title: Native valve endocarditis caused by Corynebacterium striatum with heterogeneous high-level daptomycin resistance: collateral damage from daptomycin therapy?
abstract: We describe a patient who developed Corynebacterium striatum native valve endocarditis after receiving two 6-week courses of daptomycin for the treatment of methicillin-resistant Staphylococcus aureus bacteremia and osteomyelitis. The organism exhibited in vitro heteroresistance to daptomycin, with two subpopulations showing daptomycin susceptibility (MIC of ≤ 0.094 μg/ml) and high-level resistance to daptomycin (MIC of ≥ 256 μg/ml). The selection of daptomycin-resistant Gram-positive skin flora with the potential of causing invasive disease may be a concern during prolonged courses of daptomycin.
authors.affiliation: University of Houston College of Pharmacy, Department of Internal Medicine, Division of Infectious Diseases, Houston, Texas, USA. Truc.T.Tran@uth.tmc.edu
authors.forename: Truc T
authors.initials: TT
authors.lastname: Tran
authors.forename: Siraya
authors.initials: S
authors.lastname: Jaijakul
authors.forename: Cole T
authors.initials: CT
authors.lastname: Lewis
authors.forename: Lorena
authors.initials: L
authors.lastname: Diaz
authors.forename: Diana
authors.initials: D
authors.lastname: Panesso
authors.forename: Heidi B
authors.initials: HB
authors.lastname: Kaplan
authors.forename: Barbara E
authors.initials: BE
authors.lastname: Murray
authors.forename: Audrey
authors.initials: A
authors.lastname: Wanger
authors.forename: Cesar A
authors.initials: CA
authors.lastname: Arias
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy / Q000382:microbiology; D003352:Corynebacterium / Q000187:drug effects / Q000472:pathogenicity*; D017576:Daptomycin / Q000627:therapeutic use*; D024881:Drug Resistance, Bacterial; D004697:Endocarditis, Bacterial / Q000382:microbiology* / Q000473:pathology*; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects / Q000472:pathogenicity; D008875:Middle Aged; D010019:Osteomyelitis / Q000188:drug therapy / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D017576:Daptomycin