Characteristics and Risk Factors of Late-onset Bloodstream Infection beyond 6 Months after Liver Transplantation in Children

Background: Bloodstream infection (BSI) is a major cause of morbidity and mortality after pediatric liver transplantation (LT). However, most studies have focused on BSI occurring within a few months after LT. In this study, we evaluated the characteristics of BSI occurring beyond 6 months after pediatric LT. Methods: We conducted a retrospective cohort study at a pediatric LT center in Japan from November 2005 to March 2016. We evaluated the causative organisms and site of late-onset BSI in children ≤ 18 years of age. The risk factors for developing late-onset BSI and the associations of late-onset BSI with long-Term outcomes were also evaluated. Results: Three hundred forty cases of LT were evaluated. Thirty-eight BSI developed in 29 (9%) LT recipients. There were 42 organisms (nine Gram-positive cocci, 33 Gram-negative rods) isolated from the blood cultures of recipients with late-onset BSI. The most frequent sites of late-onset BSI was intraabdominal infection (18/38; 47%). There were also 14 (39%) episodes with no apparent focus. In multivariate analysis, a prolonged operative time > 12 hours (odds ratio [OR] = 3.55; P = 0.04) and biliary stenosis (OR = 4.60; P = 0.006) were independent risk factors for developing late-onset BSI. Late-onset BSI was associated with increased retransplantation rate (P = 0.04) and mortality (P < 0.001). Conclusion: Late-onset BSI developed in 9% of recipients after pediatric LT. Gram-negative rods accounted for the majority of late-onset BSI as a consequence of abdominal infection, but the focus was often unclear. Prolonged operative time at LT and biliary stenosis were independent risk factors for developing late-onset BSI.