Anaemia Flashcards
1
Q
What does PCV stand for? What else is it known as? What does it mean?
A
Packed cell volume
Haemocrit
Volume percentage of RBCs in blood.
2
Q
What Is normal haemocrit/PCV in:
Men?
Women?
A
45% men
40% women
3
Q
What are the 3 most common symptoms of anaemia?
A
Fatigue, faintness, breathlessness
4
Q
What 2 symptoms can people experience when anaemia exists alongside atheromatous arterial disease?
A
Angina pectoris
Intermittent claudication
5
Q
What are normal Hb levels for:
Males?
Females?
A
Males: 13.5 - 17.5
Females: 11.5 - 16
6
Q
What does MCV stand for? What is it?
A
Mean corpuscular volume
- the mean red blood cell size
7
Q
Why does microcytosis come about? How does it appear on a blood film?
A
Decreased Hb content within the RBC
Hypochromic
8
Q
What are the 4 main causes of microcytic anaemia?
A
Iron deficiency
Anaemia of chronic disease
Thalassaemia
Sideroblastic anaemia
9
Q
Why is iron related to anaemia?
A
It is necessary for the formation of haem
10
Q
How much iron is absorbed from the diet?
A
10%
11
Q
Where in the GI tract is iron absorbed?
A
Duodenum
12
Q
Name 3 factors that increase intestinal iron absorption?
A
Gastric acid
Iron deficiency
Increased erythropoietic activity
13
Q
Where is non haem iron found in the diet? (2)
A
Vegetables
Fortified cereals
14
Q
Where is haem iron found?
A
Derived from haemoglobin and myoglobin in red or organ meats
15
Q
Of haem and non-haem iron, which is better absorbed?
A
Haem iron
16
Q
How is iron transported in the blood?
A
Transferrin
17
Q
Where is transferrin synthesised?
A
Liver
18
Q
How is the body’s iron incorporated into haemoglobin
A
In developing erythroid precursors and mature red cells
19
Q
How is body irod stored?
A
As ferritin and haemosiderin in hepatocytes, skeletal muscle and reticuloendothelial macrophages
20
Q
What are the 4 main reasons for iron deficiency?
A
Blood loss (most common) - e.g. menorrhagia or GI bleeding
Incr demands - eg. growth and pregnancy
Decreased absorption - eg. small bowl disease or post gastroctomy
Poor intake
21
Q
What is the most common cause of iron deficiency worldwide?
A
Hookworm = intestinal blood loss
22
Q
What are normal MCV values?
A
80 - 96
23
Q
What does MCH stand for? What is it?
A
Mean corpuscular haemoglobin
Average mass of haemoglobin per RBC
24
Q
What do ferritin levels represent?
A
Iron stores
25
When might ferritin levels be normal despite the presence of iron deficiency?
Inflammatory or malignant disease, it is an acute phase reactant
26
What will the total iron-binding capacity be in iron deficiency?
High
27
How do you work out transferrin saturation?
Serum iron/TIBC
28
What is the transferrin saturation in iron deficiency anaemia?
<19%
29
In anaemia of chronic disease:
- What happens to the serum iron-binding capacity?
- What is the MCV?
- What is the MCH?
- Serum ferritin levels?
- Low
- Normocytic or microcytic
- Normochromic
- Normal or increased (NB - acute phase reactant)
30
Name 5 chronic conditions in which anaemia might occur
```
Crohn's
RA
(chronic infections): TB
Malignancy
Chronic kidney disease
```
31
Why does sideroblastic anaemia come about?
There is impaired utilisation of iron delivered to developing erythroblasts
32
What is sideroblastic anaemia characterised by? (3)
- refractory anaemia
- hypochroic cells in peripheral blood
- ring sideroblasts in the BM
33
Sideroblastic anaemia may be inherited, alternatively it may be acquired - how? (4)
Myelodysplasia (ineffective production of blood cells)
Alcohol excess
Lead toxicity
Isoniazid
34
What is the first investigation to order in macrocytotic anaemia.
Serum B12 measurement and red cell folate
35
What are the 2 subdivisions of macrocytic anaemia? How is it determined?
Megaloblastic
Non-megaloblastic
Examination of the bone marrow
36
What do lymphoid stem cells give rise to?
Pre T cells (which become T suppressor, T helper, NK cells)
| Pre B cells (which become B cells and plasma cells)
37
What do mixed myeloid progenitor cells give rise to?
Units for production of RBCs, platelets, monocytes, neutrophils, eosinophils, basophils
38
Name 4 factors that stimulate production from mixed myeloid progenitor cells? Where do each come from?
Erythropoietin (RBCs)
Thrombopoietin (platelets)
Neutrophils (granulocyte colony stimulating factor/G-CSF)
IL 5 (eosinophils)
39
Name a factor that inhibits production from mixed myeloid progenitor cells?
TNF
40
What are reticulocytes?
Young red cells released form the BM, they still contain RNA
41
What size are they in relation to RBCs? And what proportion of circulating RBCs do they normally represent?
Larger
| 0.5-2.5%
42
What is the reticulocyte count a measure of?
Erythroid activity in the bone marrow
43
When is there an increase in the reticulocyte count?
Haemmorhage, haemolysis, treatment with haematinics
44
# Fill the gaps:
Megaloblastic anaemia is characterised by the presence in the __ __ of developing __ __ __ with delayed __ maturation relative to that of the __.
Bone marrow
Red blood cells
Nuclear
Cytoplasm
45
What is the mechanism underlying megaloblastic anaemia?
Defective DNA synthesis
46
What else does the defective DNA synthesis underlying megaloblastic anaemia affect?
White cells
| Platelets
47
How might the neutrophils appear in megaloblastic anaemia? And the platelets?
```
Hypersegmented
Thrombocytopenia (decr platelet count. NB - thrombocytes = platelets)
```
48
What are the two most common forms of megaloblastic anaemia? Why?
Vitamin B12, folate
| They are necessary for DNA synthesis
49
Where in the diet is B12 found?
Meat and dairy (especially red meat)
50
Where is B12 absorbed?
Terminal ileum
51
Where is B12 stored in the body? How long would the supply last?
Liver
| 2+ years
52
What is the most common cause of B12 deficiency in the western world?
Pernicious anaemia
53
What is pernicious anaemia?
Autoimmune condition where this atrophic gastritis = loss of parietal cells and failure of intrinsic factor production and malabsorption.
54
What are the 3 main causes of B12 deficiency?
```
Low dietary intake (vegans)
Impaired absorption (stomach: pernicious anaemia, post gastrectomy, and terminal ileum: ileal resection, Crohn's)
Abnormal utilisation
```
55
What effect does nitrous oxide have on B12?
Inactivates it
56
What are the neurological symptoms of B12 deficiency?
Polyneuropathy caused by symmetrical damage to the peripheral nerves and posterior and lateral columns of the spinal cord.
57
How will posterior and lateral spinal cord damage present?
Progressive weakness, ataxia and eventually paraplegia.
| Dementia and visual disturbances due to optic atrophy.
58
What are the clinical features of anaemia?
Conjunctival pallor
| Signs of hyper dynamic circulation e.g. tachycardia, flow murmurs, cardiac enlargement, retinal haemorrhage
59
What are the values for anaemia?
Hb levels -
< 135g/L (men)
< 115g/L (women)
60
Why does anaemia sometimes occur in pregnancy?
Incr plasma volume
61
When should you suspect thalassaemia?
Microcytic anaemia, when MCV is 'too low' for Hb level.
62
In both sideroblastic anaemia and thalassaemia, how will each of the following appear: And why?
Serum Iron
Ferritin
TIBC
Incr
Incr
Low
In these conditions there is an accumulation of iron
63
Name 7 causes of normocytic anaemia
```
Acute blood loss
Anaemia of chronic disease
BM failure
Renal failure
Hypothyroidism
Haemolysis
Pregnanacy
```
64
What should each of the following be to suspect haemolytic anaemia?
Reticulocytosis levels?
Bilirubin?
Both high
65
What drug should you give alongside a blood transfusion?
Furosemide
66
What are the clinical signs of IRON deficiency anaemia? (4 - but 3 important ones)
Koilonychia
Atrophic glossitis
Angular cheilosis
Post-cricoid webs (Plummer-Vinson syndrome)(upper oesophageal webs)
67
What is the MCV of iron deficient anaemia?
Decreased
68
In anaemias of chronic disease, what are the 3 problems?
Poor use of iron in erythropoiesis
Cytokine-induced shortening of RBC survival
Decr production of and response to erythropoietin
69
When should you think about sideroblastic anaemia?
When microcyctic anaemia is not responding to iron.
70
What is the most common reason for macrocytosis? (without accompanying anaemia)
Alcohol excess
71
Which of red cell folate and serum folate is a more reliable indicator of folate status? Why?
Red cell folate
| Serum folate on reflects recent intake
72
Where is folate found in the diet? (4)
Green vegetables
Nuts
Liver
Folate
73
What does maternal folate deficiency cause?
Neural tube defects (spina bifida)
74
Which drugs can cause folate deficiency?
Anti-epileptics
Methotrexate
Trimethoprim
75
Where is folate absorbed?
Duodenum/prox jejunum
76
Why should never give folate without B12 unless it is know that B12 levels are normal?
Can precipitate/worsen subacute combines cord degeneration
77
What should you give before you give folate supplements? Mem aid?
B12 must be given before folate (unless B12 levels known to be normal).
B is before F in the alphabet
78
What are the general clinical signs of B12 deficiency?
Anaemia signs
| Angular cheilosis/stomatitis, glossitis, 'lemon skin' - due to pallor + mild jaundice
79
What are the neuropsychiatric signs of B12 deficiency? (4)
Irritability
Depression
Psychosis
Dementia
80
What are the neurological signs of B12 deficiency?
Parasthesiae
Peripheral neuropathy
Subacute combined degeneration of the spinal cord
81
What is subacute combined degeneration of the spinal cord?
Combination of:
Dorsal column loss = sensory and LMN signs
+
Symmetrical corticospinal tract loss = motor and UMN signs
82
In subacute combined degeneration of the spinal cord, which sense goes first?
Vibration and proprioception, leads to ataxia, then stiffness, weakness.
Eventually paraplegia.
83
What is the classic triad of neurological symptoms seen in B12 deficiency? Are each of these associated with upper or lower motor neurone problems?
Extensor planters (UMN), absent knee jerks (LMN), absent ankle jerks (LMN).
84
In B12 deficiency, which 2 sensations remain in tact? Why?
Pain and temperature.
| Spinothalamic tracts are not damaged
85
Can neurological B12 deficiency signs occur without anaemia?
Yes
86
What does B12 deficiency often present as? Why?
Nighttime falls - due to vision loss (optic atrophy) and ataxia
87
How do you treat B12 deficiency initially?
Hydroxocobalamin IM
88
What levels do you need to watch while a patient is on hydroxocobalamin?
K+
89
In B12 deficiency anaemia, what will you see in the marrow?
Megaloblasts
90
In B12 deficiency anaemia, what will the levels of reticulocytes be?
Decr or normal as production impaired
