Double adult renal allografts: A technique for expansion of the cadaveric kidney donor pool

Background. A major impediment to kidney transplantation is the current shortage of donor organs. Currently approximately 22,500 candidates are awaiting kidney transplantation, while the number of donors remains stable at approximately 3500 each year in the United States. Alternative approaches to traditional organ donor selection are necessary. In this setting we hypothesized that kidneys with reduced nephron mass from adult donors may provide satisfactory renal function if both donor kidneys are placed into a single recipient. Methods. Eighteen paired adult renal allografts were transplanted into nine adult recipients (DUAL). Recipient graft outcome variables were examined and compared with outcomes from single kidneys transplanted from randomly selected ''ideal'' donors younger than 50 years of age (CONT < 50) and ''expanded'' donors older than 60 years of age (CONT > 60) who underwent transplantation at our center. Results. Six-month serum creatinine levels in the three groups, DUAL (n = 9), CONT < 50 (n = 20), and CONT > 60 (n = 12), were 1.6 +/- 0.3, 2.3 +/- 0.3, and 4.1 +/- 0.9 mg/dl, respectively, (p < 0.0001) between CONT > 60 and the other two groups. Mean estimated creatinine clearance (ml/min/1.73 m(2)) was 43.2 +/- 3.4, 62.5 +/- 5.4, and 24.5 +/- 5.3 (p < 0.02). Graft and patient survival at last follow-up in DUAL was 100% compared with 95% in CONT < 50 and 75% graft and 83% patient survival in CONT > 60. Delayed graft function occurred in one of nine patients (11%) in DUAL group compared with 4 of 20 (20%) in CONT < 50 group and 6 of 12 (50%) in CONT > 60 group. Mean follow-up of patients in DUAL group was 6.6 months (range, 2 to 14 months). Conclusions. Double adult kidney transplants (DUAL) are associated with acceptable short-term graft function, graft survival, and patient survival when compared with transplanted kidneys from an ideal donor group (CONT < 50). Double renal allografts are a preferred use for donor kidneys with suboptimal nephron mass. Long-term follow-up is required to validate further the proposed approach.