Antimicrobial Susceptibility of Microorganisms Isolated from Periapical Periodontitis Lesions.
Periapical periodontitis usually results from microbial infection, with these microorganisms occasionally migrating to the root canal, which can lead to further, potentially life-threatening, complications. Here, the susceptibility of 27 bacterial strains to various antimicrobial agents was evaluated. These strains comprised 13 species; 16 of the strains were clinical isolates from periapical lesions. Each strain was inoculated onto blood agar plates containing one of the antimicrobial agents. The plates were incubated anaerobically at 37°C for 96 hr and the minimal inhibitory concentrations (MICs) determined. Ten strains required an MIC of 32 μg/ml or greater for amoxicillin, 6 for cefmetazole, and 5 for cefcapene among β-lactam antibiotics; 8 strains required an MIC of 32 μg/ml or greater for clindamycin, 4 for azithromycin, and 11 for clarithromycin among macrolide antibiotics; 3 strains required an MIC of 32 μg/ml or greater for ciprofloxacin and 2 for ofloxacin among fluoroquinolones. The effect of cefcapene on 5 strains was evaluated after biofilm formation to investigate the relationship between biofilm formation and susceptibility. All strains showed a decrease in susceptibility after biofilm formation. The results revealed that several antimicrobial agents commonly used in a clinical setting, including amoxicillin, cefmetazole, and clindamycin, are potentially effective in the treatment of orofacial odontogenic infections. The development of resistant strains, however, means that this can no longer be guaranteed. In addition, azithromycin, ciprofloxacin, and ofloxacin were more effective than the 3 β-lactam antibiotics tested. These results suggest that sensitivity testing is needed if odontogenic infections are to be treated safely and effectively.
Department of Oral and Maxillofacial Surgery, Tokyo Dental College.
Masato
M
Narita
Takahiko
T
Shibahara
Nobuo
N
Takano
Rie
R
Fujii
Katsuji
K
Okuda
Kazuyuki
K
Ishihara
D000190:Actinomyces / Q000187:drug effects; D000658:Amoxicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D017963:Azithromycin / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects; D002167:Campylobacter / Q000187:drug effects; D015311:Cefmetazole / Q000494:pharmacology; D002511:Cephalosporins / Q000494:pharmacology; D002939:Ciprofloxacin / Q000494:pharmacology; D017291:Clarithromycin / Q000494:pharmacology; D002981:Clindamycin / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D045182:Fusobacteria / Q000187:drug effects; D006190:Haemophilus / Q000187:drug effects; D006801:Humans; D007709:Klebsiella / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin / Q000494:pharmacology; D010485:Periapical Periodontitis / Q000382:microbiology*; D017861:Porphyromonas / Q000187:drug effects; D011424:Propionibacterium / Q000187:drug effects; D041181:Staphylococcus hominis / Q000187:drug effects; D014678:Veillonella / Q000187:drug effects
D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D015311:Cefmetazole; D002981:Clindamycin; D002939:Ciprofloxacin; D000658:Amoxicillin; D017963:Azithromycin; D015242:Ofloxacin; D017291:Clarithromycin