Acute rejection following renal transplantation. Evidence that severity is the best predictor of subsequent graft survival time.

UNLABELLED

Timely recognition of risk factors influencing graft survival time following kidney transplantation could facilitate the development of clinical interventions that would increase the longevity of graft survival. To identify these risk factors, we performed a retrospective analysis of the clinical outcome of 1949 renal transplants performed at The Ohio State University Transplant Program between 22 September 1982 and 14 June 1996. The number of acute rejection (AR) episodes was most predictive of shorter graft survival time. The first AR episode severity (indexed using the difference between post-treatment serum creatinine (RxCr) and baseline serum creatinine (BCr), or DeltaCr = RxCr - BCr) was the best predictor of graft survival time (r = 0.27, p < 0.0001) in patients experiencing AR. Subsequent AR episodes occurred more frequently in patients with a higher DeltaCr. However, DeltaCr was the best predictor of graft survival time (r = 0.44, p < 0.0001) in patients who had only one AR episode. The severity of the first AR episode (DeltaCr) correlated with the risk of subsequent AR episodes, the severity of a second AR episode and the average of mean blood pressures obtained after, but not before, the first AR episode. Therefore, we conclude that the severity of the first AR episode was the best predictor of renal allograft survival time in all patients experiencing AR, independent of subsequent AR episodes and correlated with subsequent clinical events which also influence renal allograft survival time. Thus, early diagnosis and aggressive treatment of the first AR episode are warranted to minimize AR severity and thereby maximize subsequent graft survival time.

CONCLUSIONS

The severity of the first acute rejection episode following renal transplantation is the best determinant of graft survival time and correlates with subsequent clinical events which could further reduce graft survival time.