Vol.53 No.8 August 2005

Detection of β-lactams resistant anaerobic bacteria from human saliva

Satoshi Kinoshita¹⁾, Rie Iwai¹⁾, Yasuhiro Matsumoto¹⁾, Takeo Maeda¹⁾, Kazushi Yoshikawa²⁾, Kazuhiro Matsumoto¹⁾, Makoto Tabushi¹⁾, Yuichi Murata¹⁾, Yutaka Shinoda¹⁾, Tomio Iseki¹⁾, Takatoshi Onoe³⁾ and Shosuke Morita¹⁾

¹⁾First Department of Oral and Maxillofacial Surgery, Osaka Dental University,
8-1 Kuzuhahanazono-cho, Hirakata, Osaka, Japan
²⁾Department of Operative Dentistry, Osaka Dental University
³⁾Faculty of Human Studies, Taisei Gakuin University

Abstract

We examined the β-lactams-resistant bacteria in human saliva. Saliva was gathered from adult men at rest and dropped on to agar plates containing ampicillin (ABPC), cefaclor (CCL), or cefteram (CFTM). Colony, growing anaerobic cultured and drug-selected bacteria were examined for identification, β-lactamase productivity, and ABPC, cefazoline (CEZ), CCL, and CFTM MICs. In 12 cases, ABPC, CCL, or CFTM-selected bacteria were gathered for 39, 45, or 46 strains, and β-lactamase producers were 21, 2, or 3 strains each. Facultative anaerobic Gram-positive rods were the most frequent bacteria in ABPC selected, followed by obligate anaerobic Gram-negative rods. Facultative anaerobic Gram-positive cocci were the most frequent bacteria followed by facultative anaerobic Gram-negative rods in CCL selected. Facultative anaerobic Gram-positive rods were the most frequent, followed by facultative anaerobic Gram-negative cocci in CFTM selected. MIC₈₀ of each of the 4 drugs against ABPC or CFTM-selected bacteria were distributed from 64 to > 256 μg/mL, and ABPC was 16 μg/mL and the remaining 3 drugs were 256 μg/mL against CCL selected. β-Lactamase producers, and penicillins and cephems-resistant strains were selected by ABPC, β-lactamase nonproducers, and cephems-resistant strains were selected by CCL, and β-lactamase nonproducers, and penicillins and cephems-resistant strains were selected by CFTM. When we select the drug-resistant bacteria using by drugs, we have to take care that, various bacterial species, resistant trend, and resistant mechanism, caused by using various drugs.

Key word

oral bacterial flora, β-lactams, β-lactams resistance, antibiotic selected strain

Received

July 4, 2005

Accepted

July 27, 2005

Jpn. J. Chemother. 53 (8): 471-475, 2005