Two Female Siblings with Childhood-Onset Systemic Lupus Erythematosus

We herein report two female siblings with childhood-onset Systemic Lupus Erythematosus (SLE) who developed membranous lupus nephritis. The children were diagnosed as having SLE in reverse birth order at ages 11 and 14 years. Younger sister's initial symptom was edema and laboratory findings indicated proteinuria, hypocomplementemia and positive ANA/anti-dsDNA antibody. She was diagnosed as being SLE with membranous lupus nephritis based on International Society of Nephrology/Renal Pathology Society (ISN/RPS) 2003 classification. Elder sister manifested general fatigue and edema twelve months after her sister. Laboratory findings showed proteinuria, hypocomplementemia, and positive ANA/anti-dsDNA antibody. A renal biopsy revealed mixed form of mesangial proliferative glomerulonephritis and membranous nephritis. Moreover, both of them were complicated with secondary Sjögren's syndrome. HLA typing was performed and the siblings were noted to have the same haplotype; A(*)0207, A(*)2402, B(*)4601, B(*)5201, B(*)5201, Cw(*)0102, Cw(*)1202, DRB1(*)0101, DRB1(*)0803.