Treatment of Streptomycin-Susceptible and Streptomycin-Resistant Enterococcal Endocarditis

Abstract

Fifty-six patients with enterococcal endocarditis received 4 wk of antimicrobial therapy with penicillin G and streptomycin (36 patients) or, if infections were streptomycin resistant, penicillin and gentamicin (20 patients). Compared with patients who had symptoms for < 3 mo., patients with symptoms for > 3 mo. had a higher relapse rate (0% vs. 44%; P < 0.001) and mortality (2.5% vs. 25%; P < 0.001). Patients with mitral valve endocarditis had a significantly higher relapse rate (25%) than patients with aortic valve infections (0%) (P < 0.01). Gentamicin-associated nephrotoxicity was more frequent (P < 0.001) among patients treated with > 3 mg/kg .cntdot. day of gentamicin than among those treated with .ltoreq. 3 mg (100% vs. 20%). Relapse and mortality rates did not differ significantly between patients treated with low-dose or high-dose gentamicin regimens. Patients who have had symptoms of enterococcal endocarditis for > 3 mo. or patients with mitral valve infection should receive at least 6 wk of antimicrobial therapy; patients without these high-risk factors can be treated for 4 wk.