Category: Imaging & Image Guided Therapy: New Therapies
Introduction & Objective :
High donor Body Mass Index (BMI) has long been recognized as a risk factor for kidney donation. Recent data has shown a significant short-term decline in donor renal function in patients with an elevated visceral adipose tissue (VAT) to subcutaneous adipose tissue ratio on preoperative computerized tomography (CT). In this study we evaluated the relationship between VAT with histologic changes in the donor kidney and mid-term renal function decline in living kidney donors.
VAT was measured on pre-donation CT scans at a single lumbar level in 210 donors from 2010 to 2015. Kidney histology, obtained from implant biopsy during transplant, was available in 162 patients. Chronic histologic change was defined as the presence of at least 2 of the following 3 features: > 5% global glomerulosclerosis, interstitial fibrosis, or arteriosclerosis. The decline in renal function from pre-donation to 2 years post-donation was assessed using estimated glomerular filtration rate (eGFR) with paired T-testing, repeated measures analysis (MANOVA), and linear regression analyses.
Mean donor age was 42 and 60% were female. Mean BMI and VAT were 27±3 kg/m2 and 96±64 cm2, respectively. On univariate linear regression there was a significant association between elevated VAT and decreased recovery of renal function, (p < 0.0001, Figure 1). On MANOVA, high VAT predicted decreased renal recovery at 1, 6, 12, and 24 months (p=0.03). Biopsies from donors with high VAT were more likely to have chronic histologic changes than donors with low VAT (p < 0.001, Figure 2). On univariate analyses both BMI and VAT were associated with chronic histologic change and decreased renal function recovery, however, on multivariate analyses VAT remained independently associated with both outcomes, while BMI did not.
Preoperative VAT appears to be a more significant indicator of long-term renal decline in kidney donors than BMI. This is further evidenced by the chronic histologic changes seen in kidneys from donors with high VAT. Morphometrics, including the measurement of VAT, should be incorporated into the standard preoperative evaluation of potential kidney donors.
Karen Stern– Clinical Fellow, Cleveland Clinic Foundation, Cleveland, Ohio
Sherif Armanyous– MD, Cleveland Clinic Foundation, Cleveland, Ohio
Erick Remer– Cleveland Clinic Foundation, Cleveland, Ohio
Ryan Ward– Cleveland Clinic Foundation, Cleveland, Ohio
Joshua Augustine– Cleveland Clinic Foundation, Cleveland, Ohio
Emilio Poggio– Cleveland Clinic Foundation, Cleveland, Ohio
Venkatesh Krishnamurthi– Cleveland Clinic Foundation, Cleveland, Ohio
Manoj Monga– Head of the Endourology Unit, Cleveland Clinic Foundation, Cleveland, Ohio
Cleveland Clinic Foundation
Karen Stern MD is currently an Advanced Endourology and Stone Disease Fellow at the Glickman Urological & Kidney Institute of the Cleveland Clinic. She received her BA from Emory University, her medical degree from the University of Arizona and completed her Urology residency at the Mayo Clinic in Phoenix, Arizona. She previously served as the Resident Representative for the Western Section of the AUA and as the Chair of the Residents and Fellows Committee (RFC). She is currently the RFC Representative on the AUA Young Urologists Committee. She is a Mayo Clinic Scholar and will be returning to Mayo Clinic Arizona as a Senior Associate Consultant in July 2019.