The renal sinus during allograft rejection: sonographic and histopathologic findings.

Overview

In fourteen renal allografts, the sonographic appearance of the renal sinus was correlated with the histopathologic findings. In each allograft specimen, the histologic changes in the renal sinus were compared with those in the renal cortex. Except for one case (hyperacute rejection), the histologic rejection changes were of similar severity within the cortex and renal sinus. When the renal sinus histologic changes of rejection were considered to be minimal (three patients), the sonographic appearance of the renal sinus was classified as normal. With moderate histologic changes in the renal sinus (five patients), the sonographic findings in four patients were considered moderate, with a change in spatial distribution resulting in a coarse and uneven distribution of renal sinus echoes. When the renal sinus histologic changes of rejection were interpreted as severe (six patients), the sonographic findings were similarly more advanced. Except for a very few intense echoes distributed in an irregular pattern, the area of the renal sinus blended with the adjacent parenchyma. The study demonstrated a good correlation between histology and sonography of the renal sinus during allograft rejection, and promises reliable prediction of the severity of the rejection process using a noninvasive, rapid, and relatively simple approach.