2. Introduction to Heamatology Flashcards
What is haematology?
The investigation of blood and bone marrow
The management of disorders of blood and bone marrow
What are the components of blood?
Red blood cells
Buffy coat- Platelets, White cells
Plasma- Clotting or coagulation factors, albumin, antibodies
What is the difference between plasma and serum
Plasma- contains clotting factors
Serum- has clotted, does not contain clotting factors
What is the function of the blood?
Transports:
- oxygen and carbon dioxide
- Nutrients
- waste
- messages
How does blood maintain vascular integrity?
Contains platelets and clotting factors, prevents leaks
Prevents blockages through anticoagulants and fibronocytes
How does the body protect from pathogens?
Phagocytosis and killing
Antigen recognition and antibody formation
How do you classify heamatological abnormalities?
Increased rate of production- High level
Deceased rate of loss- High levels
Decreased rate of produciton- Low levels
Increased rate of loss
What are myeloid cells?
All the cells coming out of the bone marrow
Erythrocytes, platelets, neutrophil, monocyte, basophils eosinophils, lymphocyte
What are stem cells?
Totipotent
Self renewal
Home to narrow niche e.g. CXCR4 (antagonist plerixafor)
Binary fission and flux through differntiation pathways amplify numbers
Flux regulated by hormones/growth factors
Discuss bone marrow
Most in children, axial in elderly
Contains stroma and sinusoids
Describe erythronium differentiation
Eryhtrobloast—-> reticulocyte—-> erythrocyte
Erythropoietin (made in kidney in response to hypoxia)
Reticulocyte count (a measure of red cell production)
What are the consequences of anaemia?
What are the heamatinics
What are the causes of aneamia
Poor gas transfer, dyspnoea, fatigue
Deficiency in “heamatinics”- iron, folate vitamin B12
Thalassaemias
Bleeding, haemolytic
What are the functions of platelets?
Where are they produced
How long do they last
Haemostasis and immune response
Production regulated by thrompoietin
Produced in Liver
Lifespan- 7 days
What diseases happen with platelets?
Thrombocytosis- too many platelets, spontaneous clots
Thrombocytopenia- too little platelets marrow failure, immune destruction
What is the job of neurtrophils?
Ingest and destroy pathogens especially bacteria and fungi
Lifespan 1-2 days, speed of response a few hours
How do neutrophils differentiate?
Blast (present in acute myeloid leukaemia)
Neutrophil
What is neutropenia?
What are it’s causes
Low neutrophil count,
caused by drugs, marrow failure, sepsis,autoimmune consumption, altered function e.g. chronic granulomatous disease
What are monocytes?
Ingest and destroy pathogen, especially bacteria and fungi
Subset of monocytes migrate into tissues and become macrophages or dendritic cells
Some macrophages are self maintaining
What are all the different names for monocytes
Langerhan cells- skin Kupifner cells- liver Lung alveolar macrophages Brain microglia serosal macrophages Sinus macrophages Spleen sinus macrophages
What are the other myeloid cells?
Eosinophils- fight parasites, double nucleated. Cause allergies
Basophils
What causes altered lymphocyte counts?
Lymphocytosis- infectious mononucleosis
Pertussis
Lymphopenia- usually post viral, lymphoma
What do the different T cells do?
Helper- assist immune response or cytotoxic cells
Cytotoxic- Kills cells that should not be there
Regulatory- prevent autoimmune disease
How are antibodies generated?
Each lymphocyte has one T or B cell receptor.
Variable regions are created by V-D-J recombination
Mistakes in the V-D-J recombination leads to malignancies due to oncogenes being incoparated into the process and then being matured
Describe the basic structure of antibodies.
Two heavy chains and two light chains to form a “Y” shape
Top bit is the FAB region
What are The different types of antibodies
IgG- main one IgE- immunity to parasites IgD- activates B cells IgM- generated early in immune response IgA- gut
What is the difference between type 1 and type two human leukocyte antigen (HLA or MHC).
Type 1- displays internal antigens of a cell on all nucleated cells
Type 2- displays antigens eaten by professional antigen presenting cells
Why is everyone with rhaemuatoid arthritis anemic?
Taking non steroidals tend to bleed Anaemia that occurs with chronic diseases Folate deficiency Immune heamolysis Neutrophilia Immune throbocytopenia Cytopenias secondary to medication
What abnormalities can occur with plasmas?
Too much- paraproteins
Too little- clotting factors- haemophilia
Abnormal function- clotting factors; haemophilia
What blood count normal ranges do you have to know?
Male heamoglobin- 135-170g/l
Female heamoglobin-120-160g/l
Platelets-150-400
White blood cell count-4-10
What other diagnostic tools are there?
Clotting times
Bone marrow and lymph biopsy
Chemical analysis- iron, B12, ferrate
Imaging
