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.