[Culture-negative endocarditis: etiology, diagnosis, management and therapy]

Area of Science:

• Infectious Diseases
• Cardiology
• Microbiology

Background:

• Culture-negative endocarditis (CNE) poses significant diagnostic difficulties due to variable clinical presentations.
• Common causes of CNE include prior antibiotic use and the presence of fastidious microorganisms difficult to culture.
• Extended incubation periods and specialized culture techniques (e.g., chocolate agar, CO2 enrichment) are vital for detecting slow-growing bacteria.

Purpose of the Study:

• To outline the diagnostic challenges and management strategies for culture-negative endocarditis.
• To highlight the importance of advanced diagnostic tools and tailored treatment approaches in CNE.

Main Methods:

• Review of diagnostic approaches for CNE, including extended blood culture incubation and specialized microbiologic techniques.
• Emphasis on the role of echocardiography, particularly transesophageal echocardiography (TEE), for visualizing cardiac lesions.
• Application of diagnostic criteria, such as the Duke criteria, for accurate CNE diagnosis.

Main Results:

• Transesophageal echocardiography demonstrates high sensitivity in detecting vegetations and perivalvular complications in CNE.
• The Duke criteria offer high accuracy for diagnosing CNE, with global clinical judgment showing comparable sensitivity but lower specificity.
• Differential diagnoses, including nonbacterial thrombotic endocarditis and valvular sclerosis, must be considered.

Conclusions:

• Culture-negative endocarditis requires a comprehensive diagnostic approach, integrating clinical, microbiologic, and imaging data.
• Echocardiography, especially TEE, is indispensable for diagnosis and management of CNE.
• Antibiotic selection for CNE should be guided by patient demographics, epidemiologic history, and clinical findings suggestive of specific etiologic agents.