激素耐药性肾病伴泌尿生殖器异常患儿的临床特点及形WT1基因分析  

Clinical characteristics and WT1 genetic analysis of patients with steroid.resistant nephrotic syndrome accompanied with genitourinary malformations

作　　者：李建国[1] 赵丹[1] 丁洁[1] 肖慧捷[1] 范青锋[1] 管娜[1] 陈彦[1] 张宏文[1] 

机构地区：[1]北京大学第一医院儿科,100034

出　　处：《中华儿科杂志》2008年第9期692-697,共6页Chinese Journal of Pediatrics

基　　金：国家自然科学基金资助项目（30170992,30672259）;北京市自然科学基金资助项目（7072080）;“十一五”国家科技支撑计划（2006BA105A07）志谢 衷心感谢Karl Tryggvason教授（瑞典）和Corinne Antignac教授（法国）馈赠抗体,感谢北京大学第一医院小儿肾脏组的邢燕同学及俞礼霞、武国红、姚勇、黄建萍、刘景城、杨霁云老师的支持

摘　　要：目的分析激素耐药性肾病伴泌尿生殖器异常患儿的临床特点、WT1基因及足细胞分子表达，提高对WT1基因突变在该类疾病的重要致病作用的认识。方法收集3例激素耐药性肾病伴有或怀疑有泌尿生殖器异常的患儿。采用PCR及RT—PCR的方法分析WT1基因及＋KTS（赖氨酸-苏氨酸-丝氨酸）／-KTS比例；采用间接免疫荧光及免疫组化的方法进行足细胞分子（nephrin，podocin，α-acfinin4，WT1及CD2AP）表达。结果3例患儿发病年龄分别为6个月、1岁及10岁；2例为男性伴泌尿外生殖器异常，1例为男性假两性畸形；临床均表现激素耐药肾病，2例肾脏病理为局灶节段性肾小球硬化。2例检测到WT1突变，即WT1 IVS9＋5G〉A和WT1外显子91186G〉A杂合突变。足细胞分子在WT1突变肾组织表达发生改变；1例无WT1表达，1例WT1在足细胞细胞核内的分布与正常对照不同。结论对于激素耐药性肾病的女性患者或伴有泌尿生殖器异常的男性患者应行染色体核型和WT1基因分析。WT1突变除可能引起＋KTS／-KTS比例异常，还伴有足细胞分子表达异常，从而导致蛋白尿的形成和（或）发展。Objective To analyze the clinical features and WT1 gene mutations in patients with steroid-resistant nephrotic syndrome （SRNS） accompanied with genitourinary malformations. The expression of podocyte molecules was also investigated in renal specimen of these WT1 mutated patients. Methods From January 2005 to May 2007, 3 cases of SRNS accompanied with genitourinary malformations were involved in this study. The expression of podocyte molecules （ nephrin, padocin, α-actinin 4, WT1 and CD2AP） in 2 cases was analyzed by immunofluorescence and immunohistochemistry; using PCR to amplify genomic DNA and RT-PCR to amplify WT1 cDNA. GeneScan and GeneScan software were used to quantify the ratio of ＋ KTS/- KTS isoforms. Results The age of onset of the 3 cases were 6 months, 1 year and 10 years, respectively. The age at diagnosis was 7 months, 9 years and 15 years, respectively. The phenotype of case 1 and case 3 was male accompanied with genitourinary malformations. Case 2 was phenotypic female. Karyotype analysis of the 3 cases revealed 46, XY. Each case was diagnosed as SRNS. Focal segmental glomerulosclerosis （FSGS） was confirmed in 2 cases. Podocyte molecular expression altered in renal tissues of 2 cases. WT1 staining was negative in case 1. WT1 expression in case 2 showed a diffuse nuclear staining with less obvious speckles compared with controls. WT1 IVS 9 ＋ 5 G 〉 A mutation was detected in case 2 and WT1 exon 9 1186 G 〉A mutation was detected in case 3. No WT1 mutation was detected in case 1. Conclusions Karyotype analysis and WT1 genetic analyzing should be performed for all female patients with early onset SRNS and in male patients with SRNS accompanied with genitourinary malformations. The abnormal ratio of ＋ KTS/- KTS isoforms caused by WT1 mutations along with abnormal expression of padocyte molecules were involved in the pathogenesis of proteinuria.

关 键 词：肾病综合征 激素耐药 泌尿生殖器异常 WT1 足细胞 

分 类 号：R686[医药卫生—骨科学]