The natural history of residual renal function in transplant donors.

After uninephrectomy, GFR in the remaining kidney increases to 60%-70% of the predonation value, largely because of a substantial increase in renal blood flow. Donor kidney function is then generally maintained over many years. Hypertension and proteinuria are common among living donors but do not appear to negatively affect long-term renal function. Loss of reserve capacity regarding renal function in some subgroups after donation, particularly in obese and older donors, raises questions about limitations of the renal adaptive response and suggests caution in generalization of current outcome data to more marginal donors not well represented in older studies.