Background: Living kidney donors loose half of their renal mass in a single
surgical event. After this loss, a series of compensations take place. Thus,
living kidney donors offer a unique opportunity to study the metabolic and
functional consequences resulting from loss of renal mass. The aim of this
study was to assess parathyroid hormone (PTH) in living kidney donors after unilateral nephrectomy.
Material/Methods: Between 1995 and 2005, 66 living donor open nephrectomies were performed. Physical examination, blood and urine tests and ultrasonography were performed prior to nephrectomy and at every 12 months post operation. We assessed basal PTH level. Donor mean age was 40.9 years (range 29-60). The donors were predominantly female (52.5%). 27 donors did not report for follow-up visits. Observation period ranged from 36 to 156 months post nephrectomy.
Results: Mean creatinine concentration increased from 0.89 mg/dl presurgery to 1.12 mg/dl at 36 months and to 1.1 mg/dl at 84 months post donation. Mean creatinine clearance according to Cockroft-Gault formula decreased from 94.27 ml/min before donation to 80.2 ml/min at 36 months and to 72.2 ml/min at 84 months after donating the kidney. One patient (2.6%) had a PTH level elevated to 94 pg/ml at 78 months post operation. His creatinine clearance according to Cockroft-Gault formula was 102 ml/min. We also observed a lowered PTH level in one patient at 52 months after nephrectomy.
Conclusions: Living kidney donation does not result in serious changes in
PTH levels in our investigated group. Further study with a longer observation period may be needed to evaluate parathyroid hormone imbalance in the long-term.

Keywords: Kidney Transplantation, Living Donors