IgM hyperimmunoglobulinemia syndrome

IgM hyperimmunoglobulinemia syndrome is a heterogeneous group of several types of antibody primary immunodeficiencies, of which type 1 is the best known and most common.

IgM hyperimmunoglobulinemia syndrome, type 1
This type (Hyper-IgM immunodeficiency X-linked, HIGM1, XHIM, OMIM: 308230 ) represents an X-linked immunodeficiency, caused by a mutation in the gene for the antigenic ligand CD40 (CD40LG, localization Xq26). This ligand is crucial for the interaction of T and B-lymphocytes before the initiation of the isotype switch from IgM production to other classes of immunoglobulins. Studies have shown that T-lymphocytes are defective, as B-lymphocytes of carriers (heterozygous women) are properly stimulated even with a small amount of non-defective T-lymphocytes.

Clinincal picture
Manifestation includes high levels of IgM and the absence of other immunoglobulin classes (IgG, IgA). In addition to the antibody deficiency, there is also a cellular deficiency - due to defective T-lymphocytes and autoimmune-induced neutropenia (tendency to develop autoimmune diseases). Manifestations include susceptibility to various bacterial and viral infections, including opportunistic infections (for example, diarrhea caused by Cryptosporidium parvum is typical).

Other types
Other types of IgM hyperimmunoglobulinemia syndrome are mentioned on a separate page.

Related Articles

 * Antibodies
 * Primary immunodeficiency
 * Burton's agammaglobulinemia

Source

 * ŠIPEK, Antonín. Genetically determined disorders of the immune system  [online]. Last revision 9/6/2006, [cit. 5/12/2009]. < http://www.genetika-biologie.cz/primarni-immunodeficiency >.