Determination of antimicrobial susceptibilities of clinically isolated anaerobic bacteria by E-test, ATB-ANA and agar dilution

• Published in: Anaerobe Vol. 14; no. 3; pp. 161 - 165
• Main Authors: Koru, Ozgur, Ozyurt, Mustafa
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.06.2008
• Subjects: Agar; Agar dilution; Anaerobic bacteria; Anti-Bacterial Agents - pharmacology; Antimicrobial susceptibility; ATB-ANA; Bacteria, Anaerobic - classification; Bacteria, Anaerobic - drug effects; Bacteria, Anaerobic - isolation & purification; Bacterial Infections - microbiology; Culture Media; E-test; Humans; Microbial Sensitivity Tests - methods; Reference Standards; Anaerobic bacteria; Antimicrobial susceptibility; E-test; ATB-ANA; Agar dilution
• ISSN: 1075-9964; 1095-8274
• DOI: 10.1016/j.anaerobe.2008.02.004

A total of 60 anaerobic strains were isolated from 322 clinical specimens. These isolates were tested for susceptibility to seven antibiotics (penicillin G, amoxicillin/clavulanic acid, cefoxitin, imipenem, chloramphenicol, metronidazole, clindamycin) by using ATB-ANA and Epsilometer test (E-test) strips and the results were compared with the gold standard agar dilution method. Imipenem was found as the most effective agent in vitro among the agents tested (100%). Susceptibility to penicillin G, amoxicillin/clavulanic acid, cefoxitin, chloramphenicol, metronidazole and clindamycin are 36.7%, 83.3%, 88.3%, 96.6%, 85% and 90%, respectively. E-test has showed a good correlation ( r=0.62, p=0.001) statistically with the results of agar dilution (total agreement for all antibiotics changing between 90.01% and 98.45%) and a moderate correlation ( r=0.45, p=0.048) with the results of ATB-ANA method (total agreement for all antibiotics changing between 75.46% and 98.76%). However, the routine use of agar dilution procedure is concluded to be cumbersome, whereas E-test method offers a reliable alternative.