Staphylococcus epidermidis Endocarditis

Incidence and Risk Factors

• Staphylococcus epidermidis is the most common organism in early prosthetic valve endocarditis (within 2 months after surgery), according to the American College of Cardiology 1, 2
• In native valve endocarditis, S. epidermidis accounts for only about 5% of cases, typically affecting patients with pre-existing valvular heart disease, particularly mitral valve prolapse, as reported by the American Heart Association 3, 4
• Healthcare-associated procedures involving intravascular devices significantly increase the risk of S. epidermidis endocarditis, as stated by the European Society of Cardiology 5, 1

Clinical Presentation and Course

• Native valve endocarditis caused by S. epidermidis typically follows an indolent course with a satisfactory response to medical or surgical therapy, according to the American Heart Association 4
• Prosthetic valve endocarditis caused by S. epidermidis often presents with fever, as reported by the American College of Cardiology 6

Diagnostic Approach

• The modified Duke criteria should be used for diagnosis, with S. epidermidis blood cultures considered a major criterion only when multiple positive cultures are obtained, as recommended by the American College of Cardiology 2, 6
• Transesophageal echocardiography is particularly important for detecting vegetations and complications in suspected prosthetic valve endocarditis, according to the American College of Cardiology 1, 2

Special Considerations

• S. epidermidis should be distinguished from S. lugdunensis, which causes a more virulent form of endocarditis with higher rates of perivalvular extension and metastatic infection, as reported by the American Heart Association 4
• Blood cultures may need to be incubated for longer periods to detect S. epidermidis in some cases of culture-negative endocarditis, as stated by the American Heart Association 7