Prevalence and Antibiotic Susceptibility Trends of Selected <i>Enterobacteriaceae</i>, <i>Enterococci</i>, and <i>Candida albicans</i> in the Subgingival Microbiota of German Periodontitis Patients: A Retrospective Surveillance Study

• Main Authors: Karin Jepsen (Author), Wolfgang Falk (Author), Friederike Brune (Author), Raluca Cosgarea (Author), Rolf Fimmers (Author), Isabelle Bekeredjian-Ding (Author), Søren Jepsen (Author)
• Format: Book
• Published: MDPI AG, 2022-03-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 10.3390/antibiotics11030385; 2079-6382
• Keywords: antibiotics; antibiotic resistance; candida; <i>Enterobacteria</i>; <i>Enterococci</i>; <i>Klebsiella</i>; Therapeutics. Pharmacology; RM1-950
• Source: Antibiotics, Vol 11, Iss 3, p 385 (2022)

The periodontal microbiota is ecologically diverse and may facilitate colonization by bacteria of enteric origin (<i>Enterobacteriaceae</i>, <i>Enterococci</i>) and co-infections with <i>Candida albicans</i>, possibly producing subgingival biofilms with high antimicrobial tolerance. This retrospective surveillance study followed periodontitis-associated superinfection profiles in a large patient sample. From 2008 to 2015, biofilm samples from deep periodontal pockets were collected from a total of 16,612 German adults diagnosed with periodontitis. The presence of selected <i>Enterobacteriaceae</i>, <i>Enterococci</i>, and <i>Candida albicans</i> was confirmed in overnight cultures. Antimicrobial susceptibility of these clinical isolates was tested by disk diffusion with antibiotics routinely used for treatment of oral infections, e.g., amoxicillin (AML), amoxicillin/clavulanic acid (AMC), doxycycline (DO), and ciprofloxacin (CIP). The mean annual prevalence of patients harboring <i>Enterobacteriaceae</i> in periodontal plaques was 11.5% in total and ranged from 2.5% for <i>Enterobacter cloacae</i> to 3.6% for <i>Klebsiella oxytoca</i>, 1.1% for <i>Klebsiella pneumoniae</i>, 2.8% for <i>Serratia marcescens</i>, and 1.5% for <i>Serratia liquefaciens</i>. In comparison, the mean detection rates for microbiota typically found in the oral cavity were higher, e.g., 5.6% for <i>Enterococcus</i> spp. and 21.8% for <i>Candida albicans</i>. Among the <i>Enterobacteriaceae</i>, species harboring intrinsic resistance to AML (<i>Enterobacter</i> spp., <i>Klebsiella</i> spp., <i>Serratia</i> spp.) were predominant. Non-susceptibility to AMC was observed for <i>Serratia</i> spp. and <i>Enterobacter cloacae</i>. By contrast, <i>Enterococcus</i> spp. only showed non-susceptibility to DO and CIP. Trends for increasing resistance were found to AML in <i>Serratia liquefaciens</i> and to DO in <i>Enterococcus</i> spp. Trend analysis showed decreasing resistance to AMC in <i>Serratia liquefaciens</i> and <i>Klebsiella oxytoca</i>; and to DO in <i>Serratia marcescens, liquefaciens</i>, and <i>Enterobacter cloacae</i>. This study confirms the low but consistent presence of <i>Enterobacteriaceae</i> and <i>Enterococci</i> among the subgingival microbiota recovered from periodontitis specimen. Although their pathogenetic role in periodontal lesions remains unclear, their presence in the oral cavity should be recognized as a potential reservoir for development and spread of antibiotic resistance in light of antibiotic usage in oral infections.