Not initiated

The overall goals of this study are to demonstrate the change in renal tubular function in living donors pre and post nephrectomy at 6 months.

The physiologic sequelae of living kidney donation are still poorly understood. Uni-nephrectomy from donation results in decreased number of glomeruli and research has shown that there is glomerular hyperfiltration and glomerular hypertrophy. Uni-nephrectomy also results in a decreased number of tubules, but there is not much data about possible tubular injury post donation and its long term effects on donors.

Our overall hypothesis is that post uni-nephrectomy tubular function, measured by maximum urine concentration capacity, will be decreased and may be a more sensitive marker of kidney damage than standard tests, such as urine albumin, serum creatinine, estimated glomerular filtration rate (eGFR), or measured urine creatinine clearance (CrCl). The goal of this study is to evaluate the effect of uni-nephrectomy on renal tubular function and its potential in being an early and more sensitive marker in kidney injury when compared to standard tests.

Inclusion Criteria:

• Adult ≥18 years of age, who has been evaluated and approved as a potential living donor by the multi-disciplinary committee. All donors undergo a standard medical, social, and psychological pre- donation assessment
• Only patients who are able to sign their own consent form may be included in this study.
• Subjects must be able and willing, in the investigator's opinion, to complete all study requirements.

Exclusion Criteria:

• Subjects denied for donation for any medical, social or surgical reason to be living donor.
• Patients who are contraindicated or relatively contraindicated for DDAVP: a. patients with von Willebrand disease; b. Patients with habitual or psychogenic polydipsia; c. Patients with coronary artery insufficiency and/or hypertensive cardiovascular disease; d. Patients with conditions associated with fluid and electrolyte imbalance, such as cystic fibrosis, heart failure, and renal disorders; e. Patients predisposed to thrombus formation