Abstract: Objective To analyze the clinical and genetic characteristics of immune dysregulation polyendocrinopathy enteropathy X-linked (IPEX) syndrome. Methods The clinical data and genetic test results of 1 patient with IPEX syndrome were analyzed, and related literatures were reviewed. Results The boy developed immune thrombocytopenia at 14 months of age. He had recurrent respiratory tract infection with secondary immune thrombocytopenia and hepatitis, accompanied by splenomegaly and lymphadenopathy. Genetic test found that the child had a hemizygotic variation in FOXP 3 gene, and nucleotide 767 changed from thymine T to cytosine C (c. 767 T >C), resulting in amino acid 256 changed from methionine to threonine (p.M 256 T). Pedigree verification showed that there was no variation at this locus in the father and a heterozygous variation at this locus was found in the mother. After one month of rapamycin treatment, the platelet level rose significantly and the liver function returned to normal. However, the patient died 3 months later due to severe infection. Conclusions IPEX syndrome is a multi-organ autoimmune disease with high mortality. Immunosuppressive therapy followed by allogeneic hematopoietic stem cell transplantation is the current optimal treatment.

Key words: immune dysregulation polyendocrinopathy enteropathy X-linked syndrome; FOXP3 gene; immune thrombocytopenia; hepatitis