Abstract 1964

The goal of this study is to develop a method for measuring glomerular hyperfiltration in a clinical setting. Experimental and clinical data support the hypothesis that glomerular hyperfiltration, an adaptive hemodynamic response to loss of functioning nephrons, contributes to destruction of the residual nephrons. Although intervention with ACE inhibitors may be helpful, the measurement of glomerular hyperfiltration usually requires relatively invasive and expensive methods. Renal reserve filtration capacity is an index for glomerular hyperfiltration. We have used a cimetidine protocol for creatinine clearance to measure the baseline and post protein meal GFR in 5 normal and 22 pediatric renal patients. The table shows the children divided into three groups as was done by Cleper et al (Pediatric Nephrol (1997);11:473-476). The RRFC is defined as the percent change of the baseline GFR following the protein meal. The subjects were categorized as those with >20% RRFC, 10-20% RRFC and <10% RRFC.

Table 1 No caption available
Full size table

This protocol makes it feasible to identify children with glomerular hyperfiltration in a clinical setting. With accumulation of sufficient data, the measurement of RRFC may provide a basis for identifying children with renal damage who are in a state of persistent glomerular hyperfiltration and who might benefit from treatment with an ACE inhibitor. It is important to recognize that a measurement of GFR per se does not indicate the presence or absence of glomerular hyperfiltration.