First reported case of Omenn syndrome in a patient with reticular dysgenesis

摘要

To the Editor:Reticular dysgenesis (RD) is a rare form of autosomal-recessive severe combined immunodeficiency characterized by lack of circulating T lymphocytes, severe congenital neutropenia, and sensorineural deafness.The disease is caused by mutations in the gene encoding adenylate kinase 2 (AK2), a mitochondrial protein important for regulating intracellular levels of adenosine diphosphate and maintaining mitochondrial membrane potential. A similar function is also mediated by the cytoplasmic enzyme AK1. While most tissues express both AK1 and AK2 enzymes, neutrophils, T lymphocytes, and cells of the stria vascularis in the inner ear uniquely express AK2, thus explaining the RD phe-notype.Omenn syndrome (OS) has been described in association with several genetic defects responsible for severe combined immunodeficiency and results from residual development of oli-goclonal T lymphocytes that undergo peripheral expansion and infiltrate various tissues including the skin, gut, liver, and lym-phoid organs. We report the first case of OS in a patient with RD.