Prenatal Diagnosis of X-Linked Hyper-IgM Syndrome

The inability to initiate switching from one immunoglobulin isotype to another is the hallmark of the hyper-IgM immunodeficiency syndrome1. Patients with this primary immune disorder, originally termed “dysgammaglobulinemia type 1,”2 usually present with recurrent bacterial infections, including otitis media and pneumonia. Additional clinical features include opportunistic infections, recurrent neutropenia, lymphoid hyperplasia, and autoimmune manifestations. Abnormalities of serum immunoglobulins include low levels or an absence of IgG, IgA, and IgE and normal or, more frequently, elevated levels of IgM and IgD. The hyper-IgM syndrome can be inherited in an X-linked or autosomal recessive fashion. The candidate gene for this disease . . .