Diagnostic methods current best practices and guidelines for histologic evaluation in infective endocarditis.

Infective endocarditis (IE) often presents diagnostic and therapeutic challenges and continues to cause high morbidity and mortality. Confirmation of the diagnosis of IE is important for the purposes of epidemiologic and clinical studies and is crucial for patient management. Despite recent advances in diagnostic techniques, about 10% of IE cases remain culture-negative. Because pathological examination of cardiac valves to demonstrate vegetations and valvular inflammation remains the gold standard for the diagnosis of IE, the role of the pathologist is often decisive, especially when bacteriologists fail to isolate a microorganism or when a microorganism that has been isolated may be a contaminant. Furthermore, the pathologist may play an important role in identification of previously unknown infectious agents.