immune disorders
Hyper IgM Syndrome
Introduction
Hyper-IgM syndrome is characterized by normal or high levels of immunoglobulin M (IgM) and decreased levels or absence of other immunoglobulins. As a result, people are more susceptible to bacterial infections. Children with hyper-IgM syndrome have frequent sinus and lung infections. Doctors diagnose the disorder by measuring levels of immunoglobulins in the blood and by doing genetic tests. Treatment involves immune globulin, antibiotics to prevent infections, and, when possible, stem cell transplantation. (See also Overview of Immunodeficiency Disorders .) IgM is one of 5 types of Antibodies , which help defend the body against infection. The level of IgM is elevated or sometimes normal in hyper-IgM syndrome, but this is not the cause of the immunodeficiency. Other Hyper-IgM syndrome is a Primary immunodeficiency . It may be inherited in one of the following ways: As an X-Linked Inheritance : That is, it is due to a mutation in a gene on the X (sex) chromosome. X-linked disorders usually affect only boys. As an Inheritance Patterns : That is, two genes for the disorder, one from each parent, are required. Most cases of hyper-IgM syndrome are X-linked. How the disorder affects people varies depending on which gene is affected. 