Serious staphylococcal infections with strains tolerant to bactericidal antibiotics.

The clinical response in 20 cases of serious staphylococcal infection was compared with the in vitro resistance or "tolerance" of the infecting Staphylococcus to killing by antibiotics used in treatment. Cases were divided into two groups: (1) patients who initially received nonbactericidal antibiotics (ten cases), and (2) patients who initially received bactericidal antibiotics with or without nonbactericidal antibiotics. Mortality due to uncontrolled staphylococcal infection was 40% (4/10) in group 1 as compared with no mortality (1/10) in group0) in group 1 as compared with no mortality (0/10) in group 2. The duration of positive cultures after start of therapy in group 1 (mean, 6.1 days) was significantly longer than that in group 2 (mean, 1.3 days). The duration of fever after start of therapy in group 1 was not significantly different when compared with group 2.