Background
Monitoring of microbiological cause of infective endocarditis (IE) remains key in the understanding of IE; however, data from large, unselected cohorts are sparse. We aimed to examine temporal changes, patient characteristics, and in‐hospital and long‐term mortality, according to microbiological cause in patients with IE from 2010 to 2017.
Methods and Results
Linking Danish nationwide registries, we identified all patients with first‐time IE. In‐hospital and long‐term mortality rates were assessed according to microbiological cause and compared using multivariable adjusted logistic regression analysis and Cox proportional hazard analysis, respectively. A total of 4123 patients were included.
Staphylococcus aureus
was the most frequent cause (28.1%), followed by
Streptococcus
species (26.0%),
Enterococcus
species (15.5%), coagulase‐negative staphylococci (6.2%), and “other microbiological causes” (5.3%). Blood culture–negative IE was registered in 18.9%. The proportion of blood culture–negative IE declined during the study period, whereas no significant changes were seen for any microbiological cause. Patients with
Enterococcus
species were older and more often had a prosthetic heart valve compared with other causes. For
Streptococcus
species IE, in‐hospital and long‐term mortality (median follow‐up, 2.3 years) were 11.1% and 58.5%, respectively. Compared with
Streptococcus
species IE, the following causes were associated with a higher in‐hospital mortality:
S aureus
IE (odds ratio [OR], 3.48 [95% CI, 2.74–4.42]),
Enterococcus
species IE (OR, 1.48 [95% CI, 1.11–1.97]), coagulase‐negative staphylococci IE (OR, 1.79 [95% CI, 1.21–2.65]), “other microbiological cause” (OR, 1.47 [95% CI, 0.95–2.27]), and blood culture–negative IE (OR, 1.99 [95% CI, 1.52–2.61]); and the following causes were associated with higher mortality following discharge (median follow‐up, 2.9 years):
S aureus
IE (hazard ratio [HR], 1.39 [95% CI, 1.19–1.62]),
Enterococcus
species IE (HR, 1.31 [95% CI, 1.11–1.54]), coagulase‐negative staphylococci IE (HR, 1.07 [95% CI, 0.85–1.36]), “other microbiological cause” (HR, 1.45 [95% CI, 1.13–1.85]), and blood culture–negative IE (HR, 1.05 [95% CI, 0.89–1.25]).
Conclusions
This nationwide study showed that
S aureus
was the most frequent microbiological cause of IE, followed by
Streptococcus
species and
Enterococcus
species. Patients with
S aureus
IE had the highest in‐hospital mortality
.