Gram-negative bloodstream infections in hemodialysis patients: A retrospective study

Background: Bloodstream infections (BSIs) are an important cause of hospitalizations and mortality among hemodialysis (HD) patients. Epidemiology of these infections is changing, with increasing rates of Gram-negative pathogens, including resistant ones. Few studies have focused on the characteristics and outcomes of these infections. Objective: We aimed to document the causative pathogens of BSIs in HD patients and their clinical outcomes during 2008 - 2015, and to compare risk factors, clinical features, appropriateness of therapy, and outcomes between patients with Gram-negative vs. Gram-positive BSIs. Materials and methods: A single-center retrospective cohort study. Charts of 120 HD patients hospitalized with first BSI were reviewed. Results: A total of 120 patients were included, 61 episodes of Gram-negative (51.8%) and 59 episodes of Gram-positive bacteria (49.2%). Source of infection was significantly more likely to be urinary or abdominal among patients with Gram-negative infection. Otherwise, no statistically significant differences were documented between groups in terms of baseline characteristics, presentation of infection and outcomes. Most Gram-negative BSIs were caused by enterobacteriaceae, followed by Pseudomonas spp. Previous clinical or surveillance cultures added little to accurate prediction of the causative organism. Conclusion: In a cohort of HD patients with BSI, no significant differences were found between Gram-negative and Gram-positive BSIs, besides source of infection. A urinary or abdominal source strongly suggests a Gram-negative pathogen. Otherwise, patient's characteristics, clinical presentation, and previous cultures, all cannot accurately predict the causative pathogen of BSI, and broad-spectrum antibiotics should be used empirically.