Book contents
- Frontmatter
- Contents
- List of Contributors
- 1 Basic Components of the Immune System
- 2 Immunological Techniques
- 3 Immune Regulation
- 4 Immunological Aspects of Infection
- 5 Immunological Aspects of Immunodeficiency Diseases
- 6 Autoimmunity
- 7 Chronic Lymphocytic Leukemia
- 8 Immunology of HIV Infections
- 9 Immunological Aspects of Allergy and Anaphylaxis
- 10 Immunological Aspects of Skin Diseases
- 11 Experimental Approaches to the Study of Autoimmune Rheumatic Diseases
- 12 Immunological Aspects of Cardiac Disease
- 13 Immunological Aspects of Chest Diseases: The Case of Tuberculosis
- 14 Immunological Aspects of Gastrointestinal and Liver Disease
- 15 Immunological Aspects of Endocrine Disease
- 16 Immune-Mediated Neurological Syndromes
- 17 Immunological Aspects of Renal Disease
- 18 Immunological Aspects of Transplantation
- Index
5 - Immunological Aspects of Immunodeficiency Diseases
Published online by Cambridge University Press: 18 December 2009
- Frontmatter
- Contents
- List of Contributors
- 1 Basic Components of the Immune System
- 2 Immunological Techniques
- 3 Immune Regulation
- 4 Immunological Aspects of Infection
- 5 Immunological Aspects of Immunodeficiency Diseases
- 6 Autoimmunity
- 7 Chronic Lymphocytic Leukemia
- 8 Immunology of HIV Infections
- 9 Immunological Aspects of Allergy and Anaphylaxis
- 10 Immunological Aspects of Skin Diseases
- 11 Experimental Approaches to the Study of Autoimmune Rheumatic Diseases
- 12 Immunological Aspects of Cardiac Disease
- 13 Immunological Aspects of Chest Diseases: The Case of Tuberculosis
- 14 Immunological Aspects of Gastrointestinal and Liver Disease
- 15 Immunological Aspects of Endocrine Disease
- 16 Immune-Mediated Neurological Syndromes
- 17 Immunological Aspects of Renal Disease
- 18 Immunological Aspects of Transplantation
- Index
Summary
INTRODUCTION
The principal function of the immune system is to prevent microbial infection. Therefore, disorders resulting in impaired function of the immune system (immunodeficiency) result in increased susceptibility to infection. Immunodeficiency can arise from an intrinsic defect of a component of the immune system (primary immunodeficiency, or PID). Alternatively, immunodeficiency may be secondary to another pathological condition, which adversely affects immune function (Table 5.1). Both primary and secondary immunodeficiencies result in increased susceptibility to infection. The precise pattern of infection depends on the specific component of the immune system that is affected. Most PIDs are caused by defects in single genes and are hence heritable. Others may represent the consequence of an interaction between the genetic phenotype and an environmental influence, like viral infections. Primary immunodeficiencies are rare and based on information from national registers; these diseases are estimated to occur between 1 in 2,000 to 1 in 10,000 live births. In contrast, secondary immunodeficiencies are more commonly seen in clinical practice. (See Table 5.1 for examples of secondary immunodeficiency.)
From a clinical perspective, immunodeficiencies can be classified into eight categories (Table 5.2). Each category has a characteristic pattern of clinical presentation (Table 5.3), which will be elaborated on later.
DEFECTS IN ANATOMICAL OR PHYSIOLOGICAL BARRIERS TO INFECTION
One of the commonest predisposing causes of infection is a defect in an anatomical or physiological barrier to infection. Intact epithelial membranes, especially stratified squamous epithelial surfaces such as the skin, constitute an extremely effective barrier to infection. Thus, integumentary damage caused by burns, eczema, and trauma (including surgery), predisposes to infection.
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- Information
- Essential Clinical Immunology , pp. 61 - 90Publisher: Cambridge University PressPrint publication year: 2009