The precise symptoms of a<unk>  depend on the type of defect. Generally, the symptoms and signs that lead to the diagnosis of an immunodeficiency include recurrent or persistent infections or developmental delay as a result of infection. Particular organ problems (e.g. diseases involving the skin, heart, facial development and skeletal system) may be present in certain conditions. Others predispose to autoimmune disease, where the immune system attacks the body's own tissues, or tumours (sometimes specific forms of cancer, such as lymphoma). The nature of the infections, as well as the additional features, may provide clues as to the exact nature of the immune defect.
Primary immunodeficiency
Combined immunodeficiencies
Severe combined immunodeficiency
Selective immunoglobulin A deficiency
Common variable immunodeficiency
IgG deficiency
X-linked agammaglobulinemia
Adult-onset immunodeficiency syndrome