Department of Nephrology, Children's Hospital of Nanjing Medical University, 72 Guangzhou Road, Nanjing, 210029, Jiangsu Province, China.
Pediatr Nephrol. 2025 Jan;40(1):89-93. doi: 10.1007/s00467-024-06482-7. Epub 2024 Aug 27.
A 3-year-old boy initially presented with purpura-like rashes and nephrotic syndrome, suspected to be IgA vasculitis nephritis (IgAVN). The suggestion of kidney biopsy was rejected. Although the patient responded well to glucocorticoids, they later developed recurrent proteinuria, refractory diarrhea, and subsequent metabolic acidosis. Kidney biopsy showed membranous nephropathy with positive semaphorin 3B expression, indicative of other kidney diseases rather than IgAVN. Although his kidney responded well to glucocorticoid combined with cyclosporine A treatment regimen, enteropathy and severe food allergy still progressed afterwards as evidenced by villous atrophy on gastrointestinal endoscopy examination. Whole exome sequencing identified a heterozygous missense variant in exon 11 of FOXP3: c.1121 T > G, confirming the diagnosis of immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome. The case expanded the phenotypic spectrum of IPEX syndrome, suggesting high phenotypic heterogeneity despite similar genotypes. It also put emphasis on the significance of kidney biopsy to differentiate IgA vasculitis nephropathy from other immune disorders.
一名 3 岁男童最初表现为紫癜样皮疹和肾病综合征，疑似 IgA 血管炎肾炎（IgAVN）。但肾脏活检的建议被拒绝了。尽管患者对糖皮质激素反应良好，但后来出现复发性蛋白尿、难治性腹泻，随后发生代谢性酸中毒。肾脏活检显示膜性肾病，Semaphorin 3B 呈阳性表达，提示为其他肾脏疾病而非 IgAVN。尽管他的肾脏对糖皮质激素联合环孢素 A 治疗方案反应良好，但随后肠病和严重食物过敏仍在进展，胃肠道内镜检查显示绒毛萎缩。全外显子组测序在 FOXP3 exon 11 中发现了一个杂合错义变异：c.1121T>G，明确了免疫失调、多内分泌腺病、肠病、X 连锁（IPEX）综合征的诊断。该病例扩展了 IPEX 综合征的表型谱，表明尽管基因型相似，但表型高度异质性。该病例还强调了肾脏活检在鉴别 IgA 血管炎肾炎与其他免疫紊乱方面的重要性。
