Haematology summray 2

Chapter 2 in haematology (Erythropoiesis and general aspects of anaemia)summary

-Erythropoiesis (red cell production) is regulated by erythropoietin which is secreted by the kidney in response to hypoxia. Erythropoiesis occures from mixed progenitor cells through a series of nucleated red cell precursors (normoblast ) to a reticulocyte stage , containing RNA but not DNA.

-Various shorts or long-acting manifestations of erythropoietin are used clinically to treat anaemia in renal failure and other diseases.

-Haemoglobin is the main protien in red cells. It consists of four polypeptide (globin)chains, in adult 2 alpha and 2 beta,each conatining an iron atom bound to protoporphyrin to form haem.

-The red cell has two biochemical pathways for metabolizing glucose, the Embdn-Meyerhof which generate ATP and NADH and the hexose monophosphate pathway which generates NADPH, important for maintaining glutatione which keeps cell protiens in the membrane and haemoglobine the reduced state.

-The red cell membrane consists of a lipid bilayer with a membrane skeleton of penetrating and integral protiens and carbohydrate surface antigens.

- Anaemia is defines as a haemoglobin level in blood below the normal level for age and sex. Itis classified according to the size of the red cell into macrocytes. The reticulocytes count , morphology of the red cells and changes in the white cell and,or platelet count help in the diagnosis of the cause of anaemia.

-The general clinical features of anaemia include shortness of breath on exeration ,pallor of mucous membrane , tachycardia .

-Other feature relate to particular types of anaemia.e.g.jundice,leg ulcers.

-Bone marrow examination by aspiration or triphine biopsy may be important in the investigation of anaemia as well as of many other haematological diseases.

 

From book: Essentail Haematology A.V.HOFFBRAND,P.A.H.MOSS.6EDITION