[Development of gentamicin-resistant Small Colony Variants of S. aureus after implantation of gentamicin chains in osteomyelitis as a possible cause of recurrence].
OBJECTIVE
Recently, S. aureus small colony variants (SCVs) were reported to persist within cultured endothelial cells and to cause persistent and antibiotic resistant infections in humans. Because gentamicin can very reproducably select for electron transport deficient SCVs as shown in earlier in vitro experiments, we searched for SCVs in a patient with chronic osteomyelitis, who received gentamicin beads.


METHODS
Special culture and identification procedures for determination of SCVs were used, including testing of the S. aureus specific nuc gene, pulsed field gel electrophoresis (PFGE) as a typing method and characterization of the auxotrophism of the SCVs.


RESULTS
In a case of a 34-year-old patient with chronic osteomyelitis who had previously been treated with gentamicin beads, menadione auxotrophic S. aureus SCVs as well as wild type S. aureus were recovered in multiple bone specimen. All different colony types isolated from simultaneous or from sequential specimen were shown to be clonal by PFGE.


CONCLUSIONS
Recovery of S. aureus SCVs from a patient treated with gentamicin beads suggests that the slow release of gentamicin into the local environment may be an efficient way to select for and/or induce SCVs. These data should alert physicians to also consider SCVs when a treatment failure occurs in a patient that has received gentamicin beads.
von Eiff
C
C
Institut für Medizinische Mikrobiologie, Westfälische Wilhelms-Universität, Münster.
Lindner
N
N
Proctor
R A
RA
Winkelmann
W
W
Peters
G
G
D000328:Adult; D001426:Bacterial Proteins / Q000235:genetics; D002908:Chronic Disease; D004352:Drug Resistance, Microbial / Q000235:genetics; D004720:Endonucleases; D005260:Female; D014644:Genetic Variation; D005839:Gentamicins / Q000008:administration & dosage*; D006801:Humans; D008768:Methylmethacrylates / Q000008:administration & dosage*; D008826:Microbial Sensitivity Tests; D008836:Micrococcal Nuclease; D010019:Osteomyelitis / Q000188:drug therapy* / Q000382:microbiology; D012008:Recurrence; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics
D001426:Bacterial Proteins; D005839:Gentamicins; D008768:Methylmethacrylates; C030159:gentamicin-polymethylmethacrylate bead; C074002:nuc protein, staphylococcus; D004720:Endonucleases; D008836:Micrococcal Nuclease