Concepts in haematology Flashcards
In general why might cell counts be high or low ?
- A normal response (reactive) or
- An abnormal response (congential/acquired, malignancy? deficiency? Genetic?)
What are some of the general reasons why the cell count might be low ?
- Increased destruction
- Reduced production
- Redistribution
What are the general reasons why the cell count might be high?
- Increased production in response to stimulus
- Increased production with no stimulus intrinsic (malignancy)
- Redistribution
What is meant by cyotsis or philia are the end of something ?
- An excess of something
- Neutrophilia, thrombocytosis
- (caution though as thromophilia = excess clotting)
What does penia at the end of something mean ?
A shortage of e.g. Lymphopenia
Define hyperplasia
The enlargement of an organ or tissue caused by an increase in the reproduction rate of its cells
Define dysplasia
The presence of cells of an abnormal type within a tissue, which may signify a stage preceding the development of cancer.
Define hypoplasia
Inadequate or below-normal number of cells.
Define aplasia
The failure of an organ or tissue to develop or to function normally. (no production of cells)
Define homeostasis
The active regulation of a system to keep a constant level
What is the erythron ?
The red blood cells and their precursors in the bone marrow.
What happens to the raw materials of red blood cells once they have been broken down ?
They are recyclyed
What detects hypoxia in the blood and where does this detection occur ?
- Interstitial fibroblasts detect hypoxia in the blood
- This occurs near to the peritubular capillaries and the proximal convoluted tubule in the kidney
What physiological response does hypoxia (relative anaemia) result in ?
- Production of EPO from kidneys which then acts on the bone marrow
- Stimulates cell division of red cell precursors and recruits more cells to red cell production in the marrow
- The result is erythroid hyperplasia
