ABSTRACT
Similarly, the natural microflora of many of these surfaces provides powerful competitive exclusion to pathogens and may also be considered an innate protective feature.
The immune system interfaces with virtually all other body systems and consequently almost all diseases have an immunologic aspect. For example, the immune system will respond appropriately to the presence of infectious or neoplastic disease, or the existence of a chronic disease state may lead to secondary immunosuppression. More importantly, there is a wide range of diseases that have an immunopathological basis and these are the focus of this chapter. In order to fully understand these primary immunologic disorders, a solid working knowledge of the immune system is required. This chapter will briefly overview current knowledge of the immune response and immunopathology, and then discuss the four major categories of immune-mediated disease: (1) allergic disease; (2) autoimmune disease; (3) primary immunodeficiency disease; and (4) immune system neoplasia. Many of the key diseases within these groups are discussed in the individual systems-based chapters of this book. These will be cross-referenced from this chapter, and only selected immunologic disorders not covered elsewhere will be presented here.
