Infective Endocarditis in Patients with Congenital Heart Disease: Pediatric and Young Adult Perspectives from a Tertiary Center

Objectives: This study aimed to evaluate the clinical, microbiological, echocardiographic, and surgical characteristics of pediatric and young adult patients diagnosed with definite infective endocarditis (IE) at a tertiary pediatric cardiology center. Methods: In this retrospective cohort study, we included 21 patients diagnosed with IE between January 2019 and December 2024, according to the Modified Duke Criteria. Demographic, clinical, microbiological, and echocardiographic data were analyzed. Outcomes and complications, including the need for surgery and mortality, were recorded. Patients with complex congenital heart disease were included even beyond 18 years of age due to ongoing pediatric cardiology follow-up. Results: The median age at diagnosis was 15 years (range: 4 months–35 years), and 85.7% had congenital heart disease. Blood cultures were positive in 61.9% of patients, with Candida species being the most common pathogens (33.3%). Vegetations were detected in 85.7% of patients, primarily affecting the pulmonary and aortic valves. Surgical intervention was required in 33.3% of cases. In-hospital mortality was 23.8%, with Candida -related IE accounting for 60% of deaths. Culture-negative IE occurred in 38.1% of cases, often associated with prior antibiotic use. One patient experienced a relapse within six months. Conclusion: Infective endocarditis in children and young adults remains a serious condition with high morbidity and mortality, especially among those with complex congenital heart disease and fungal infections. Candida -related IE is associated with particularly poor outcomes, highlighting the need for early diagnosis, aggressive treatment, and vigilant follow-up in high-risk populations.