Introduction to Haematology (Haematology pathology) Flashcards
What is haematology?
Biology and pathology of cells that normally circulate in the blood
What is Haemopoises?
The process that gives rise to cell in blood
1 stem cell can divide and differentiate.
What are the haemopoietic lineages?
1) Myeloid
e. g. WBC/RBC/Platelets
2) Lymphoid
e. g. B cells /T cells
What day during development does haemopoiesis start?
Day 27
What is the function of blood cells?
- Oxygen transport
- Coagulation
- Immune response to pathogens
- Immune response to abnormal cells
What is the life span of Red Blood Cells?
120 days
What is the term for reduced / raised RBC count.
Reduced RBC = anaemia
Raised RBC= Polycythaemia
What are granulocytes?
Granulotcytes are WBCs that have cytoplasmic granules and are specialised into :
1) Neutrophils
2) Eosinophils
3) Basophils
What are neutrophils?
WBC > Granulocyte > phagocyte.
Most common WBC.
-fights bacterial infection.
What are eosinophils?
WBC > Granulocytes
- fights parasitic infection
- allergic reaction
What are monocytes?
Phagocytic and antigen presenting cells.
They migrate to tissues and are then known as macrophages of histiocytes.
What are Natural killer cells?
NK cells are large lymphocytes that are part of the innate immune system.
What are B-Lymphocytes?
they are part of the adaptive immune system.
Produce antibodies
What are T Lymphocytes?
T Lymphocytes are part of the adaptive immune system.
They are cell mediated immunity.
What is Lymphocytosis?
Lymphocytosis is increased numbers of lymphocytes
What is lymphopenia?
Lymphopenia is decreased numbers of lymphocytes
Where are platelets derived from?
Platelets are derived from bone marrow megakaryocytes
What does a full blood count measure?
1) Haemoglobin concentration
2) Red cell parameters (mean cell volume and mean cell haemaglobin)
3) White Cell count
4) Platelet count
What is a coagulation screen?
It is a test that measures the time taken for a clot to form when plasma is mixed with specified reagents.
1) Prothrombin time
2) Activated partial thromboplastin time
3) Thrombin time
What is the difference between sensitivity and specificity?
Sensitivity : proportion of ABNORMAL results correctly classified by test. (ability to detect a true abnormality)
Sensitivity = TP/(TP+FN)
SPECIFICITY:
-proportion of NORMAL results correctly classified by the test. (ability to exclude an abnormal result in a healthy person)
Specificity = TN / (TN+FP)
What is Microcytic Hypochromic Anaemia?
What are the causes?
Microcytic Hypochromic Anaemia : Small, Pale Red blood cells.
Causes:
- Iron deficiency,
- Thalassaemia,
- anaemia of chronic disease,
- lead poisoning
- sideroblastic anaemia.
What is normocytic normochronic anaemia?
Whar are the causes of normocytic normochronic anaemia?
normocytic = decreased haematocrit / haemoglobin Normochromic = decreased RBC count
Caused by:
- haemolytic anaemia
- anameia after chronic disease
- after acute blood loss
- renal disease
- bone marrow failure
What is macrocytic anaemia?
Large RBCs
causes:
Vit B12 or Folate defiency
liver disease
What are the characteristics of iron deficiency anaemia?
-Small pale RBC
-variable shape (long thin)
(low mean cell volume (MCV) and low mean cell haemaglobin (MCH) )
What are the characteristics of Vitamin B12 Deficiency ?
Hypersegmented neutrophils and oval macrocytes
What is the normal haemaglobin range for men and women?
Haemaglobin
men = 135 - 180
women = 115 -160
what is the normal range for WBCs?
4 - 11
What is the normal range for platelets?
150 -400 X10^9/L
What is the normal mean cell volume?
78 - 100 fL
What is the normal red blood cell count in men and women?
RBCs
Men = 4.5-6.5
women = 3.8-5.8
What is the normal neutrophil count?
2.0 - 7.5
