RENAL DONATION is associated with both benefits and risks. Potential donors may benefit from the discovery of treatable health risks. Those who do donate describe a unique, personally uplifting experience. The recipient of a living, related transplant usually achieves restoration of renal function and the lowest morbidity of all forms of renal replacement therapy. Society benefits from the lowest cost of available treatments for end stage renal disease, and the greatest likelihood of the person's return to employment. Risks of donation are substantial, and include those of the medical evaluation, the surgery and operative recovery period, and the remainder of life with a single kidney. The risks and complications of the evaluation and surgery have been studied and defined. Compensatory renal growth immediately and for several years after unilaterial nephrectomy results in approximately 70% of preoperative glomerular filtration rate and renal plasma flow. Rat studies performed over the past 50 yr, and in an accelerated fashion in the past 5-15 yr, reveal that the natural age-associated proteinuria and glomerular sclerosis common to most rodent species is accelerated by unilateral nephrectomy. The acceleration of glomerular sclerosis has recently been attributed to adaptive increases in glomerular perfusion and filtration, and alterations in protein size-and charge selectivity of the capillary basement membrane demonstrated in rats with five-sixths or more surgical ablation of the kidney. Acceleration of diabetic glomerulosclerosis has been demonstrated in the uninephrectomized rat with streptozocin-induced diabetes, and a parallel has been suggested to Type I human diabetes with its known, early hyperfiltration. A dissimilar pattern of glomerular sclerosis appears after the age of 40 in normal human kidneys, unasociated with proteinuria, but associated with a well defined, inadequately explained, disproportional decrement in renal function. It has been suggested that unilateral nephrectomy, with resultant known increase in blood flow and filtration of the remaining kidney, may also accelerate glomerular sclerosis in normal man. Studies of donors up to 4 yr after donation fail to support this suggestion. Critical studies of donors 10-20 yr and longer after nephrectomy are necessary to examine this hypothesis.

Normal living humans have been utilized for kidney transplantation since the first identical twin renal transplant at Peter Bent Brigham Hospital in 1955. 1 Since then, many thousands of living donor renal transplants have been performed worldwide. The latest US data indicate that 1275 or 27.1% of 4697 kidney transplants in 1980 were from related living donors. 2 In Europe, where cadaver organs have historically constituted a higher proportion of transplanted kidneys, 375, or 15.2% of 2469 reported transplants in 1978 were from living donors. 3 Until 1974, the Human Renal Transplant Registry, maintained by the American College of Surgeons, afforded a valuable data source concerning transplantation in the US Unfortunately, the Endstage Renal Disease (ESRD) Medical Information System (MIS) maintained by the Health Care Financing Administration (HCFA) has provided little information other than individual transplant center and cumulative transplant activity data, precluding any analysis in depth concerning transplantation or renal donation in the past 8 yr. The last report of the Human Renal Transplant Registry, 4 and single center reports, 5.6 however, indicate that siblings and parents account approximately equally for the vast majority of living renal donations. Children past their minority, more distant blood relatives, and occasionally wives, husbands …