Streptococcus milleri endocarditis complicated by myocardial abscess.

A patient with Streptococcus milleri endocarditis and myocardial abscess was bacteriologically cured after surgical intervention and six weeks of parenteral penicillin therapy plus two weeks of gentamicin therapy. Studies of the bacterial isolate suggest that gentamicin added no therapeutic advantage to the antimicrobial regimen. This case demonstrates that local cardiac suppurative complications can occur during endocarditis caused by S milleri, and suggests that speciation of alpha-hemolytic streptococci may in some instances complement antimicrobial susceptibility testing.