The individual will typically not make antibodies against protein or polysaccharide antigens and will not make IgM antibodies against incompatible blood group antigens (hemagluttinins).
Immunoglobulin deficiencies refer to missing or reduced levels of immunoglobulin (IgG, IgA, IgM) associated with an inability to make adequate specific antibody.
Hepatitis A symptoms often go unrecognized because they are not specific to hepatitis A, thus a blood test (IgM anti-HAV) is required to diagnose HAV infection.
In these disorders, specific diseasefighting antibodies (immunoglobulins such as IgG, IgA, and IgM) are either missing or are present in reduced levels.
When the body is infected with the rubella virus, it produces both immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies to fight the infection.
A blood test can be used either to confirm a recent infection (IgG and IgM) or determine whether a person has immunity to rubella (IgG only).
A child with hyper-IgM syndrome will be found to have abnormally low levels of IgA and IgG antibodies and a normal or elevated level of IgM.
As a result, boys with XHIM have abnormally low levels of IgG and IgA in their blood, with normal or higher than normal levels of IgM.
This condition produces an increase in the amount of IgM antibodies present and a decrease in the amount of IgG and IgA antibodies.
Selective IgA deficiency is an inherited disease characterized by a failure of B cells to switch from making IgM to IgA antibodies.