A case of novel NFKB2 mutation with hypertensive emergency and nephrotic syndrome leading to CKD G5D

Abstract [Background] Nuclear factor kappa B (NF-κB) family plays a central role in human immune system regulation. Heterozygous mutations in NFKB2 typically cause immunodeficiency with various degrees of central adrenal insufficiency, autoimmunity and ectodermal dysplasia. No reported case has presented kidney failure as an initial symptom. Moreover, documentation of kidney involvement of this disease is limited. [Case-Diagnosis] A patient with a novel heterozygous mutation in NFKB2 (c.880del: p. Tyr294Ilefs*4) developed dyspnea and hypertensive emergency as a result of kidney failure. She showed mild hypogammaglobulinemia, but no adrenal insufficiency or ectodermal dysplasia. She is now dependent on peritoneal dialysis and is awaiting kidney transplantation. [Conclusions] Clinical phenotype and penetrance of NFKB2 mutation might vary depending on the mutation site and its effects on NFKB2-signaling pathway. Whether kidney failure is a primary symptom of this variant or secondary to some event remains unknown. Further case accumulation is warranted. (145 words) [Summary - What is new] This is the first reported case of NFKB2 mutation with kidney failure presented as an initial symptom, leading to chronic kidney disease (CKD) G5D.