Introduction to Haematology Flashcards
The physiological development process that gives rise to the cellular components of the blood.
Haemopoiesis
What are the 4 forms of self-renewal that a haematopoietic stem cell can undergo
Symetrical self-renewal
Asymetrical self renewal
Lack of self-renewal (2xP)
Lack of self-renewal
What type of self renewal increases the stem cell pool?
Symetrical self renewal
What type of self renewal maintains the stem cell pool and generates differentiated progeny?
Asymetrical self-renewal
What type of self-renewal depletes the stem cell pool and only generates differentiated progeny
Lack of self renewal
What are the 2 haematopoietic lineages
Myeloid
Lymphoid
At day 27, haemopoiesis starts where?
Aortagonad mesonephros region
At day 40, haematopoietic stem cells migrate where?
Foetal liver
Life span of erythrocytees
120 days
low RBCs
Anaemia
high RBCs
Polycythaemia
When plasma vol. is low and high conc of RBCs
Relative polycythaemia
What are the 2 major groups of leukocytes
Granulocytes (myeloid)
Lymphocytes (lymphoid)
Most common WBC
Neutrophils
Lifespan of neutrophils
A few hours
Increased numbers of neutrophils, when might this happen?
Neutrophilia e.g. infection, inflammation
Decreased numbers of neutrophils, when might this happen?
Neutropenia e.g. side effect of a drug
A rare WBC, part of the primative immune system
Basophils
Describe the differentiation of monocytes
Migrate to tissues and are then identified as macrophages. (histiocytes e.g. kupffer cells in liver, langerhans cells in skin)
Increased numbers of monocytes, when might this happen
Monocytosis e.g. TB
3 types of lymphocytes
Natural killers
B Lymphocytes
T lymphocytes
Innate immune system, large granular lymphocytes that recognise ‘non self’
Natural killers
Lymphocytes associated with humoral immunity
B cells
Lymphocytes associated with cell-mediated immunity
T cells
Examples of when you might get lymphocytosis
Glandular fever, chronic lymphocytic leukaemia
Examples of when you might get lymphopenia
Post bone marrow transplant
Platelets are derived from what cell?
Megakaryocytes
Normal Hb concentration
115-175g/L
Normal RBC concentration
4-6.5x1012/L
Normal WBC concentration
4-11x109/L
Normal MCV
80-100
Normal MCH
27-33
What does the FBC test
Concentration of Hb
MCV, MCH
White cell count
Platelet count
3 examples of coagulation screens
Prothrombin time
Activated partial thromboplastin time
Thrombin time
Liquid marrow is aspirated from posterior iliac crest of pelvis. Trephine core biopsy
Bone marrow aspirate and trephine
The set of values for a given test that incorporates 95% of the population
Reference range
MCV
Microcytic hypochromic anaemia
Causes of microcytic hypochromic anaemia
Iron deficiency
Thalassaemia
Anaemia of chronic disease
lead poisoning
MCV 80-95
MCH > 27
low serum iron
Normocytic normochromic anaemia
Causes of normocytic normochromic anaemia
Haemolytic anaemias Anaemia of chronic disease After acute blood loss Renal disease Mixed deficiencies Bone marrow failure
MCV>95
Can be megaloblastic or non megaloblastic
Macrocytic anaemia
Abnormally large, immature, and dysfunctional red blood cell, sometimes seen in macrocytic anaemia
Megaloblastic
Causes of macrocytic megaloblastic anaemia
Vit B12 or folate deficiency
Causes of non megaloblastic macrocytic anaemia
Alcohol, liver disease, myelodysplasia, aplastic anaemia etc
Haematological findings of iron deficiency
Low MCV and MHC. Small pate RBCs, variable size and shape. Lon, thin ‘pencil’ cells
Haematological findings of vit B12 deficiency
RBCs much bigger. Hypersegmented neutrophils and oval macrocytes
Reduced levels of serum iron, MCV and MCH are within the normal ranges
Norcocytic, normochromic anaemia
Describe the pathology of megaloblastic macrocytic anaemia
B12/folate deficiency- RBCs can’t synthesise DNA quick enough to divide at the right point in their growth, so cells are abnormally large and MCV and MCH are low