2nd: sickle cell disease

152
Q

Which group of people are affected by sickle cell disease?

A

Black people + Africans

153
Q

What globin chain does Sickle cell disease affect and when does it therefore present/manifest?

A

Beta globin chains and manifests at 6months (HbF –> HbS)

154
Q

Which malaria causing organism do sickle cell carriers have protection from?

A

Plasmodium falciparum

155
Q

What occurs to a HbS molecule when it desaturates from oxygen?

A

It sickles and become insoluble (polymerises and crystalises) –> causing RBC deformity/rigidity

156
Q

What is the commonest form of sickle cell?

A

HbSS

157
Q

What is the homozygous (carrier) and heterozygous state called for sickle cell disease?

A

HbAS and HbSS

158
Q

How does sickling/dehydration occur in sickle cell disease?

A

k+ leaves the cell by Gados channels

159
Q

Is sickling reversible?

A

Yes but after so many repeats of sickling it is irreversible

160
Q

What does sickling cause in sickle cell disease?

A

Haemolysis (reduced RBC life) and impaired passage of cells through smaller vessels leading to tissue infarction

161
Q

Despite being anaemia, why might a sickle cell disease pt feel well?

A

HbS releases oxygen more readily than HbA AND there is constant Hb range (until acute fall in sickle cell crisis)

162
Q

What precipitates RBC sickling?

A

Hypoxia, infection, dehydration, cold, acidosis

163
Q

What does sickling mean in terms of flexibility?

A

Less flexibility + rigid (can’t change shape like normal RBCs)

164
Q

When does sickle cell disease manifest in terms of clinical presentation?

A

6 months

165
Q

Is there variation in clinical presentation for someone with sickle cell disease?

A

Yes: some pts have few symptoms while others have recurrent sickle cell crisis (+ reduced life expectancy)

166
Q

What causes anaemia in patients with sickle cell disease? What type of anaemia is it?

A

Chronic haemolysis - macrocytic anaemia

167
Q

What can cause a huge fall in Hb in patients with sickle cell disease?

A

Splenic sequestration, BM aplasia, further haemolysis (due to other causes)

168
Q

What is sickle cell crisis characterised by?

A

Vaso-occlusion causing ishcaemia + pain

169
Q

What occurs in sickle cell crisis?

A

PAIN in hands + feet (dactylitis), severe pain in bones, fever, SOB (sickle chest syndrome - infarcts)

170
Q

What are some chronic complications of sickle cell disease?

A

Avascular necrosis (femur head), pulmonary hypertension, joint damage (avascular necrosis), pigment gall stones, hepatomegaly, background retinopathy

171
Q

What are the chronic and acute (crisis) respiratory complications of sickle cell disease?

A

Chronic: pulmonary hypertension

Acute (sickle cell crisis): acute chest syndrome (infarcts)

172
Q

What causes sickle cell crisis (acute complications)?

A

Vaso-occlusion

173
Q

What other complications can sickle cell crisis (vaso-occlusion) lead to?

A

Leg ulcers, spontaneous abortion/foetal death, stroke, MI, seizures…etc

174
Q

What tests would you carry out to diagnose sickle cell disease?

A

Blood count, blood films, sickle solubility test, Hb electrophoresis

175
Q

What must you do before surgery if a patient is from an ethnic group?

A

Firstly a sickle solubility test and then sickle cell disease screening

176
Q

What do blood counts and blood films show in sickle cell disease?

A

Blood counts show high reticulocyte count

Blood film shows high reticulocytes and sickling of RBCs

177
Q

What does sickle solubility test show in sickle cell disease? What must you do if the test is positive?

A

HbS precipitates in the reducing solution (because it desaturates)

178
Q

What test confirms the diagnosis of sickle cell disease? What does it show?

A

Hb electrophoresis (shows no HbA only HbS)

179
Q

What is the conservative management of sickle cell disease?

A

Avoid precipitating factors (hypoxia, infection, cold..), pneumococcal + influenza vaccination, folic acid, councelling (psychosocial issues, pregnancy and drugs)

180
Q

What is the drug treatment for chronic sickle cell disease (not acute crisis)?

A

Penicillin (daily), manage painful crisis with NSAIDs + paracetamol, hydroxycarbamide

181
Q

When should BM Tx be offered in sickle cell disease?

A

If they have severe, + recurrent crisis

182
Q

When should blood transfusions be offered in sickle cell disease?

A

TIA, stroke, acute chest syndrome, pregnancy, splenic sequestration crisis, before surgery

183
Q

If a painful crisis can’t be managed by NSAIDs + paracetamol, what should be the next stage in treatment?

A

Hospital admission

184
Q

If a sickle cell disease pt is admitted to hospital for a severe painful crisis, what analgesia should be given?

A

morphine or diamorphine + adjuvant non-opioid

185
Q

What does PCA stand for?

A

Patient controlled analgesia

186
Q

If a sickle cell disease pt is admitted to hospital for a severe painful crisis, what else should be given apart from analgesia?

A

Oxygen, laxatives (lactulose), anti-emetic, anti-pruritics (hydroxyzine), rehydration (IV saline or oral fluids)

187
Q

How does Hydroxycarbamide work in sickle cell disease?

A

Increases the amount of HbF

188
Q

What causes acute chest syndrome in sickle cell disease?

A

Infarcts to the lung

189
Q

Give two metabolic (enzyme) RBC disorders that causes haemolytic anaemia?

A

G6PD deficiency and pyruvate kinase deficiency

190
Q

What does G6PD stand for?

A

Glucose-6-phosphate dehydrogenase

191
Q

Is G6PD deficiency common?

A

Yes

192
Q

What type of genetic disease is G6PD deficiency?

A

X linked

193
Q

What is the role of G6PD?

A

It is involved in the hexose monophosphate shunt forming NADPH

194
Q

What is the role of NADPH in a red blood cell if red blood cells have no mitochondria? What does this mean in terms of the role of G6PD in a RBC?

A

Protection of the RBC from oxidative damage - therefore, G6PD provides protection of the RBC from damage and haemolysis by oxidants

195
Q

Why does G6PD deficiency cause haemolysis?

A

Less NADPH is produced so there is oxidative damage

196
Q

What are the clinical presentations of G6PD deficiency?

A

mostly asymptomatic, anaemia, jaundice, hemoglobinuria, ^ infections

197
Q

What is the triad of symptoms in G6PD deficiency CRISIS?

A

Jaundice, anaemia, haemoglobinuria

198
Q

What causes the triad of symptoms in G6PD deficiency CRISIS?

A

Rapid intravascular haemolysis

199
Q

What causes rapid intravascular haemolysis and G6PD deficiency crisis?

A

Favism (broad beans [VICIA FAVA]), henna, infection, drugs (quinolones, quinine, sulphonamides, nitrofurantoin)

200
Q

What is the common presentation of G6PD deficiency?

A

ASYMPTOMATIC (unless crisis precipitated by broad beans, drugs, henna causing RAPID haemolysis)

201
Q

What is G6PD deficiency crisis characterised by?

A

Anaemia, jaundice, haemoglobinuria

202
Q

What does a blood film show in G6PD deficiency between acute attacks (crisis)?

A

Normal cells

203
Q

What does a blood film show in G6PD deficiency during an acute attack (crisis)?

A

Bite and blister cells, reticulocytes ^, Heinz bodies

204
Q

What is the diagnostic Ix for GP6D deficiency?

A

Enzyme assay showing G6PD deficiency

205
Q

What is the treatment for G6PD deficiency?

A

Avoid precipitants (henna, drugs, broad beans), treat infection, blood transfusion in acute crisis

206
Q

What is the function of pyruvate kinase?

A

Involved in the last step of glycolysis

207
Q

What occurs in pyruvate kinase deficiency?

A

Reduced ATP production –> reduced RBC survival –> haemolysis

208
Q

What types of anaemia do pyruvate kinase and G6PD def. display?

A

Macrocytic/haemolytic

209
Q

What is the presentation of pyruvate kinase def.?

A

Anaemia

210
Q

How do you diagnose pyruvate kinase def?

A

blood film (distorted prickle cells + reticulocytosis) and enzyme assay

211
Q

What is the difference between pyruvate kinase def. and G6PD def. in terms of treatment?

A

Splenectomy in pyruvate kinase def.

212
Q

Why does chronic haemolytic anaemia lead to folate deficiency?

A

folate is needed to make RBCs and therefore in haemolytic anaemia there is ^ demand to make more RBCs (depleting folate stores)

Phase 2a Haematology (1 decks)

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