Incidence, distribution and clinical relevance of microbial contamination of preservation solution in deceased kidney transplant recipients: a retrospective cohort study from China

Abstract

Objectives: To determine whether microbial contamination of preservation solution (PS) in kidney transplantation is associated with donor-derived infections (DDIs). Methods: We retrospectively analysed data from 1077 deceased kidney transplant recipients of 560 donors. In all, 1002 PS samples were collected for microbiological assessment to establish the incidence and distribution of contamination. Comparisons between patients with contaminated PS and those with sterile PS were performed to assess the impact of microbial contaminations in perfusate on probable donor-derived infections (p-DDIs), and potential risk factors for p-DDIs were examined. Results: The contamination rate of PS was 77.8% (402/517). Bacterial species accounted for 85.6% (887/1036) of the total 1036 isolated microorganisms and 26.5% (275/1002) of the recipients' PS were contaminated by ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.). Enterococcus predominated the microbiological pattern. The incidence of infection was significantly higher in patients with microbial contamination than in patients with sterile PS (13.8% (107/776) versus 7.1% (16/226), p 0.006). The prevalence of p-DDIs was significantly higher in patients with ESKAPE contamination than in patients with other bacterial contamination in PS (7.2% (18/251) versus 1.0% (4/405), p 0.000). Univariate analysis indicated that ESKAPE contamination increased the risk of p-DDIs (p 0.001, OR 3.610, 95% CI 1.678–7.764). Multivariate analysis determined ESKAPE contamination as the only independent risk factor associated with p-DDIs (OR 3.418, 95% CI 1.580–7.393). Conclusions: The high rate of microbial contaminations in PS is unusual and probably due to poor surgical procedures. Patients whose PS are contaminated by ESKAPE pathogens could have a significantly increased risk of p-DDIs at early post-transplantation.