부산대학교 도서관

ABSTRACTCommunity-type Staphylococcus aureusstrains that are positive for mecAand PBP2a but appear phenotypically susceptible to oxacillin are increasingly reported worldwide. Four S. aureusclinical isolates carrying the mecAgene with oxacillin MICs of <2 μg/ml were tested for oxacillin efficiency by population analyses and experimental thigh infections. These isolates harbored staphylococcal cassette chromosome mectype IV and belonged to two genotypes. Two of the four isolates were found by population analysis to be truly oxacillin susceptible. All four isolates exhibited significant reductions in the numbers of colonies grown after dicloxacillin treatment of experimental thigh infections, as also did a mecA-negative S. aureuscontrol strain. These observations indicate that some of the phenotypically oxacillin susceptible mecA-positive Staphylococcus aureusisolates may be at least partially responsive to oxacillin.