SHORT-COURSE ANTIBIOTIC-THERAPY FOR RIGHT-SIDED ENDOCARDITIS CAUSED BY STAPHYLOCOCCUS-AUREUS IN INJECTION-DRUG USERS

Right-sided endocarditis caused by Staphylococcus aureus is a frequent complication of injection drug use. Fortunately, the prognosis for th is infection when treated with the standard regimen of 4 to 6 weeks od parenteral antistaphylococcal antibiotics is favorable. Nevertheless, in many cases, once drug users feel better, they leave the hospital a gainst medical advice before completing the full course of antibiotic therapy. This problem has stimulated interest in shortening the durati on of antibiotic treatment by adding an aminoglycoside antibiotic to a penicillinase-resistant penicillin. Data from in vitro synergy studie s and animal models of endocarditis suggest that S. aureus can be erad icated more quickly by combination therapy than by monotherapy. Report s of three prospective, nonrandomized clinical trials have been publis hed that support the use of a a-week course of a penicillinase-resista nt penicillin and an aminoglycoside antibiotic to treat uncomplicated, exclusively right-sided endocarditis caused by methicillin-susceptibt e S. aureus in injection drug users.