Τhe Impact of Pre-Transplant Kidney Biopsy on the Evaluation of Prospective Living Kidney Donors

Abstract

Living kidney donation contributes to increasing the donor pool. Since safety and excellent outcomes of living kidney donors (LKD) are essential, renal biopsy must be part of the pre-transplant evaluation in donors with isolated urine abnormalities or other risk factors. We retrospectively collected data on potential living donors evaluated in the pre-transplant outpatient clinic of Laiko General Hospital of Athens between 2007 and 2022, who underwent a pre-transplant biopsy. Biopsy indications included microscopic hematuria, borderline proteinuria and comorbidities suggestive of chronicity. Those with glomerular diseases or chronic lesions were excluded from donation. We identified 59 potential living donors who underwent renal biopsy. Of these, 10 (16.9%) were male. Median age was 58 (IQR 51–63) years, while 23 (39%) were older than 60 years. 49 out of 59 (83%) had glomerular hematuria, 10 (16.7%) had proteinuria (150–300 mg/d). Out of the 59 donors, 21 (35.6%) were hypertensive, three (5.1%) had impaired glucose tolerance and seven (11.9%) had a BMI > 30 kg/m2. A total of 32 (54.2%) potential donors were accepted for donation. Eight (13.6%) had IgA nephropathy, 10 (16.9%) TBMD and nine (15.3%) had increased chronicity including secondary FSGS. When compared with a control group of donors who did not need a pre-transplant biopsy, those 32 who donated were more frequently hypertensive (p = 0.003), but had similar eGFR [61.3 (±10.4) vs. 61.9 (±13.8), p = 0.866] after a follow-up of 79 (36–114) months. Renal biopsy is a useful tool in the evaluation of prospective LKD. Thorough assessment of donors with isolated urine abnormalities and marginal donors is critical to ensure good post-donation outcomes.