Enteroccocus and Endocarditis

Abstract

Infective endocarditis (EI) produced by enterococci ranks third among infectious endocarditis and is a severe infection with usually subacute onset, often complicated with valvular lesions, systemic emboli and immunological changes. EI caused by enterococcus is produced in 90% of cases by Enterococcus faecalis and much less often by Enterococcus faecium or other species. Most cases are acquired in the community, but enterococcal EI can also be nosocomial. Enterococcal endocarditis is more common in the elderly or may appear against the background of some associated conditions: colorectal cancer, liver cirrhosis, diabetes, immunosuppressive treatments. Transthoracic echocardiography combined with blood cultures is the basis of the diagnosis of infective endocarditis, but in difficult cases, transesophageal ultrasound and new imaging methods such as computer tomography, PET-CT or cardiac MRI can be the solution for establishing the diagnosis. Enterococci are very tolerant to bactericidal antibiotics and their eradication requires prolonged therapy (up to 6 weeks) with synergistic bactericidal combination of cell wall inhibitors with aminoglycosides, they can also be resistant to many antibiotics, including beta-lactams, aminoglycosides and vancomycin. E. faecium is often resistant to vancomycin and beta-lactams. Linezolid may be effective in the treatment of vancomycin-resistant enterococcal endocarditis, but also daptomycin, dalbavancin and oritavancin seem promising.