Determination of the nosocomial origin of vancomycin-resistant Enterococcus faecium strains recovered from stool specimens of hematology department patients.

Patients severely neutropenic, when hospitalized, occasionally receive sele ctive digestive decontamination, and the risk of vancomycin-resistant strai n selection is a drawback since glycopeptide resistance is often associated with betalactam and amino-glycosid resistance. Bacterial translocation can lead to multiresistant bacterial sepsis. Eighteen Enterococcus faecium str ains were collected from patients hospitalized in the leukemia unit of the Universitary Hospital of Lille (CHRU, Pr Bauters) between October 1992 and July 1997 and were studied. Nosocomial acquisition or endogenous origin wer e investigated to choose well-adapted prevention. All the vancomycin-resist ant strains were shown by Polymerase Chain Reaction having the van A gene. The clonality of these strains was investigated by Pulsed-Field-Gel-Electro phoresis after Sma I restriction. Pulsotype analysis showed variable homolo gy (52 %- 100 %). Our results do not show evidence of patient-to-patient E. faecium transmission and suggest vancomycin-resistant strains were indepen dantly selected by antibiotic therapy from individual fecal flora. Except w hen epidemic events or happen, this strain isolation is more related to ant ibiotic prescription than misuse of isolation techniques.