Recurrence of bacteremia and infective endocarditis according to bacterial species of index endocarditis episode

PURPOSE: In patients surviving infective endocarditis (IE) recurrence of bacteremia or IE is feared. However, knowledge is sparse on the incidence and risk factors for the recurrence of bacteremia or IE. METHODS: Using Danish nationwide registries (2010-2020), we identified patients with first-time IE which were categorized by bacterial species (Staphylococcus aureus, Enterococcus spp., Streptococcus spp., coagulase-negative staphylococci [CoNS], 'Other' microbiological etiology). Recurrence of bacteremia (including IE episodes) or IE with the same bacterial species was estimated at 12 months and 5 years, considering death as a competing risk. Cox regression models were used to compute adjusted hazard ratios of the recurrence of bacteremia or IE. RESULTS: We identified 4086 patients with IE; 1374 (33.6%) with S. aureus, 813 (19.9%) with Enterococcus spp., 1366 (33.4%) with Streptococcus spp., 284 (7.0%) with CoNS, and 249 (6.1%) with 'Other'. The overall 12-month incidence of recurrent bacteremia with the same bacterial species was 4.8% and 2.6% with an accompanying IE diagnosis, while this was 7.7% and 4.0%, respectively, with 5 years of follow-up. S. aureus, Enterococcus spp., CoNS, chronic renal failure, and liver disease were associated with an increased rate of recurrent bacteremia or IE with the same bacterial species. CONCLUSION: Recurrent bacteremia with the same bacterial species within 12 months, occurred in almost 5% and 2.6% for recurrent IE. S. aureus, Enterococcus spp., and CoNS were associated with recurrent infections with the same bacterial species.