Timely diagnosis and antibiotic therapy in infective endocarditis: the impact of delays on mortality

Infective endocarditis (IE) is a severe condition with high mortality rates, where timely diagnosis and initiation of effective antibiotic therapy are critical for improving outcomes. Despite advancements in management, delays in therapy remain common due to the disease’s complex presentation.

To assess the impact of delays in effective antibiotic therapy and diagnosis on mortality in patients with IE. Also, to quantify the relationship between these delays and patient outcomes.

Retrospective study of 64 patients admitted for IE in a Cardiology Department. Baseline characteristics and microbiological findings were analyzed. Patients were divided into two groups based on in-hospital mortality. The variables analyzed were demographic and clinical characteristics, the number of days until effective antibiotic therapy and the number of days until diagnosis. Variables were compared between groups using Chi-square and Mann-Whitney U. Multivariate logistic regression was performed to assess the association between delays and mortality. ROC analysis was used to evaluate the predictive ability of variables.

Mean age was 68±8 years; 67,2% were men. In-hospital mortality was 25%. Patients who died experienced significantly longer delays in both effective antibiotic therapy and diagnosis. The mean delay to effective antibiotic therapy was 13.63 days for patients who died versus 3.77 days for survivors (p < 0.001). Similarly, the mean delay to diagnosis was 14.94 days for patients who died versus 5.42 days for survivors (p < 0.001).

Logistic regression analysis revealed that each additional day of delay to effective antibiotics increased the odds of mortality by 33.8% (OR 1.338, 95% CI: 1.020–1.754, p = 0.035). Delay to diagnosis was not significantly associated with mortality after adjusting for other factors (OR 1.082, 95% CI: 0.860–1.360, p = 0.502).

ROC analysis revealed that delays in effective antibiotic therapy are a strong predictor of mortality (AUC of 0.951, p < 0.001). The optimal cutoff for predicting mortality was 8.5 days, with a sensitivity of 93.8% and a specificity of 93.7% (Youden’s Index = 0.875).

This study highlights the critical importance of minimizing delays in initiating effective antibiotic therapy for patients with IE. Each additional day of delay to effective antibiotic therapy significantly increased the odds of in-hospital mortality by 33.8%, underscoring the direct impact of timely therapeutic intervention on patient outcomes. Although delays to diagnosis were longer in non-survivors, they were not independently associated with mortality after adjustment for other factors. These findings emphasize the need for streamlined clinical pathways and prompt initiation of targeted antibiotic therapy to improve survival in this high-risk population. Future research should focus on identifying and addressing barriers to early antibiotic initiation in clinical practice.