ASCIA‐P69: A NOVEL AICDA MUTATION IN A CASE OF AUTOSOMAL RECESSIVE HYPER‐IGM SYNDROME, GROWTH HORMONE DEFICIENCY AND AUTOIMMUNITY

Abstract

The Hyper-immunoglobulin M syndromes (HIGM) or immunoglobulin class switch recombination (Ig-CSR) deficiencies are rare primary immunodeficiency (PID) disorders. A 9-year-old girl with recurrent ear infections and failure to thrive since the age of 6 months had normal lymphocyte subsets, but extremely elevated IgM and significantly decreased IgG and IgA. In view of the patient's short stature, growth hormone evaluation was carried out and growth hormone deficiency established. The patient underwent Ig replacement therapy and received short course of growth hormone therapy and responded well. Furthermore, the patient developed benign cervical lymphadenopathy, as well as elevated ESR, positive autoantibodies to SSA-Ro, and severely dry eyes, which partially responded to both the punctate occlusion and systemic corticosteroids, at the age of 7 years. Sequencing analysis of the exons from activation-induced cytidine deaminase ( AICDA ) gene revealed that the patient was homozygous for a single T to C transversion at position 455 in exon 4, which replaces a Valine with an Alanine. To our knowledge, this is a new AICDA mutation, which has not been reported previously in HIGM. Autoimmune complications have been formerly described in the reported series of AICDA deficient HIGM; however the association with growth hormone deficiency is rarely reported.