Introduction: The aim of our study was to evaluate the cumulative incidence of DGF in a children who received a kidney graft from a brain-dead donor, its impact on patient and graft survival, and to identify predictive risk factors of DGF.
Methods: A retrospective multicenter study was conducted including recipients under 18 years of age who underwent KTx from a brain-dead donor between January 1, 2015 and December 31, 2017. DGF was defined as the need for dialysis within the first week after KTx.
Data were obtained from the clinical records of the patients and from the Registry and Management System of Argentina (SINTRA) and were analyzed using MedCalc® Statistical Software version 20.014; 2021.
Results: We analyzed 239 KTx performed at 17 centers. Of the recipients 54.4% were male, median age at Tx was 13.7 yr (r: 2.8 -17.9), weight 30 kg (r: 7 - 82), BMI 17 Kg/m2 (r: 11 - 36). Etiology of ESRD: CAKUT 30%, glomerular diseases with risk of recurrence 24.3%, typical HUS 3.8%, others 29.7%, and unknown 12.2%. Pre-emptive KTx was performed in 18.8% of patients, 39.7% were receiving hemodialysis, and 30% peritoneal dialysis. Median of time on dialysis was 2.62 yr (r: 0.12 - 9.8).
Of the donors 70.7% were male, median age was 17.6 yr (r: 2.8 - 55), BMI 23 Kg/m2 (r: 17 - 35), BMI ratio donor/recipient 1:1.35, and pre-ablation serum creatinine 0.82 mg/dl (r: 0.6 - 2.6). Cause of death was trauma in 57%, vascular in 24%, and others in 19%. Cold ischemia time was 16.6 hours (r: 4.2 - 42), HLA mismatches ≼ 3: 54% and > 3:  46 %. Multiple-organ donor in 84.5%.
Overall, 59 patients (24.7%) developed DGF.
Patients without DGF had better graft survival at 1 (96% vs 78%) and 3 yrs of follow-up (89% vs 73%) p= 0.001. There were no significant differences in patient survival between both groups at the 3-year follow-up (95% vs 91%).
Incidence of early AR (90 days post Tx) was higher in patients with DGF (34.5% vs 10.6%) p= 0.0001.
In univariate analysis risk factors for DGF were: age at Tx ≽ 13.7 yr, male gender, glomerular disease with risk of recurrence, hemodialysis as prior to KTx, and time on dialysis ≽ 1 yr. In multivariate analysis independent risk factors for DGF were: time on dialysis > 1 yr (OR 9.2 - 95% CI 2.1 - 39) and age at KTx > 13.7 yr (OR 1.09 - 95% CI 1.01 - 1.18).
Conclusion: In our cohort, cumulative incidence of DGF was higher than that reported by other authors. Patients with DGF had worse graft survival than those without DGF. Shortening the time on dialysis seems to be a modifiable factor to reduce DGF.