A case of autoimmune enteropathy with CTLA4 haploinsufficiency
- Author:
Haruka MIYAZAKI
1
;
Namiko HOSHI
;
Michitaka KOHASHI
;
Eri TOKUNAGA
;
Yuna KU
;
Haruka TAKENAKA
;
Makoto OOI
;
Nobuyuki YAMAMOTO
;
Suguru UEMURA
;
Noriyuki NISHIMURA
;
Kazumoto IIJIMA
;
Keisuke JIMBO
;
Tsubasa OKANO
;
Akihiro HOSHINO
;
Kohsuke IMAI
;
Hirokazu KANEGANE
;
Ichiro KOBAYASHI
;
Yuzo KODAMA
Author Information
- Publication Type:Case Report
- From:Intestinal Research 2022;20(1):144-149
- CountryRepublic of Korea
- Language:English
- Abstract: Autoimmune enteropathy (AIE) is a rare disease, characterized by intractable diarrhea, villous atrophy of the small intestine, and the presence of circulating anti-enterocyte autoantibodies. Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome, and mutations in FOXP3, which is a master gene of regulatory T cells (Tregs), are major causes of AIE. Recent studies have demonstrated that mutations in other Treg-associated genes, such as CD25 and CTLA4, show an IPEX-like phenotype. We present the case of a 13-year-old girl with CTLA4 haploinsufficiency, suffering from recurrent immune thrombocytopenic purpura and intractable diarrhea. We detected an autoantibody to the AIE-related 75 kDa antigen (AIE-75), a hallmark of the IPEX syndrome, in her serum. She responded well to a medium dose of prednisolone and a controlled dose of 6-mercaptopurine (6-MP), even after the cessation of prednisolone administration. Serum levels of the soluble interleukin-2 receptor and immunoglobulin G (IgG) were useful in monitoring disease activity during 6-MP therapy. In conclusion, autoimmune-mediated mechanisms, similar to the IPEX syndrome, may be involved in the development of enteropathy in CTLA4 haploinsufficiency. Treatment with 6-MP and monitoring of disease activity using serum levels of soluble interleukin-2 receptor and IgG is suggested for such cases.
