(1) Background: The need to elucidate the microbial patterns in preservation fluid and explore their relationship with early infection-related events post kidney transplant and investigate antimicrobial resistance and the effects of preemptive antibiotic therapy. (2) Methods: This retrospective study analyzed the clinical data of 514 kidney transplant donors and 808 recipients from April 2015 to October 2020. Clinical data of donor and recipient characteristics, preservation fluid microbes, early infections (≤30 days), probable donor-derived infections (P-DDIs), antimicrobial resistance and preemptive antibiotic therapy was collected. (3) Results: The incidence of bloodstream (10.3% versus 5.2%, p = 0.006) and graft-site infections (9.7% versus 4.6%, p = 0.004) was significantly higher in recipients with culture-positive preservation fluid. In addition, recipients with ESKAPE pathogens or Candida species had a notably higher rate of bloodstream infections (14.1% versus 6.9%, p = 0.033) and graft-site infections (16.7% versus 3.5%, p < 0.01) than those with other positive pathogens. Preemptive antibiotic therapy decreased the bloodstream infection rate (11.8% versus 35.7%, p = 0.047) when preservation fluid was positive for ESKAPE pathogens. (4) Conclusions: Culture-positive preservation fluid has potential implications for kidney transplant recipients. ESKAPE pathogens or Candida species in preservation fluid as well as their antimicrobial resistance properties and non-preemptive antibiotic therapy could pose a risk of early infection-related events.

Background: Pediatric deceased donors offer great potential for expanding the organ donor pool. The utilization of pediatric donor kidneys has been explored by numerous transplant centers; however, the transplant outcome and risk factors have not been well elucidated. The aim of this study is to demonstrate the safety and risk factors of transplant outcome from pediatric deceased donors. Methods: We retrospectively analyzed 484 cases of single kidney transplantation (SKT) with pediatric donor kidneys performed at our center from January 2012 to March 2021. The recipients were grouped by age: child (≤12 years; n=143), adolescents (12–18 years; n=86), and adults (≥18 years; n=255). The overall prognosis of the recipients was analyzed, and the post-transplant outcomes were compared between the groups and assessed by univariate and multivariate analyses using the Cox proportional risk model. Results: The median follow-up time was 26.7 months. The 1- and 3-year patient survival rates were 98.7% and 96.8%, respectively. The 1- and 3-year death-censored graft survival (DCGS) was 96.1% and 92.7%, respectively. The overall estimated glomerular filtration rates (eGFRs) at 1 and 3 years were 80.0±24.5 and 84.2±25.2 mL/min/1.73 m²; the 3-year eGFR of the three groups were comparable and all were over 80 mL/min/1.73 m². Rejection was an independent risk factor for death-censored graft failure within 3 years after transplantation [hazard ratio (HR) =3.85; P=0.001], and was the primary cause of graft losses in the adolescent group. Thrombosis was more common within 1-month post-transplant in the child recipients (P<0.05), and its incidence was higher in recipients with donor body weight (DBW) ≤11 kg. Conclusions: SKT from pediatric donors can achieve decent outcomes. Rejection is an independent risk factor of graft survival, especially for adolescent recipients. Child recipients may compromise early transplant outcomes due to vascular thrombosis, which may be related to small (DBW ≤11 kg) pediatric donors.

(1) Calculated panel-reactive antibody (CPRA) is a measure of sensitization based on unacceptable antigens (UAs). Determination of UAs based on single-antigen bead assays at allele or antigen levels may be inappropriate. We aimed to introduce eplets for better assessment of sensitization; (2) 900 recipients and 1427 donors were enrolled for candidate or donor pools, respectively. Eplets were from the HLA Epitope Registry. UAs were determined by anti-HLA antibodies identified using LIFECODES Single Antigen (LSA) kits. CPRA values were calculated using a simplified method of donor filtering; (3) HLA antigens containing all eplets of an HLA antigen in LSA kits (LSA antigen) were defined as eplet-predicted (EP) antigens, the reactivity of which could be predicted by that LSA antigen. High reactivity concordance was found between LSA and EP antigens. More HLA antigens were covered by EP antigens in the population than LSA antigens. CPRA values at the EP level were higher than at the allele level and lower than at the antigen level. The EP antigens facilitated UA determination for non-LSA antigens and avoided acute rejection; (4) UA determination using EP antigens can lead to more accurate assessment of sensitization, enabling a high probability of compatible organs and a low risk of adverse outcomes.

Objective: To elucidate the risk stratification of gram-positive bacteria in the preservation fluid (PF), investigate antibiotic resistance and its role in early post-kidney transplant infections, and assess the efficacy of preemptive-anti-Gram-positive antibiotic (P-antiGP) therapy.Methods: This retrospective study analyzed the clinical data of 144 kidney transplant donors and 218 recipients between April 2015 and October 2020. Recipients with any of the high-virulence gram-positive bacteria (such as Enterococcus faecium, Enterococcus faecalis, and Staphylococcus aureus) in PF were defined as high-risk group. Recipients with other pathogens in PF were defined as low-risk group.Results: The high-risk group had a significantly higher incidence of infection events as compared with the low-risk group (42.6% vs. 26.2%, p = 0.014). Multivariate analysis indicated a trend toward an increased risk of early post-transplant infections in the high-risk group (adjusted OR = 1.855, 95% CI: 0.991–3.464, p = 0.052). Seven recipients (1.5%) were diagnosed as possible donor-derived infections (P-DDIs) and all of them were from the high-risk group. 56.4% (123/218) of recipients had multidrug-resistant organisms (MDROs) in PF and 12.4% (27/218) had extensively-resistant organisms (XDROs). The P-DDIs rate was notably higher in the extensively drug-resistant (XDR) group than non-XDR group (11.1% vs. 2.1%, p = 0.014). The incidence of P-DDIs was significantly lower (p = 0.025) in recipients with P-antiGP therapy (4.3%) as compared to recipients who did not (23.8%).Conclusion: E. faecium, E. faecalis, and S. aureus in PF are considered high-virulence gram-positive bacteria, and recipients with these pathogens are categorized as high-risk group. Additionally, a high prevalence of antibiotic resistance exists among gram-positive bacteria in PF, correlating with post-transplant infections. Furthermore, The addition of P-antiGP therapy as a preemptive therapy in the high-risk group can effectively reduce the incidence of P-DDIs.