检测肾病综合征患者尿中足细胞的临床意义

目的:探讨尿中肾小球上皮细胞(足细胞)检测在人局灶节段性肾小球硬化症(focal segmental glomerulosclerosis,FSGS)诊断中的意义.方法:病例选自我科经肾活检病理证实的FSGS患者12例,微小病变性肾小球病(minimal change disease,MCD)20例,8例健康人作对照.取晨尿离心,沉渣甩片,间接免疫荧光法检测尿中足细胞特异蛋白Podocalyxin(PCX)阳性染色细胞.采用免疫荧光法检测肾小球足细胞PCX的表达.结果:FSGS组尿中足细胞阳性8例(阳性率66.67%),MCD组和正常对照组中尿足细胞均为阴性.FSGS患者中,尿足细胞阳性者临床上呈肾病综合征表现.FSGS患者肾活检标本中,肾小球内均可见足细胞特异标记蛋白PCX表达呈节段性缺失,并与肾小球节段硬化部位一致;而MCD患者肾活检标本的肾小球中,上述标记蛋白表达完整.结论:在肾病综合征中,尿足细胞检测可作为FSGS与MCD鉴别的一项可靠、方便、无创性的辅助手段.

The clinic significance of urinary podocytes in patients with focal segmental glomerulosclerosis

Objective: To address the significance of urinary podocytes in the diagnosis of human focal segmental glomerulosclerosis(FSGS). Methods: Twelve patients with FSGS and 20 patients with minimal change disease (MCD) were diagnosed by routine renal biopsy, and 8 healthy persons as controls. Morning urinary sediments was collected and centrifuged onto glass slides. Urinary podocytes were identified by immunofluorescent staining of podocyte specific protein Podocalyxin(PCX). The state of podocytes in glomeruli was observed using immunofluorescence. Results: Urinary podocytes were found in 8 out of 12 FSGS patients(66.67%), whereas none of 20 patients with MCD and control had podocytes in their urine. FSGS patients with positives urinary podocytes had prominent manifestation of nephropathy syndrome, whereas no nephrotic syndrome in patients with negative urinary podocytes. Focal absence of the expression of PCX, a marker protein of podocytes in glomeruli was found in FSGS patients, and the locations of absence were consistent with the lesions of focal sclerosis in glomeruli. In contrast, PCX was expressed integrally in MCD patients. Conclusion: Appearances of podocytes in urine of patients with nephropathy may be used as one of the reliable, convenient and unharmful accessorial methods for distinguished diagnosis of FSGS and MCD.