Intro to Haematology Flashcards
(27 cards)
Name the components and products of blood
- Plasma: clotting/coagulation factors, albumin and antibodies
- Buffy coat: platelets and WBCs
- RBCs
What are the functions of blood?
- Transport: gases (in RBCs), nutrients, waste and messages (in plasma)
- Prevention of leaks (platelets and clotting factors
- Prevention of blockages: anticoagulants and fibrinolytics
- Protection from pathogens
Describe the 3 main pathogenesis of haematological abnormalities
- High levels: increased rate of production and decreased rate of loss
- Low levels: decreased rate of production and increased rate of loss
- Altered function
Describe the process of erythroid differentiation
- Erythroblast > reticulocyte > erythrocyte
- Erythropoietin: made in the kidney in response to hypoxia
What does a reticulocyte count measure?
Red cell production
What is polycythaemia?
Too many red blood cells
What are the potential consequences of anaemia?
- Poor gas transfer
- Dyspnoea
- Fatigue
What is the function of platelets and how are they produced?
- Haemostasis and immune response
- Production is regulated by thrombopoietin
- Produced in the liver
- Regulated by platelet mass feedback
- Agonists (romiplostim, eltrombopag) are used therapeutically
- Lifespan is 7 days
How can platelet function go wrong?
- Thrombocytosis - too many platelets produced
- Thrombocytopenia - too little platelets
- Altered function: antiplatelets
What are the functions of neutrophils?
- To ingest and destroy pathogens, especially bacteria and fungi
- Interleukins and colony stimulating factors
- Regulation by immune responses (macrophages, IL-17)
Name the five stages of neutrophil differentiation
1) Blast (acute myeloid leukaemia) neutrophil
2) Promyelocyte
3) Myelocyte
4) Metamyelocyte
5) Neutrophils
What are the causes of neutrophilia?
- Regulated by G-CSF
- Infection
- Inflammation
- Therapeutic use of G-CSF for neutropenia and mobilisation of stem cells
What are the causes of neutropenia?
- Decreased production: drugs and marrow failure
- Increased consumption: sepsis and autoimmune
- Altered function e.g. chronic granulomatous disease
What are the functions of monocytes?
- To ingest and destroy pathogens (esp. bacteria and fungi)
- Subset migrates into tissues and become macrophages or dendritic cells
What role do eosinophils have?
Plays a role in the immune response to parasites and in allergy
What are the causes of lymphocytosis?
- Infective mononucleosis
- Pertussis
What are the causes of lymphopenia?
- Usually post viral
- Lymphoma
What are the three types of lymphocytes?
- B cells
- T cells
- NK cells
Where are lymphocytes produced and where do they mature?
- Produced in the bone marrow
- B cells mature in the bone marrow
- T cells mature in the thymus
Describe the features of a T cell receptor
- Alpha chain (variable region)
- Beta chain (constant region)
Describe the features of a B cell receptor
- Light chain (variable region)
- Heavy chain (constant region)
Describe the different types of HLA
- Class I: displays internal antigens on all nucleated cells
- Class II: displays antigens eaten by professional antigen presenting cells
What are the normal interval ranges for haemaglobin?
- Male: 135-170 g/L
- Female: 120-160 g/L
What is the normal interval range for platelets?
150-400 10^9/L
