Renal pathology in patients with reflux nephropathy. The turning point in irreversible renal disease.

In reflux nephropathy both interstitial and glomerular damage advances with an increase in the scarring grade even in macroscopically normal regions. Based on various histologic findings, sclerosis and the enlargement of glomeruli rapidly accelerate between stages c-a and c-b, as shown by the combined Smellie's scarring grade of the bilateral kidneys. These two steep histologic changes in stage c-b are followed by a remarkable reduction in renal function (DTPA-GFR) and an increase in the amount of urinary protein. These clinicopathological changes thus suggest that hemodynamic changes or overloading in the functional remnant nephrons possibly start in stage c-a. It is also suggested that glomerular enlargement is an index of progressive disease in reflux nephropathy. Among our specimens, most cases of glomerular sclerosis were global while focal segmental glomerulosclerosis was very rare. These findings thus suggest that the global sclerosis observed in our specimens is clearly different from focal segmental glomerulosclerosis.