Phenotypes and genotypes of vancomycin-resistant enterococci isolated during long-term follow-up in a patient with recurrent bacteremia and colonization.
Twenty-seven isolates of vancomycin-resistant enterococci were obtained at monthly intervals from a bed-ridden man with hypoxic encephalopathy. During the 28-month period of the patient's hospitalization, 3 episodes of bacteremia and one episode of catheter-related infection caused by vancomycin-resistant enterococci occurred. Rectal swabs showed colonization of vancomycin-resistant enterococci for more than 2 years. Three months after termination of antimicrobial therapy, the rectal colonization for vancomycin-resistant enterococci was eradicated. Four species (Enterococcus faecium, Enterococcus gallinarum, Enterococcus faecalis, and Enterococcus casseliflavus) were identified among the 27 vancomycin-resistant enterococcus isolates. Three non-clonal related patterns were found among 17 strains of E. faecium by pulsed-field gel electrophoresis. All of the 3 E. faecalis isolates were of the VanB phenotype, but of the vanA genotype. Linezolid had the most potent in vitro activity against these vancomycin-resistant enterococcus isolates, with minimum inhibitory concentrations >2 microg/mL. Eighty-five percent of these vancomycin-resistant enterococcus isolates were susceptible to tetracycline and 66% were susceptible to quinupristin-dalfopristin. Although a high genetic correlation of E. faecium was identified in the patient with prolonged hospitalization, the isolation of 3 genetically unrelated colonized isolates suggested a lack of correlation between infection and colonization. Precautions against resistant organisms, adapted antibiotic policies, and elimination of patient carriage are useful for controlling the spread of vancomycin-resistant enterococci.
Yeh
Kuo-Ming
KM
Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
Lu
Jang-Ji
JJ
Siu
Leung-Kei
LK
Peng
Ming-Yieh
MY
Chang
Feng-Yee
FY
D000900:Anti-Bacterial Agents / Q000145:classification / Q000627:therapeutic use; D016470:Bacteremia / Q000188:drug therapy / Q000382:microbiology*; D001426:Bacterial Proteins / Q000032:analysis; D019729:Carbon-Oxygen Ligases / Q000032:analysis; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field / Q000379:methods; D016983:Enterococcus / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D005500:Follow-Up Studies; D005838:Genotype; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy / Q000382:microbiology*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D010641:Phenotype; D016133:Polymerase Chain Reaction / Q000379:methods; D012008:Recurrence; D013045:Species Specificity; D020713:Vancomycin Resistance / Q000235:genetics*
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C071437:VanA ligase, Bacteria; C079913:VanB protein, Enterococcus; D019729:Carbon-Oxygen Ligases