Primary immunodeficiency

In general, immunodeficiencies are divided into those of the specific immune system (e.g. T cells or B cells or combined) or those of the innate or non-specific immune system (e.g. complement and neutrophils). Immunodeficiencies may also be divided into primary (usually genetic) and secondary, where the immune defect is caused by some other non-immunological disease. This chapter describes the classification and clinical features of primary immunodeficiencies, and then the cause, presentation, diagnosis, immunology, and treatment for a wide range of immunodeficiencies.