Vancomycin-intermediate Staphylococcus aureus with phenotypic susceptibility to methicillin in a patient with recurrent bacteremia.

Vancomycin-intermediate Staphylococcus aureus (VISA) are an emerging problem. We observed a statistically significant inverse relationship in the MICs of vancomycin and oxacillin in S. aureus isolates from a patient undergoing hemodialysis who received 26 weeks of treatment with vancomycin during November 1999 through April 2000. All isolates were mecA positive and were indistinguishable by pulsed-field gel electrophoresis. The evolving susceptibility patterns of this strain highlight the challenges of detecting and treating VISA infections.