[Blood culture negative endocarditis: a diagnostic challenge]

Area of Science:

• Infectious Diseases
• Microbiology
• Molecular Diagnostics

Context:

• Blood culture negative endocarditis (BCNE) represents a significant clinical challenge, accounting for approximately 5% of endocarditis cases.
• Delayed diagnosis and treatment initiation in BCNE can negatively impact patient outcomes.
• Common etiologies include prior antimicrobial drug administration and the presence of slow-growing or non-cultivable organisms.

Purpose:

• To highlight the diagnostic difficulties in BCNE.
• To emphasize the critical role of identifying the etiologic agent in BCNE management.
• To explore the potential of molecular diagnostic tools in improving BCNE diagnosis.

Summary:

• BCNE diagnosis is often delayed, most commonly due to pre-sampling antimicrobial therapy.
• Slow-growing or non-cultivable organisms also contribute to negative blood cultures in endocarditis.
• Broad-range 16S rRNA PCR followed by sequencing and microorganism-specific PCR are promising molecular techniques for BCNE etiology identification.

Impact:

• Molecular tools like 16S rRNA PCR show promise for accurate and timely BCNE diagnosis.
• Successful identification of causative agents can lead to more targeted antimicrobial therapy.
• Incorporating molecular techniques into diagnostic criteria may improve the management and outcomes of BCNE patients.