CD40 Ligand Expression in Immunodeficiency with Hyper IgM and Congenital Rubella Syndrome

ABSTRACT

Immunodeficiency with hyper-IgM is characterized by increased susceptibility to infection, decreased concentrations of IgG and IgA and normal or elevated levels of IgM. It has been described in X-Iinked, autosomal recessive, autosomal dominant, and acquired forms. The acquired forms are usually due to insults such as malignancy and congenital rubella. The X-linked form is due to a mutation in the CD40 ligand (CD40L) gene located at Xq26–27, causing defective expression of CD40L. While CD40L expression has been found to be normal in several cases of non X-linked familial and sporadic forms, this has not been evaluated in cases of congenital rubella syndrome. We describe two female patients with immunodeficiency with hyper-IgM and clinical features suggestive of congenital rubella syndrome. In each patient, CD40L expression was normal. While in one patient with immunologic defect has persisted after 10 years, the other patient now has normal levels of IgG and IgM and undetectable IgA. To the best of our knowledge, long-term follow-up of this immunodeficiency disorder in congenital rubella syndrome has not previously been described.