Primary Immunodeficiency (PI) is an umbrella term for more then 100 genetic defects that range widely in severity.

PI affects males and females of all ages, but the most severe forms are detected most frequently in childhood.

Symptoms of a PI disease are often overlooked because they appear to be common childhood illnesses such as sinus and ear infections, pneumonia, fever, and bronchitis. Thus, families and doctors are often unaware that the troubling conditions they are dealing with are actually rooted in a defect in the immune system and treat the symptoms rather than addressing the underlying cause.

Failure to diagnose PI can lead to a life of serious chronic illness, permanent damage, or even premature death.

The majority of PI patients are diagnosed with one of the following specific conditions.
You can access more detailed information by clicking on the links below:

Selective IgA Deficiency
This is the most common of the primary Immunodeficiencies. It is defined as the total absence or severe deficiency of IgA. Blood serum levels for IgA deficient persons are usually found to be 7 mg/dl or less, while serum IgA in normal adults ranges from 90 to 450 mg/dl.
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DiGeorge Syndrome
This is also called thymic aplasia (failure of the thymus to develop naturally), thymic hypoplasia (defective development of tissue), or third and fourth pharyngeal arch or pouch syndrome. This is a congenital immune disorder characterized by lack of embryonic development (stage in prenatal development between 2-8 weeks inclusive) or underdevelopment of these pharyngeal pouches. The syndrome is often associated with congenital heart defects, abnormalities of the large blood vessels around the heart, failure of the esophageal tube to develop, abnormalities of facial structures, and of hypoparathyroidism (insufficient secretion of the parathyroid glands). In most cases, there is a chromosomal defect on chromosome 22.
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Common Variable Immunodeficiency
This is characterized by a lack of antibody producing B-cells or plasma cells, low levels of most or all immunoglobulin classes, and recurrent bacterial infections. Its name is derived from the fact that it is a relatively common form of immune disorder and that the degree and type of deficiency, as well as its clinical signs and symptoms, vary among patients.
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X-Linked Agammaglobulinemia [Brutons Disease]
This was the first immunodeficiency to be identified. It is sometimes called Bruton Type Agammaglobulinemia, X-Linked Infantile Agammaglobulinemia, or Congenital Agammaglobulinemia. It is an inherited disorder localized to the central region of the long arm of the X chromosome and is thus found in males. However, this X-linked pattern of transmission cannot be demonstrated in all families, possibly because of small family size, and because in a certain percentage of cases, a new mutation in the gene locus on the X chromosome has occurred. The gene locus is a specific enzyme (BtK) which prompts B-cells to become mature and able to produce antibodies.
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Severe Combined Immunodeficiency [SCID]
This represents a severe defect in T- and B- lymphocyte development resulting in marked susceptibility to severe and complicated infections. (White blood cells are necessary for normal immunity.) The onset of infection usually occurs in the first six months of life. Severe Combined Immunodeficiency is considered to be the most serious of the primary immune disorders.
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Chronic Granulomatous Disease
This is an inherited disorder characterized by a defect in which neutrophils (white blood cells in the body that kill invading bacteria or fungus) are unable to kill certain microorganisms.
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IgG Subclass Deficiency
This occurs when there is an imbalance of the IgG subclasses with one or more subclasses being deficient. The overall level of IgG can be normal, but individual subclass levels may be higher or lower than normal.
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