Abstract:ObjectiveTo study the homology characteristics of clinicaly isolated and colonized linezolid(LZD)resistant Enterococcus faecalis (E. faecalis ) strains from a patient.MethodsTen E. faecalis strains (2 were isolated from urine specimens and 8 were from stool specimens) isolated from a patient with pulmonary infection were performed antimicrobial susceptibility testing, homology of E. faecalis was determined by pulsedfield gel electrophoresis (PFGE).ResultsBefore and after patients received LZD therapy, 2 E. faecalis strains isolated form urine specimens were both resistant to LZD (MICs: 8 mg/mL, 16 mg/mL, respectively), among 8 strains from stool specimens (6 were isolated before therapy, and 2 were isolated after therapy), LZD susceptible, intermediate, and resistant strains were 4, 2, and 2 respectively(MICs: 0.25-12 mg/mL). 10 strains of E. faecalis were homologous by PFGE typing. ConclusionIn this case, the detection of E. faecalis from urinary tract and intestinal tract is homologous, which suggested that LZDresistant Enterococcus may be colonized in vivo for a long time, and may be shift to cause bacterial infection.