J Clin Pathol Qual Control.  1997 Jun;19(1):191-196.

Effect on the Susceptibillities of Bacteroides fragilis Group Organisms by the Use of Wilkins-Chalgren Agar

• Shin HJ
• Xu XS
• Lee J
• Lee K
• Chong Y
• Kwon OH

Abstract

BACKGROUND: Anaerobic bacteria are increasingly being recognized as clinically significant. Bacteroides fragilis group (BFG) organisms are the most frequently isolated anaerobes. A significant increase in resistance to antimicrobial agents among these organisms has been reported in worldwide as well as in Korea. Several media and methods for susceptibility testing of anaerobes have been published. This study was to determine the effect of media on the susceptibilities of BFG organisms.
METHODS
Nonduplicate clinical isolates of 60 BFG organisms were collected during 1994 at Severance Hospital. Species identification was performed by ATB system or conventional methods. Antimicrobial susceptibility was tested by an agar dilution method using Wilkins-Chalgren agar and brucella agar supplemented with vitamin K1 and 5% laked sheep blood (BBA).
RESULTS
The MICs of all of the antimicrobial agents were slightly higher by BBA than by Wilkins-Chalgren agar. Except for metronidazole, 98% or more of the results were within two log2 dilution. However, no significant difference was noted in resistance rate.
CONCLUSIONS
Wilkins-Chalgren agar is less expensive and simpler to prepare than BBA with comparable results for the antimicrobial susceptibility testing of BFG organsims.

MeSH Terms

Agar*
Anti-Infective Agents
Bacteria, Anaerobic
Bacteroides fragilis*
Bacteroides*
Brucella
Korea
Lakes
Metronidazole
Sheep
Vitamin K 1
Agar
Anti-Infective Agents
Metronidazole
Vitamin K 1