Characterization of beta-lactam antibiotic-induced vancomycin-resistant MRSA (BIVR) in a patient with septicemia during long-term vancomycin administration.
It was reported that some methicillin-resistant Staphylococcus aureus (MRSA) show resistance to vancomycin (VCM) and beta-lactam antibiotics; thus, they are termed beta-lactam antibiotic-induced VCM-resistant MRSA (BIVR). The VCM resistance of MRSA is induced by the administration of beta-lactam antibiotics, but this phenomenon can be difficult to detect in the clinical laboratory. We detected the BIVR strain in a 64-year-old man who had had a ventilator tube inserted directly into the windpipe during long-term VCM therapy. The patient was diagnosed with MRSA pneumonia and septicemia on July 5, 2007, and sulbactam/ampicillin (SBT/ABPC) was administered for 5 days. However, the fever recurred, and administration of VCM was resumed for 7 days from July 19. Fever developed again, and VCM was administered again for 14 days from September 30. BIVR and VCM-low-sensitive MRSA were isolated from blood on October 18 and 22, although the VCM trough concentration was 10.2 microg/ml. On October 27, we changed to a combination of fosfomycin (FOM) and arbekacin (ABK), and thereafter the fever quickly decreased and the clinical symptoms abated. We isolated five MRSA strains from the blood of the patient, three strains of VCM-sensitive MRSA, one strain of BIVR, and one strain of a VCM-low-sensitive MRSA. The DNA band patterns determined by pulsed-field gel electrophoresis were completely identical except for the VCM-low-sensitive MRSA, which was missing one band. Furthermore, the VCM-low-sensitive MRSA became sensitive to beta-lactam antibiotics. Our results indicate the possibility that long-term VCM therapy is one of the factors that allow BIVR or VCM-low-sensitive MRSA to emerge, and this allows VCM therapy for MRSA to fail.
Research Center for Anti-Infectious Drugs, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan.
Yoshio
Y
Yamaguchi
Hideaki
H
Hanaki
Chie
C
Yanagisawa
Yurika
Y
Ikeda-Dantsuji
Takeo
T
Hashimoto
Harunori
H
Yazaki
Keiko
K
Sugahara
Takashi
T
Yanagisawa
Hiroki
H
Kawajiri
Shizue
S
Sato
Aki
A
Ishizaki
Rika
R
Tachihara-Sato
Yasuhisa
Y
Takahashi
Taro
T
Ono
Yo
Y
Kageyama
Tomohumi
T
Kawaguchi
Akihiko
A
Tamura
Kazuhiko
K
Hagane
Keisuke
K
Sunakawa
D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D016470:Bacteremia / Q000188:drug therapy / Q000382:microbiology; D003982:Dibekacin / Q000031:analogs & derivatives / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005578:Fosfomycin / Q000627:therapeutic use; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000188:drug therapy / Q000382:microbiology; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000382:microbiology*; D013997:Time Factors; D014640:Vancomycin / Q000008:administration & dosage*; D020713:Vancomycin Resistance; D018440:beta-Lactam Resistance; D047090:beta-Lactams / Q000008:administration & dosage*
D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D005578:Fosfomycin; D003982:Dibekacin; D014640:Vancomycin; C031986:arbekacin