Long-term outcomes and risk factors for early bacterial infection after pediatric liver transplantation: a prospective cohort study

Abstract

Background: Liver transplantation (LT) is the most efficient treatment for pediatric patients with end-stage liver diseases, while bacterial infection is the leading reason for posttransplant mortality. The present study is to explore the outcomes and risk factors of early bacterial infection (within 1 mo) after pediatric LT. Methods: In this prospective cohort study, 1316 pediatric recipients (median [IQR] age: 9.1 [6.3-28.0] months; male: 48.0%; median [IQR] follow-up time: 40.6 [29.1-51.4] months) who received LT from September 2018 to April 2022 were included. Bacterial culture samples such as sputum, abdominal drainage, blood and so on were collected when recipients were presented with infective symptoms. Kaplan-Meier analysis was applied to estimate the long-term survival rates and logistic regression was used to identify independent risk factors. To explore the role of pretransplant rectal swab culture (RSC) in reducing posttransplant bacterial infection rate, 188 infant LT recipients (median [IQR] age: 6.8 [5.5-8.1] months; male: 50.5%) from May 2022 to September 2023 were included. Log-binomial regression was used to measure the association of pretransplant RSC screening and posttransplant bacterial infection. The “Expectation Maximization” algorithm was used to impute the missing data. Results: Bacterial infection was the primary cause for early (38.9%) and overall mortality (35.6%) after pediatric LT. Kaplan-Meier analysis revealed inferior 1- and 5-year survival rates for recipients with posttransplant bacterial infection (92.6% vs. 97.1%, 91.8% vs. 96.4% respectively; P<0.001). Among all detected bacteria, Staphylococcus spp. (34.3%) and methicillin-resistant coagulase-negative Staphylococci (43.2%) were the dominant species and multi-drug resistant organisms, respectively. Multivariable analysis revealed that infant recipients (adjusted odds ratio [aOR], 1.49; 95% CI, 1.01-2.20), male recipients (aOR, 1.43; 95% CI, 1.08-1.89), high graft-to-recipient weight ratio (aOR, 1.64; 95% CI, 1.17-2.30), positive posttransplant RSC (aOR, 1.45; 95% CI, 1.04-2.02) and nasopharyngeal swab culture (aOR 2.46; 95% CI, 1.72-3.52) were independent risk factors for early bacterial infection. Furthermore, RSC screening and antibiotic prophylaxis before transplantation could result in a relatively lower posttransplant infection rate, albeit without statistical significance (adjusted RR, 0.53; 95% CI, 0.25-1.16). Conclusion: In this cohort study, posttransplant bacterial infection resulted in an inferior long-term patient survival rate. The five identified independent risk factors for posttransplant bacterial infection could guide the prophylaxis strategy of posttransplant bacterial infection in the future. Additionally, pretransplant RSC might decrease posttransplant bacterial infection rate.