Background: During recent years, an increasing number of transplant centers within the Eurotransplant organization have used histidine-tryptophan-ketoglutarate (HTK) solution instead of University of Wisconsin (UW) solution as their preferred cold storage solution for abdominal organ preservation. We report on our single-center experience on the outcome of imported kidneys preserved with either HTK or UW solution in relation to the duration of cold ischemia time (CIT).
Methods: Between July 1989 and July 1997, 323 cadaveric kidneys preserved with UW or HTK and imported as a result of an exchange within the Eurotransplant organization were transplanted at our institution. CIT was <24 hr in 216 kidneys (UW: n=174, HTK: n=42) and > or =24 hr in 107 kidneys (UW: n=67, HTK: n=40). Renal functional outcome was evaluated by comparing delayed graft function and initial non-function rates, daily urinary output, the evolution of serum creatinine, and creatinine clearance at 1, 3, 5, 7, and 14 days and at 1, 3, 6 and 12 months, and graft survival at 1 year after transplantation in relation to the type of cold storage solution and CIT < or > or =24 hr.
Results: Whereas the incidence of delayed graft function did not differ significantly between kidneys preserved for less than 24 hr in UW (18.6%) or HTK (26.2%), this rate increased to 50% in HTK kidneys compared to 23.9% in UW kidneys when CIT exceeded 24 hr (P=0.006). Mean serum creatinine and creatinine clearance values were better at 1 and 5 days postoperatively in kidneys preserved <24 hr with UW as compared to HTK (P<0.05). After 24 hr of CIT, HTK-preserved kidneys showed an impaired renal function, not only in the immediate postoperative phase but also at 1, 3, 6, and 12 months after transplantation (P<0.05). Graft survival at 1 year was 92.9% in UW vs. 87.5% in HTK kidneys preserved for <24 hr (NS), and 91% vs. 77.4% when CIT exceeded 24 hr (P=0.059).
Conclusions: From these single-center findings, it can be concluded that UW is superior to HTK in kidney preservation, particularly when CIT exceeds 24 hr.