低分子量尿蛋白在原发性肾小球肾炎中的作用

目的 探讨低分子量混合性尿蛋白在肾小球及小管间质损伤中的意义,评估尿蛋白分型的特征对诊断的价值。方法 采用薄层十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)对尿蛋白分型,将101例肾活检证实是原发性肾小球肾炎患者,分为70、150、23、10kd组,分别测定血清肌酐(Scr)、24h尿蛋白、尿视黄醇结合蛋白水平(RBP)及小管间质损害分数。结果 10kd组34.29％患者的Scr高于正常范围,且与其他三组相比有显著性差异(P<0.05)。四组患者24h尿蛋白均有不同程度的升高,其中23kd组和10kd组升高尤为显著,与另二组比较均有显著性差异(P<0.05)。在RBP及小管间质损害分数测定中,10kd组与其他三组比较均有显著性差异(P<0.05)。结论 当原发性肾小球肾炎患者出现分子量很低的23kd和10kd的混合性尿蛋白类型时,肾小球滤过功能和小管重吸收功能均受到损伤,后者可能预后更差。

The Clinical Significance of Urinary Low Molecular Weight Proteins in Primary Glomerulonephritis Patients

Objective To investigate the clinical implication of urinary mixed low - molecular weight protein (LMW) in the glomerular and tuhulointerstitial changes and the clinical diagnostic value in the patterns of proteinuria in primary glomerulonephritis, and to discuss the characteristics and prognostic significance of proteinuria. Methods In 101 patients with primary glomerulonephritis verified by renal biopsy , proteinuria was analyzed by thin - membrane sodium dodecyl sulphate - polyacrylamide gel electro-phoresis ( SDS - PAGE) , and classified into four patterns: 7()kd, 150kd, 23kd and 10kd. Meanwhile, the serum creatinine levels ( Scr) , 24h proteinuria, urinary retinol -binding protein (RBP) concentration and the scores of tubulointerstitial lesions were examined. Results Patients in the 10kd group had abnormal Scr value (34.29% ) (P <0. 05, compared with other three groups). The amounts of 24h proteinuria were increased and significantly high in the group of 23kd and 10kd groups compared with 70kd and 150kd groups (P < 0.0,5). Urinary RBP and the scores of tubulointerstitial lesions in the 10kd group were different from other three groups (P <0. 05). Conclusion Impairment in glomerular filtration function and tubular reabsorptive function were present in the patients with primary glomerulonephritis when proteinuria mixed with low molecular weight protein of 23kd and 10kd appeared. The patients with urinary protein of lOkd may have a poorer prognosis than those with other patterns of proteinuria. The appearance of 10kd , mixed proteins with lower molecular weight on thin membrane SDS - PAGE has prognostic value in primary glomerulonephritis.