Crosson J T
Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, Minnesota 55415, USA.
Transplant Proc. 2007 Apr;39(3):737-43. doi: 10.1016/j.transproceed.2007.02.010.
Primary focal segmental glomerulosclerosis (FSGS) is a major cause of nephrotic syndrome and eventual end-stage renal disease. It is known to be due to an abnormality of the visceral epithelial cells (podocytes) of the glomerulus. The morphological hallmark of primary FSGS is diffuse effacement of podocyte foot processes. The etiology of the podocyte damage is not been clearly established. FSGS can also be a secondary process due to underlying conditions including obesity and heroin use. In the secondary processes, the mechanism appears to be a decreased ratio of podocytes to the glomerular filtration surface area. Familial forms of FSGS also exist due to alterations of several different podocyte proteins. Primary FSGS is an increasing cause of end-stage renal disease. Recurrence of severe FSGS in renal allograft recipients presents a major challenge to transplant physicians. The incidence of recurrence is generally accepted to be between 20% and 30%. Risk factors for and characteristics of recurrence include a rapid progression of the primary disease to end-stage renal failure, early onset of nephrotic range proteinuria after allografting, frequent loss of the allograft, a high frequency of recurrence in subsequent allografts, and children less than 15 years of age. Some investigators have identified a circulating factor called the FSGS factor that appears to be associated with recurrence after transplantation. This factor has been shown to be a protein between 30 and 50 kd molecular weight. Logically, the possibility of a circulating factor associated with recurrence of FSGS led investigators to treat patients with plasmapheresis. Several studies have been reported with varying success. The response of patients to plasmapheresis seems to be completely individual. Other studies have added cyclophosphamide and/or mycophenolate mofetil to the plasmapheresis protocol. Again success in these studies has been variable. However, because some patients show complete recovery with plasmapheresis, individuals who develop recurrent FSGS after transplantation usually are given a trial of plasmapheresis therapy.
原发性局灶节段性肾小球硬化（FSGS）是肾病综合征及最终终末期肾病的主要病因。已知其病因是肾小球脏层上皮细胞（足细胞）异常。原发性FSGS的形态学特征是足细胞足突弥漫性消失。足细胞损伤的病因尚未明确。FSGS也可能是继发于肥胖和使用海洛因等潜在疾病的过程。在继发性过程中，其机制似乎是足细胞与肾小球滤过表面积的比例降低。由于几种不同的足细胞蛋白发生改变，也存在家族性FSGS。原发性FSGS是终末期肾病日益常见的病因。肾移植受者中严重FSGS的复发给移植医生带来了重大挑战。复发率普遍认为在20%至30%之间。复发的危险因素和特征包括原发性疾病迅速进展至终末期肾衰竭、移植后早期出现肾病范围蛋白尿、移植肾频繁丢失、后续移植肾复发频率高以及年龄小于15岁的儿童。一些研究人员发现了一种称为FSGS因子的循环因子，似乎与移植后复发有关。该因子已被证明是一种分子量在30至50kd之间的蛋白质。从逻辑上讲，存在与FSGS复发相关的循环因子这一可能性促使研究人员对患者进行血浆置换治疗。已有多项研究报告，结果各异。患者对血浆置换的反应似乎完全因人而异。其他研究在血浆置换方案中加入了环磷酰胺和/或霉酚酸酯。同样，这些研究的成功率也各不相同。然而，由于一些患者通过血浆置换完全康复，移植后发生复发性FSGS的个体通常会接受血浆置换治疗的试验。
