Microbial Transitions in Infective Endocarditis Influence the Spectrum of Clinical Features and Functional Outcomes

Abstract

Background: The microbial landscape of infective endocarditis (IE) has evolved over time, with Staphylococcus species recognized as the predominant pathogens. This shift has complicated IE management, and its impact on clinical outcomes remains unclear. We investigated recent microbial trends and their relationship with clinical outcomes in patients with IE.

Methods and Results: This study retrospectively examined 222 consecutive patients with suspected IE who underwent transesophageal echocardiography. Fifty-six met the modified Duke criteria for definite IE and were included in the final analysis. Microbiological trends indicated a significant increase and decrease in Staphylococcus spp. (P=0.040) and Streptococcus spp. (P<0.001) abundance, respectively. Patients infected with Staphylococcus spp. were more frequently treated surgically (75%) than those with other pathogens. Despite being associated with more extensive intracardiac lesions, Staphylococcus correlated with better functional status at discharge, with the highest proportion of patients achieving modified Rankin Scale (mRS) scores of 0–3 (P=0.049). Multivariate logistic regression analysis identified surgical intervention (odds ratio [OR] 5.40; 95% confidence interval [CI] 1.25–23.27; P=0.024) and younger age (OR 0.94; 95% CI 0.90–0.99; P=0.031) as independent predictors of favorable outcomes (mRS score 0–3).

Conclusions: Staphylococcus spp. are predominant pathogens in IE and are frequently associated with intense intracardiac involvement. Age and appropriately timed surgical intervention correlated with improved functional outcomes, indicating that early recognition and individualized treatment strategies may enhance prognosis. Timely and pathogen-directed management are important in IE.