[Status of treatment with free radical scavengers following kidney and pancreas transplantation].

AIM OF THE STUDY

The frequency of acute renal failure (ARF) after preservation and kidney transplantation is rather high. The etiology of an ARF is an interaction of multiple mechanisms as donor conditions, explantation procedure, duration of ischemia and reperfusion injury. Different experiments demonstrated, that the damage produced by reperfusion can be prevented by the scavenger of free radicals, the enzyme superoxide dismutase (SOD).

PATIENTS AND METHODS

After a double blind study, using consecutive intraarterial bovine SOD (n = 100) in kidney transplantation, showing a trend in favour to the SOD treated group, especially when long-time stored kidneys (> 30 h) had been grafted, a second study was designed to evaluate the efficiency of intravenous recombinant human SOD in the protection from ARF. This study (n = 180) was split into two different trials, double blind and randomized in itself: (A) grafts with cold ischemia time lower or equal 30 hrs., (B) cold ischemia more than 30 hrs. All grafts were preserved with Euro-collins. The study substances were either placebo or 200 mg rh-SOD (Grünenthal GmbH, FRG), given 10-2 minutes prior reperfusion intravenously. Parameters causing an ARF were equal and well comparable in both groups.

RESULTS

Concerning early graft function there was no difference in study A between placebo and rh-SOD group. In study B the average and median of the day creatinine dropped the first time without interference of hemodialysis, showed a trend in favour to the rh-SOD group. If placebo was given only 19% of the grafts gained function within the first week, when rh-SOD was applied 47% functioned in the first week. The lack of significant benefit from SOD treatment could be explained by the dependency of the proportion of the total injury caused by reperfusion compared with the proportion resulting from ischemic injury per se. The rh-SOD group showed a better 3 years graft survival rate (+16%).

CONCLUSIONS

It seems rh-SOD is able to augment the early graft function and is helpful to reduce the ARF frequency when long-time stored cadaveric kidneys have to be transplanted. These promising results encourage us to continue the study in protocol B to get greater numbers and definitive results.