Bactericidal activity of vancomycin in cerebrospinal fluid

Intraventricular application of vancomycin is an effective therapeutic regi men for the treatment of shunt-associated staphylococcal ventriculitis, We examined the in vitro activity of vancomycin at high concentrations against Staphylococcus aureus ATCC 25923 and Staphylococcus epidermidis ATCC 12228 in human cerebrospinal fluid samples. Time-kill curves revealed equal effi cacies for concentrations of 10, 100, and 300 mu g/ml, and incubation times of 24 to 48 h were needed to achieve a 3 log(10) reduction of viable bacte ria, A concentration of 5 mu g/ml showed a slightly lower activity, but thi s difference was not significant, In an infant who was successfully treated for shunt-associated ventriculitis due to S. epidermidis by once-daily loc al administration of vancomycin (3 mg for 2 days and 5 mg for 4 days [0.5 t o 0.8 mg/kg of body weight]) the in vivo kill kinetics were similar to thos e for the in vitro results, These results support time-dose regimens that p rovide trough vancomycin levels of 5 to 10 mu g/ml.