Nitroimidazole resistance genes (nimB) in anaerobic Gram-positive cocci (previously Peptostreptococcus spp.).
OBJECTIVE
To investigate metronidazole resistance and the prevalence of nitroimidazole (nim) genes in clinically isolated anaerobic Gram-positive cocci.


METHODS
Metronidazole susceptibility was determined in 99 strains of anaerobic Gram-positive cocci and PCR amplification for the nim gene carried out on 61 strains (metronidazole MIC > or =0.5 mg/L).


RESULTS
The nimB gene was detected in 34% (21/61) of the strains. These included two highly resistant Finegoldia magna strains (MICs >128 mg/L). The nimB gene was, however, also demonstrated in 90% (19/21) of susceptible strains.


CONCLUSIONS
Although the nimB gene may be implicated in the high-level metronidazole resistance in 2 F. magna strains, the alarmingly high prevalence of the nimB gene in anaerobic Gram-positive cocci cannot be directly associated with resistance and the possibility of a silent nimB gene should be considered.
Theron
Maria M
MM
Department of Medical Microbiology (G4), Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa. gnmbml.md@mail.uovs.ac.za
Janse Van Rensburg
Marais N
MN
Chalkley
Lynda J
LJ
D001426:Bacterial Proteins / Q000235:genetics*; D003428:Cross Infection / Q000382:microbiology; D024881:Drug Resistance, Bacterial; D004352:Drug Resistance, Microbial / Q000235:genetics*; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology*; D006095:Gram-Positive Cocci / Q000187:drug effects* / Q000235:genetics*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009593:Nitroimidazoles / Q000494:pharmacology*; D010462:Peptostreptococcus / Q000187:drug effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013019:South Africa
D001426:Bacterial Proteins; C103064:NimB protein, Bacteroides fragilis; D009593:Nitroimidazoles