systemic vasculitis and high ige level in a patient with lps-responsive beige-like anchor (lrba) deficiency

Background: mutations in lps-responsive and beige-like anchor (lrba) gene in patients were firstly described to associate with a syndrome of immune deficiency and autoimmunity in 2012. however, there was still no lrba deficient patient reported in china. objectives: we present a chinese patient with heterozygous lrba gene mutations with his clinical, immunological and genetic features. methods: patient’s clinical data was collected and analyzed. laboratory results included lymphocyte subsets analysis and immunoglobulin quantification. targeted gene capture followed by next-generation sequencing was used to identify the gene mutations, and flow cytometry assay was used to analyze b cell immunophenotyping of this patient. results: the patient mainly suffered from recurrent respiratory tract infections, ebv-associated lymphoproliferative disease and systemic vasculitis. heterozygous lrba gene mutations were identified in the patient, which were inherited from his parents, respectively. b cell immunophenotyping revealed that he had decreased total b cells, bone marrow progenitor b cell subsets (hsc, clp, pro-b and pre-b cells), immature b cells, non-switched memory b cells, switched memory b cells and b1 cell subsets. besides, he had extremely high level of ige. conclusions: herein, we firstly report a patient with heterozygous lrba gene mutations in china. lrba might play an important role in b cell development.