Vancomycin-Resistant Staphylococcus

To the Editor: Schwalbe and colleagues (April 9 issue) 1 described a patient who was treated for 10 weeks with vancomycin for device-associated peritonitis due to Staphylococcus haemolyticus . Their report demonstrated that this organism, initially susceptible to vancomycin according to modified macrodilution susceptibility testing, developed stepwise resistance to vancomycin during the course of therapy. Staphylococci have remained uniformly susceptible to vancomycin during 30 years of clinical use. The report by Schwalbe et al. represents the first time in vitro studies have extensively characterized an isolate relatively resistant to vancomycin. The presence in this patient of an indwelling foreign device may . . . No extract is available for articles shorter than 400 words.