Intro to Haemotology Flashcards
1
Q
What are the 3 blood components?
A
Plasma
Buffy coat
RBCs
2
Q
What is found in plasma?
A
Clotting or coagulation factors
Albumin
Antibodies
3
Q
What is found in the buffy coat?
A
Platelets
White cells or leucocytes
4
Q
Functions of the blood
A
Transport (RBCs and plasma)
Maintenance of vascular integrity
Protection from pathogens
5
Q
What is transported in red cells?
A
Gases - CO2 and O2 (haem binding to these)
6
Q
How is vascular integrity maintained by the blood?
A
Prevention of leaks
- platelets and clotting factors
Prevention of blockages
- anticoagulants and fibrinolytics
7
Q
How does the blood protect from pathogens?
A
Phagocytosis and killing
- granulocytes/monocytes
Antigen recognition and antibody formation
- lymphocytes
8
Q
Abnormally high levels in the blood is due to either…
A
Increased rate of production
Decreased rate of loss
9
Q
Abnormally low levels in the blood is due to either…
A
Decreased rate of production
Increased rate of loss
10
Q
Where do all cells in the blood come from?
A
Uncommitted stem cells
11
Q
Haematopoiesis definition
A
the commitment and differentiation processes that lead to the formation of all blood cells from haematopoietic stem cells
12
Q
Another name for RBCs
A
Erythrocytes
13
Q
Another name for WBCs
A
Leucocytes
14
Q
What are myeloid cells?
A
Everything apart from lymphocytes
15
Q
What type of stem cells form other types of cells outwith the blood?
A
Mesenchymal stem cells
16
Q
Features of stem cells
A
Totipotent
Self renewal
Home to marrow niche (CXCR4)
properties can now be induced
17
Q
How are stem cell numbers amplified?
A
Binary fission and flux through differentiation pathways
18
Q
What is the flux of stem cells regulated by?
A
Hormones/growth factors
19
Q
Where is bone marrow found?
A
Bone marrow
- mostly in children
- axial in elderly
20
Q
Examples of RBCs pathologies
A
Polychromasia
Polycythaemia
21
Q
Polychromasia definition
A
Abonormally high number of immature RBCs
22
Q
Polycythaemia definition
A
Abnormally high number of haemoglobin in the blood
23
Q
Differentiation stages of RBCs
A
Erythroblast - > reticulocyte - > erythrocyte
24
Q
When is erythropoietin made and where?
A
Made in the liver in response to hypoxia
25
What does the reticulocyte count measure?
A measure of Red cell production
26
Consequences of anaemia
Poor gas transfer
Dyspnoea
fatigue
27
Causes of anaemia
Decreased production
- deficiency in haematinics (iron, folate, vitamin B12)
- congenital (thalassaemias)
Increased loss
- bleeding
- haemolysis
28
What make up the most common haematinics?
Iron
Folate
Vitamin B12
29
What are platelets produced by?
Marykaryocytes
30
Function of platelets
Haemostasis
| Immune
31
What is the production of platelets regulated by?
Thrombopoietin
32
Regulation of platelet production
Thrombopoietin regulates it
Produced in liver
Regulation by platelet mass feedback (agonists - romiplostim can be used therapeutically)
33
Lifespan of platelets
7 days
34
Pathologies of platelets
```
Thrombocytosis
Thrombocytopenia
Altered function
- aspirin
- clopidogrel etc
```
35
Features of thrombocytosis
Reactive - goes away when underlying disease resolves
36
Thrombocytosis definition
Excessive number of platelets in the blood
37
Thrombocytopenia definition
Abnormally low level of platelets in the blood
38
Thrombocytopenia causes
Marrow failure
| Immune destruction
39
Function of neutrophils
To ingest and destroy pathogens, especially bacteria and fungi
40
Function of neutrophils is controlled by what?
Interleukins
| CSFs (colony stimulating factor)
41
Lifespan of neutrophils
1-2 days
42
speed of response of neutrophils
a few hours
43
Regulation of neutrophils is by....
Immune responses
- macrophages
- IL-17
44
Differentiation of neutrophils
```
Blast (acute myeloid leukaemia)
Promyelocuye
Myelocyte
Metamyelocyte
neutrophil
```
45
What are neutrophils full of?
Enzymes
| Granules
46
Definition of neutrophilia
Increased number of neutrophils
47
What is production of neutrophilia regulated by?
granulocyte colony stimulating factor (G-CSF)
48
Causes of neutrophilia
```
Infection
- left shift
- toxic granulation
Inflammation
- E.g. MIR, post op, RA
```
49
When would G-CSF be used therapeutically?
Neutropenia
| Mobilisation of stem cells
50
Neutropenia definition
Low levels of neutrophils in the blood
51
What does neutropenia vary with?
race
52
Causes of neutropenia
```
Decreased production
- drugs (mainly cytotoxic drugs)
- marrow failure
Increased consumption
- sepsis (neutrophils go to septic tissue)
- autoimmune
Altered function
- chronic granulomatous disease
```
53
Function of monocytes
To ingest and destroy pathogens especially bacteria and fungi but not as important as neutrophils for this
Migrate to tissues and become macrophages
54
Lifespan of monocytes/macrophages
Many months
55
Dendritic cells lifespans
Weeks
56
Eosinophils are important in the fight against.....
Parasites
| Allergies
57
Features of lymphocytes
Adaptive vs Innate immune system
| CD markers as surface antigens
58
Definition of lymphocytosis
Increased number of lymphocytes in the blood
59
Causes of lymphocytosis
Infectious mononucleosis
| Pertussis
60
Definition of lymphopenia
Abnormally low levels of lymphocytes in the blood
61
Causes of lymphopenia
Usually post viral
| Lymphoma
62
Subtypes of lymphocytes
B cells
T cells
NK cells
63
What do B cells do?
make antibodies or are precursor cells to make antibodies
64
Types of T cells
Helper
Cytotoxic
Regulatory
65
What do helper T cells do?
Help to regulate the immune system
66
What do cytotoxic T cells do?
Kill foreign pathogens that the T cell recognises
67
What do Regulatory T cells do?
Help to dampen down the immune system
68
Where are lymphocytes produced?
Bone marrow
69
Where do the lymphocytes mature?
B cells mature in bone marrow
| T cells mature in thymus
70
Where do lymphocytes circulate?
Blood
Lymph
Lymph nodes
71
Where do lymphocytes differentiate into effector cells?
Secondary lymphoid organs
72
What is a secondary lymphoid organ?
Lymph nodes
| Mucosal associated lymphoid tissue
73
Regions of Lymphocytes
Variable region
| Constant region
74
Function of antibodies
Adaptors between pathogens and clearance systems
75
Method of antibodies
Opsonisation
Fix complement (punching holes in pathogens)
Block binding
76
Types of repertoire diversity
Combinatorial (within each chain)
| Junctional (at join, additional nucleotides added)
77
Mistakes in repertoire diversity chains can lead to what?
Lymphoid malignancies
78
What chains pair in combinatorial diversity?
Alpha chain pairs with beta chains
| Each light chain pairs with a heavy chain
79
Positive vs negative selection
Positive selection = gene rearrangement resulting in a functional receptor so the cell is selected to survive. B cells that survive this are exported to the periphery
Negative selection = if bad gene or if the receptor recognises 'self-antigens' then the cells will be triggered to die = TOLERANCE
80
What does HLA stand for?
Human Leucocyte Antigen
81
Classes of HLA
Class I; displays internal antigens on all nucleated cells
| Class II; displays antigens eaten by professional antigen presenting cells
82
Which cells is HLA made in?
Every single cell apart from Red cells
83
What does HLA do?
Immune cells read HLA-barcode on cells to help identify self vs non self cells or uninfected vs infected cells
84
What causes too much plasma?
Paraproteins
85
What causes too little plasma?
Clotting factors
86
What causes abnormal function of plasma?
Haemophilia
87
What can RA cause in the blood?
```
Anaemia of chronic disease
Iron deficiency
Folate deficiency
immune haemolysis
neutrophilia
Immune thrombocytopenia
cytopenias secondary to medication
felty syndrome
```
88
What can hepatic disease cause in the blood?
Anaemia
| Deficient clotting factors
89
What can renal disease cause in the blood?
Anaemia
| Haemolytic uraemia syndrome
90
What can respiratory disease cause in the blood?
Polycythaemia
91
Diagnostic tools of the blood
```
FBC
Clotting times (clotting factors)
Bleeding times (platelets)
Platelet and leucocyte function tests
Chemical assays (iron (ferritin), B12, folate)
Marrow aspirate and trephine biopsy
Lymph node/other organ biopsy
Imaging (CT - angiograms)
```
92
Normal blood values for haemoglobin
Male 135-170 g/L
| female 120-160 g/L
93
Normal blood vales for platelets
150-400 x109/L
94
Normal blood values for WBC
4-10 100/L
95
Haematology treatments
```
Replacement
- blood
- haematinics
- coagulation factors
- plasma exchange
Transplantation
Drugs
- cytotoxic
- monoclonal antibodies
- inhibitors of cellular proliferation
- immunosuppressants
- inhibitors of coagulation
- inhibitors of fibrinolysis
```
96
Types of pulp of the spleen
```
Red = where blood cells go to mature
White = important for immune function
```
97
Hypersplenism causes
Pancytopenia
98
Definition of pancytopenia
Deficiency of all 3 cellular components of the blood (RBCs, white cells and platelets)
99
Causes of hyposplenism
Infections with encapsulated bacteria
| Red cell changes
100
Causes of splenomegaly
```
Infection
- acute = EBV, CMV
- chronic bacterial e.g. TB, brucella
- chronic parasitic e.g. malaria
Haematological malignant
- leukaemias and lymphomas
- myeloproliferative disorders
Portal hypertension
Haemolytic disorders (autoimmune, megaloblastic anaemia, hereditary spherocytosis)
Connective tissue disorders
-SLE
- Felty syndrome
Sarcoid
Malignancy
Amyloid
Storage pool disorders (Gauchers)
```
101
When would neutrophils be increased?
Acute inflammation
Burns
Malignancy
102
When would neutrophils be decreased?
Decreased production e.g. aplastic anaemia
| Increased destruction e.g. chemo
103
Causes of lymphocytosis
Infection
| Lymphoma
104
Causes of lymphopenia
HIV
| Leukaemia
105
Causes of increased monocytes
Infection
- bacterial
- chronic infection
- sarcoid
106
Causes of decreased monocytes
Bone marrow failure
| Medications e.g. chemo / steriods
107
Causes of increased eosinophils
Allergic reaction
| Parasitic infection
108
Causes of decreased eosinophils
HIV / alcohol
109
Causes of increased basophils
Anaphylaxis
| Asthma
110
Causes of decreased basophils
Bone marrow failure
