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Types of PI

There are more than 450 primary immunodeficiencies. Explore the definitions and symptoms of some of the most common types.


Schimke’s immuno-osseous dysplasia

Schimke’s immuno-osseous dysplasia, an autosomal recessive disorder, is caused by a variant in a gene responsible for chromatin remodeling (SMARCAL1).

Selective IgA deficiency

Selective IgA deficiency is a primary immunodeficiency characterized by an undetectable level of immunoglobulin A (IgA) in the blood and secretions but no other immunoglobulin deficiencies.

Selective IgM deficiency

Individuals with selective IgM deficiency have low levels or lack immunoglobulin M (IgM) but have normal levels of IgA, and IgG. These individuals may have no illness, whereas others develop a variety of illnesses, including infections, allergies, and autoimmunity. 

Severe combined immunodeficiency (SCID)

Severe combined immune deficiency (SCID) is a life-threatening primary immunodeficiency (PI), with a combined absence of T cell and B cell function. There are at least 20 different genetic variants that can cause SCID.

Specific antibody deficiency

Individuals with specific antibody deficiency have normal levels of antibodies (immunoglobulins) but cannot produce antibodies to specific types of microorganisms that cause respiratory infections.

STAT1 and STAT3 gain of function

STAT1 and STAT3 gain of function are autosomal dominant primary immunodeficiencies with significant autoimmunity as a result of immune dysregulation.

STK4 deficiency

The clinical phenotype for STK4 deficiency includes persistent viral infections and bacterial infections. Other reported features include fungal infections, mild eczema, autoimmune cytopenias, and lymphopenia.