Immune deficiencies or immunodeficiencies due to defects in various components of immune system are infrequent, though not insignificant ,and occur in two different ways
1- primary immunedeficiency are those caused by intrinsic or congenital defects .these deficiencies are genetic in nature ,but they may some times appear as the results of randomly occurring errors in development .over 100 diseases are known in human .
2- secondary immunedeficiencies are caused by enveromental causes such as infection ,therapeutic treatment ,cancer and malnutrition .these deficiency may occur at any time of life .
characteristics seen in many immune deficiencies diseases include the following
1- recurrent or chronic infection
2- inability to recovered the infections agents after standard antibiotic therapy
3- unusual infectious agents
primary immunedeficiency
defects causing primary ID may occur in different cell lineages
1- the combined lymphoid cell lineages T and B cell
2- Lineages producing phagocytic cells and natural killer cells
3- Cells producing complement components
A- defects in stem cells
The pluripotent stem that generate the granulocytic ,erythrocytic ,monocytic ,thrombocytic and lymphocytic lineages of t