Restrospective correlation of clinical and histologic findings of 189 exchanged kidneys

Tissues samples from 189 unsuccessful renal allografts, 47 recovered at autopsy and the others removed surgically, were examined histologically by light microscopy. Tissues samples were obtained from cadaver kidneys that had been exchanged regionally for transplantation. Each allograft tissue sample was rated as to extent of pathologic changes denoting rejection and was classified accordingly. Surgical and autopsy reports, as well as clinical data, were then obtained and these were compared with the retrospective pathologic findings of this study. Our pathologic findings agreed with the original pathologic diagnosis as to presence or absence of rejection changes in 180 cases, but disagreed with the clinical diagnosis of rejection in 28 of the 63 cases with minimal or no histologic evidence of rejection. There was less disagreement with the clinical diagnosis for the 87 cases with histologic evidence of rejection which had been judged as sufficient to cause allograft loss, 70 having been clinically diagnosed as rejected. Disagreement occurred most often where the allograft had never functioned or had been lost within 3 months. Retrospective analysis did not disclose any association between rejection histology and preformed antibodies or length of kidney perfusion time. Sufficient allografts appeared to have been lost for reasons other than rejection to cast doubt on the validity of interpreting renal allograft data only by graft survival statistics.