ABSTRACT
Primary immunodeficiencies can be classified by a variety of criteria, such as the main limb of the immune system affected, the spectrum of infections, their primary or secondary nature, and, in the case of hereditary primary immunodeficiencies, their mechanism of genetic transmission (Table 1). Most of the known primary immunodeficiency diseases, as classified by the International Union of Immunological Societies, are listed in Table 2. This chapter reviews some of the more common and well-characterized primary immune disorders, in order to discuss their clinical relevance and to review their mechanism of disease. Many of these disorders have provided great insight into the function of the normal human immune response.
