Selective Proteinuria Index as a Prognostic Index in IgA Nephropathy / 대한신장학회잡지

ABSTRACT

PURPOSE: Proteinuria is the hallmark of glomerular injury and results from alterations in glomerular permeability. The permeability of diseased glomerulus has been estimated by selectivity of proteinuria. Recently, some authors showed a significant relationship between selectivity of proteinuria and tubulointerstial damage. The present study examines the role of protein selectivity as a prognostic marker in patients with IgA nephropathy and its correlation with other prognostic indices. METHODS: The selective proteiuria index of 81 cases with IgA nephropathy diagnosed between 1990 and 2000 were reviewed, and each case was subclassified using the following highly selective(SPI0.2). The mean age of the patients was 27+/-15 years with a follow-up period of 38+/-24 months. Six patients had highly selective proteinuria, thirty three patients had moderately selective proteinuria, and forty two patients had nonselective proteinuria. RESULTS: 1) A significant relationship was found between the SPI and Haas subclasess(p=0.01). With respect to clinical presentaion, hypertension(0, 4, 11 cases, p<0.05), proteinuria(0.52+/-0.35, 1.85+/-1.55, 2.79+/-2.51 g/day, p<0.05) were significant correlation.2) Chronic renal failure was significantly higher in patients with nonselective proteinuria in comparison with patients with selective proteinuria(p<0.05).3) Markers of renal failure by the Cox proportional hazards model were Cr(Exp(B)=4.2, p<0.001), Ccr (Exp(B)=2.1, p<0.05), SPI(Exp(B)=1.7, p<0.05), hypertension(Exp(B)=1.6, p<0.05). 4) In 28 patients of IgA nephropathy with nephrotic syndrome, 9 patients were moderately selective, 19 patients were nonselective. The response to therapy, evaluated retrospectively, was 67% and 16% in moderate and nonselective proteinuria(p=0.01). CONCLUSION: There is a significant relationship between selectivity of proteinuria and clinical para meters. Moreover, the selectivity of proteinuria has a predictive value on functional outcome.