1. The Scope of Haematology Flashcards
What does Haematology Involve?
The Investigation / Management of Disorders of Blood and Bone Marrow
What are the Blood Components and Products?
- Plasma - Coagulation Factors / Albumin / Antibodies
- Buffy Coat - Platelets / Leucocytes
- Red Blood Cells
Note - This is going down a Test-Tube after it has been Centrifuged
What are the Functions of Blood?
- Transport
- Maintenance of Vascular Integrity
- Protection from Pathogens
What is Transported in the Blood?
- Gasses (O2 and CO2) - In Red Cells
- Nutrients - In the Plasma
- Waste - In the Plasma
- Messages - In the Plasma
What is involved in the Maintenance of Vascular Integrity?
- Prevention of Leaks - Platelets and Clotting Factors
2. Prevention of Blockages - Anticoagulants and Fibrinolytics
How does the Blood Protect against Pathogens?
- Phagocytosis and Killing - Granulocytes / Monocytes
2. Antigen Recognition and Antibody Formation - Lymphocytes
What is the Pathogenesis of Haematological Abnormalities?
- High Levels - Increased Rate of Production / Decreased Rate of Loss
- Low Levels - Decreased Rate of Production / Increased Rate of Loss
- Altered Function
What are the Features of Stem Cells?
- Totipotent
- Self-Renewable
- Home to Marrow Niche
- Binary Fission and Flux through Differentiation Pathways
Note - Stem Cell Properties can now be Induced
What is the Differentiation Pathway of the Pluripotent Haematopoietic Stem Cell?
Pluripotent Haematopoietic Stem Cell Splits:
- a) Lymphocyte Stem Cells - LYMPHOCYTE
- b) Uncommitted Stem - Committed Progenitor Cell
- Committed Progenitor Cell - :
- a) Erythroblast - Reticulocyte - ERYTHROCYTE
- b) Megakaryocyte - PLATELETS
- c) NEUTROPHIL
- d) MONOCYTE
- e) BASOPHIL
- f) EOSINOPHIL
What are the Red Blood Cells?
Erythrocytes
What are the Myeloid Cells?
Anything from the Committed Progenitor Cells:
- Erythrocytes
- Platelets
- Neutrophils
- Monocytes
- Basophils
- Eosinophil
What are the Lymphoid Cells?
- Neutrophil
- Monocyte
- Basophil
- Eosinophil
- Lymphocyte
When / Where is Erythropoietin made?
It is a Glycoprotein Cytokine made in the Kidney in response to Hypokia
What is a Reticulocyte Count?
A Measure of Red Cell Production
What is Polycythaemia?
Abnormally Increased Concentration of Haemoglobin in the Blood
What are the Causes of Anaemia?
- Decreased Production - Deficiency in Haematinics (Iron / Folate / Vitamin B12) / Thalassaemia
- Increased Loss - Bleeding / Haemolysis
What are the Consequences of Anaemia?
Poor Gas Transfer - Dyspnoea / Fatigue
What are the different Disorders of Red Blood Cells?
- Microcytes
- Macrocytes
- Polychromasia
- Burr Cells
What are the Features of Platelets?
- Haemostasis (and Immune) Function
- Production is Regulated by Thrombopoietin in the Liver
- Lifespan = 7 days
When are Platelets involved in Pathology?
- Thrombocytosis - Body Makes Too Many Platelets
- Thrombocytopenia - Platelet Deficiency (Bleeding)
- Altered Function - Due to Aspirin / Clopidogrel etc.
What is the Features of Neutrophils?
- Their Function is to Ingest and Destroy Pathogens, especially Bacteria and Fungi
- Exist as Interleukins and Colony Stimulating Factors
- Immune Response Regulated - Macrophages / IL-17
- Lifespan = 1-2 Days
What is Neutrophil Differentiation?
- Blast
- Promyelocyte
- Myelocyte
- Metamyelocyte
- Neutrophil
When does
- Neutrophilia occur?
- Neutropenia occur?
- Infection / Inflammation
- Abnormally low levels of White Blood Cells:
- a) Decreased Production - Drugs / Marrow Failure
- b) Increased Consumption - Sepsis / Autoimmune
- c) Altered Function - Chronic Granulomatous Disease
What are the Features of Monocytes?
- Their Function is to Ingest and Destroy Pathogens, especially Bacteria and Fungi
- Monocytes Migrate into Tissues and Become Macrophages - the Reticuloendothelial System
When does Monocytosis occur?
Mycobacterial Infection
Note - usually associated with Neutrophilia
When does Monocytopenia occur?
Mycobacteria in Hairy Cell Leukaemia
When are Eosinophils Activated?
- Parasitic Infection
2. Allergy
What are the Features of Lymphocytes?
- Part of the Adaptive / Innate Immune System
- Exist as B-Cells / T-Cells / NK Cells
- Produced in the Bone Marrow
- Circulates in Blood, Lymph and Lymph Nodes
- Differentiate into Effector Cells in Secondary Lymphoid Organs
When does
- Lymphocytosis occur?
- Lymphopenia occur?
- Infectious Mononucleosis / Pertussis
2. (Usually) Post-Viral / Lymphoma
What are the Features of T and B Cells?
Each naive T and B Cell has a Unique Surface Receptor
