Organ-Specific Monitoring of Solitary Kidney after Living Donation by Using Markers of Glomerular Filtration Rate and Urinary Proteins

Abstract

<b><i>Background:</i></b> Effective follow-up after living kidney donation is important for maintaining the renal function of the donor. We investigated whether the estimated glomerular filtration rate (eGFR) and urinary protein and enzyme levels can provide important information regarding the state of the remaining kidney after donor nephrectomy. <b><i>Methods:</i></b> Seventy-five living donations were included (prospective/retrospective) in the study. The following parameters were measured up to 1 year after donor nephrectomy: serum creatinine and cystatin C as markers of the GFR; the high-molecular-weight urinary proteins as markers of glomerular injury; and the low-molecular-weight urinary proteins and urinary enzymes as markers of tubular function. <b><i>Results:</i></b> One year after kidney donation, the creatinine and cystatin C values were 1.38-fold increased than their initial values, while the eGFR was 32% lower. At that time, 38% of donors had a moderate or high risk of CKD progression. The biochemical urinary glomerular and tubular kidney markers examined showed different behaviors. After a transient increase, the glomerular proteins normalized. Conversely, the detection of low-molecular-weight urinary proteins and enzymes reflected mild tubular damage at the end of the study period. <b><i>Conclusions:</i></b> Our findings suggest that for the evaluation of mild tubular damage, low-molecular-weight marker proteins should be included in the urine diagnostic of a personalized living kidney donor follow-up.

Combined Heart-Kidney Transplantation: Indications, Outcomes, and Controversies

“…In patients with either a congenital or acquired solitary kidney, eGFR calculation by creatinine or cystatin-c measurement is unreliable and may necessitate use of measured GFR. 19 , 20 , 21 , 22 In disease states such as end-stage cardiac amyloidosis, renal manifestations may be limited to proteinuria without significant impact on markers of GFR. 23 Determining the need for kidney transplantation in these patients requires additional expertise and decision making that is outside the scope of this paper.…”