title: Emergence and long-lasting persistence of linezolid-resistant Enterococcus faecium-ST117 in an oncohematologic patient after a nine-day course of linezolid.
abstract: We report the emergence and long-lasting persistence of linezolid resistance in an ampicillin-resistant Enterococcus faecium strain in the intestine of a neutropenic oncohematologic patient receiving chemotherapy. The patient was first colonized by an epidemic ampicillin-resistant E. faecium (ARE)-ST117 clustering into lineage 78. This clone exhibited resistance to levofloxacin, erythromycin and high-level resistance to streptomycin and gentamicin. After receiving treatment with several broad spectrum antibiotics for febrile neutropenia, a 9-day course of oral linezolid was administered once the patient developed bacteraemia by the same ARE colonizing clone. Linezolid-resistant ARE was detected 17 days later in the follow-up fecal samples and persisted 41 days after suppression of linezolid therapy. Resistance to linezolid was associated with G2576T transversion in the 23S rRNA and the presence of cfr gene was not detected. The persistence of G2576T-ARE strains, especially in oncohematologic patients with injured intestinal membranes, could increase the risk of bacteraemia.
authors.affiliation: 1 Servicio de Microbiología, Hospital Universitario Ramón y Cajal and Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS) , Madrid, Spain .
authors.forename: Ana María
authors.initials: AM
authors.lastname: Sánchez-Díaz
authors.forename: Claudio
authors.initials: C
authors.lastname: Cuartero
authors.forename: Sara
authors.initials: S
authors.lastname: Lozano
authors.forename: Juan Diego
authors.initials: JD
authors.lastname: Rodríguez
authors.forename: Juan Manuel
authors.initials: JM
authors.lastname: Alonso
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Quiles-Melero
authors.forename: Javier
authors.initials: J
authors.lastname: López
authors.forename: Rafael
authors.initials: R
authors.lastname: Cantón
authors.forename: Patricia
authors.initials: P
authors.lastname: Ruiz-Garbajosa
mesh_terms: D000081:Acetamides / Q000627:therapeutic use*; D000208:Acute Disease; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000627:therapeutic use; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects / Q000235:genetics*; D016984:Enterococcus faecium / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D016908:Gram-Positive Bacterial Infections / Q000150:complications / Q000188:drug therapy / Q000382:microbiology / Q000473:pathology; D006801:Humans; D007938:Leukemia / Q000150:complications / Q000188:drug therapy / Q000382:microbiology* / Q000473:pathology; D000069349:Linezolid; D008297:Male; D009503:Neutropenia / Q000150:complications / Q000188:drug therapy / Q000382:microbiology / Q000473:pathology; D023303:Oxazolidinones / Q000627:therapeutic use*; D017354:Point Mutation; D012338:RNA, Ribosomal, 23S / Q000235:genetics*
chemical_list: D000081:Acetamides; D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents; D023303:Oxazolidinones; D012338:RNA, Ribosomal, 23S; D000069349:Linezolid