Effect of donor kidney volume on recipient outcome:  does the "dose" matter?
BACKGROUND
The effect of donor kidney volume on recipient kidney function has not been fully evaluated.


METHODS
We performed a prospective analysis of 125 consecutive living kidney donor/recipient pairs. Donor kidney volume was calculated from pretransplantation computed tomography angiograms using a three-dimensional computerized volume method. Cortical volume was calculated from arterial phase and total volume from delayed phase. Because weight is a surrogate marker for metabolic demands, we looked at the "volume dose" by calculating the ratio of donor kidney volume to recipient weight. Recipient kidney function was assessed by calculating the estimated glomerular filtration rate (eGFR) using the Chronic Kidney Disease Epidemiology Collaboration formula. Logistic regression models were used to evaluate odds of developing eGFR of <60 mL/min per 1.73m(2) (eGFR<60) at 12 months.


RESULTS
Because cortical and total volumes were correlated (R=0.734, P<0.001), we used total kidney volume to evaluate the dose effect. The mean donated volume dose (SD) was 2.13 (0.62) mL/kg. The mean recipient eGFR at 12 months was 63.6 (17.3) mL/min per 1.73 m, and it correlated with volume dose (r=0.341, P<0.001). Compared with the lowest tertile, those in the highest tertile of donor kidney volume to recipient weight had lower odds ratio of developing eGFR of less than 60 mL/min per 1.73 m(2) (odds ratio, 0.23; 95% confidence interval, 0.07-0.81) in a multivariate logistic regression model. Spline regression suggested that a volume dose greater than 2.5 mL/kg was associated with lowest risk of eGFR of less than 60 mL/min per 1.73 m(2) at 12 months.


CONCLUSIONS
Donor kidney volume dosing is an important determinant of recipient graft outcomes and may predict recipient kidney function in kidney transplantation.
Division of Nephrology, Transplant Program, University of Utah, 30 N. 1900 E., Salt Lake City, UT 84132, USA.
Magdalena B
MB
Sikora
Akram
A
Shaaban
Srinivasan
S
Beddhu
Hassan
H
Bourija
Guo
G
Wei
Bradley
B
Baird
Crystal M
CM
Truax
Fuad S
FS
Shihab
D000328:Adult; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D021621:Imaging, Three-Dimensional; D007668:Kidney / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D016030:Kidney Transplantation / Q000009:adverse effects; D019520:Living Donors; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D009929:Organ Size; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D055815:Young Adult