A hemizygous mutation in the FOXP3 gene (IPEX syndrome) resulting in recurrent X-linked fetal hydrops: a case report

Panicos Shangaris,Joo Wook Ahn,Jacqueline Hoyle,Melita Irving,Muriel Holder-Espinasse,Sian Ellard,Diana Wellesley,Andreas Marnerides,Simi George,Dharmintra Pasupathy,Alison Ho,Mattias Jansson,Mudher Aladnani,Shu Yau

doi:10.1186/s12920-021-00901-6

Abstract

BackgroundFetal hydrops is excessive extravasation of fluid into the third space in a fetus, which could be due to a wide differential of underlying pathology. IPEX (immune dysregulation, polyendocrinopathy, enteropathy, X-linked) syndrome primarily affects males. It is a monogenic primary immunodeficiency syndrome of X-linked recessive inheritance due to FOXP3 gene variants. It is characterised by the development of multiple autoimmune disorders in affected individuals.Case presentationWe present a rare cause of male fetal hydrops in the context of IPEX syndrome and discuss FOXP3 gene variants as a differential for ‘unexplained’ fetal hydrops that may present after the first trimester.Discussion and conclusionsIn all similar cases, the pathological process begins during intrauterine life. Furthermore, there are no survivors described. Consequently, this variant should be considered as a severe one, associated with intrauterine life onset and fatal course, i.e., the most severe IPEX phenotype.

Highlights

Fetal hydrops is excessive extravasation of fluid into the third space in a fetus, which could be due to a wide differential of underlying pathology
Further‐ more, there are no survivors described. This variant should be considered as a severe one, associated with intrauterine life onset and fatal course, i.e., the most severe immune dysregulation-polyendocrinopathy-enteropathy x-linked (IPEX) phenotype
The immune dysregulation-polyendocrinopathy-enteropathy x-linked (IPEX) syndrome is a primary immunodeficiency caused by variants in the Forkhead box P3 (FOXP3) gene [1, 2]

Summary

Discussion and conclusions

In the context of male fetal hydrops, variants in the FOXP3 gene and resultant IPEX syndrome may be a cause for ‘unexplained’ cases following routine investigations. This report reinforces that IPEX should be considered as an underlying disease in recurrent male miscarriages as well as in unexplained fetal hydrops. This variant should be considered as a severe one, associated with intrauterine life onset and fatal course, i.e., the most severe IPEX phenotype. This is in contrast to other causes of fetal hydrops (such as chromosomal abnormality [13]) and may be due to compromised ability to develop self-tolerance, as the fetus is significantly challenged by its endogenous immune system in the second trimester.

Background