Enterococcal Infections

(See also the American Heart Association's Infective Endocarditis in Adults: Diagnosis, Antimicrobial Therapy, and Management of Complications.)

Enterococci associated with endocarditis are difficult to eradicate unless a combination of certain cell wall–active drugs (eg, penicillin, ampicillin, amoxicillin, piperacillin, vancomycin) plus an aminoglycoside (eg, gentamicin, streptomycin) is used to achieve bactericidal activity. However, some cell wall–active drugs have limited or no activity against enterococci; they include nafcillin, oxacillin, ticarcillin, ertapenem, most cephalosporins, and aztreonam. E. faecium are more resistant to penicillin than E. faecalis. When an aminoglycoside cannot be used, the combination of an aminopenicillin, such as ampicillin, plus ceftriaxone is an effective alternative for the treatment of E. faecalis endocarditis. Imipenem and, to a lesser degree, meropenem are active against E. faecalis.

For complicated skin infections due to vancomycin-susceptible enterococci, daptomycin, linezolid, tedizolid, tigecycline, and omadacycline are effective treatment options.

Piperacillin/tazobactam, imipenem or meropenem, tigecycline, and eravacycline are recommended for complicated intra-abdominal infections when enterococci are known or presumed to be involved.

Urinary tract infections do not require bactericidal therapy and, if the causative organism is sensitive, are usually treated with a single antibiotic such as ampicillin. Nitrofurantoin and fosfomycin are often effective against vancomycin-resistant enterococcal urinary tract infection.

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.