Novel RAG2 Mutation in a Patient with Leaky Severe Combined Immunodeficiency

Salar Pashangzadeh; Reza Yazdani; Samaneh Delavari; Hassan Abolhassani; Nima Parvaneh

doi:10.18502/igj.v4i4.12758

Salar Pashangzadeh Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
Reza Yazdani Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
Samaneh Delavari Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
Hassan Abolhassani Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran
Nima Parvaneh Division of Allergy and Clinical Immunology, Department of Pediatrics, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran

DOI: https://doi.org/10.18502/igj.v4i4.12758

Keywords: RAG2; Combined Immunodeficiency; Severe Combined Immunodeficiency; Primary Immunodeficiency; IgA Deficiency

Abstract

T and B lymphocytes development and function are highly dependent on Recombination Activating Genes (RAG) 1 and 2. RAG mutations result in different degree of T and B cell impaired function, broad clinical manifestations, and immunological manifestations. Pathogenic mutations cause severe combined immunodeficiency (SCID) phenotype, while hypomorphic mutations are responsible for leaky or partial SCID.

Here, we described a 4-year-old girl who had a persistent diarrhea, recurrent infection and vomiting. Although physicians were suspicious about autoimmune enteropathy, her molecular report showed a homozygous and novel RAG2 mutation in its core domain. The number of CD4 T cells and IgA level were lower than normal ranges. Lack of IgA brought about different GI complications. Our patient died finally because of the liver and gallbladder failure.