Sirolimus alleviated intractable diarrhea of IPEX syndrome: a case report and literature review

Background Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a rare single-gene X-linked immunodeficiency disease caused by mutations in the forkhead box protein 3 (FOXP3) gene. The typical clinical manifestations of IPEX mainly include severe atopic dermatitis, insulin-dependent type 1 diabetes mellitus, and intractable diarrhea. Case presentation Here, we report a boy with intractable diarrhea diagnosed with early-onset IPEX syndrome due to the c.434C > T (p.Ala145Val) mutation in exon 4 of the FOXP3 gene. The patient experienced intractable diarrhea and severe weight loss, and his clinical symptoms could not be alleviated by conventional supportive and anti-infection treatment. Sirolimus, an immunosuppressant, preferentially inhibits effector T cells while allowing the proliferation of Tregs and is used to treat IPEX patients and alleviate intractable diarrhea. Conclusion We reviewed the literature on the use of sirolimus for the treatment of IPEX syndrome over the past two decades.