Extended-spectrum beta-lactamase-producing bacteria are not detected in supragingival plaque samples from human fecal carriers of ESBL-producing Enterobacteriaceae.

Abstract

BACKGROUND:

The prevalence of infections caused by Cefotaximase-Munich (CTX-M)-type extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) has rapidly increased during the past 15 years. Enterobacteriaceae are commonly found in the gastrointestinal tract and long-term intestinal carriage is considered important for the spread of ESBL and as a source of clinical infections. Oral biofilm such as supragingival plaque is known to contain numerous antibiotic resistance determinants and may also represent a poorly investigated site for ESBL carriage and further spread.

OBJECTIVE:

To investigate possible carriage of ESBL-producing bacteria in supragingival plaque of known fecal carriers of these bacteria.

DESIGN:

We screened for the presence of aerobic and anaerobic ESBL-producing bacteria and bla CTX-M in supragingival plaque samples from healthy human adults with culture-verified fecal carriage of CTX-M-producing Escherichia coli. The presence or absence of Enterobacteriaceae and ESBL-producing bacteria in plaque samples was evaluated using culture-based methods and consensus CTX-M PCR.

RESULTS:

Oral samples were obtained from 17 participants with known previous carriage of ESBL-producing E. coli. No ESBL-producing bacteria or ESBL genes were detected using culture-based and molecular methods. One colony of Rahnella aquatilis harboring the class A ESBL gene bla RAHN-1/2 was identified in an oral sample from one of the participants.

CONCLUSION:

This pilot study supports the notion that the presence of CTX-M-producing bacteria is uncommon in oral plaque of healthy human adult fecal carriers. Due to the limited number of persons tested, a low prevalence of oral ESBL-carriage in healthy adults or carriage in selected groups of patients cannot be excluded. To our knowledge, this is the first description of an R. aquatilis with the RAHN-1/2 gene in the oral cavity.

• Authors: Arne Søraas, Ingar Olsen, Arnfinn Sundsfjord, Trude Handal, Ola Bjørang, Pål Arne Jenum
• Journal: Journal of oral microbiology (J Oral Microbiol) Vol. 6 ( 2014) ISSN: 2000-2297 [Print] United States
• PMID: 25206941 (Publication Type: Journal Article)