Occurrence and antimicrobial susceptibility of enteric rods and pseudomonads isolated from the dental prostheses biofilm

• Published in: Journal of applied oral science 2016-09, Vol.24 (5), p.462-471
• Main Authors: Silva, Sanrrangers Sales, Ribeiro, Maximilo de Oliveira, Gomes, Francisco Isaac Fernandes, Chaves, Hellíada Vasconcelos, Silva, Antonio Alfredo Rodrigues E, Zanin, Iriana Carla Junqueira, Barbosa, Francisco Cesar Barroso
• Format: Article
• Language: English
• Subjects: Adult; Age Distribution; Aged; Aged, 80 and over; Anti-Bacterial Agents - pharmacology; Biofilms; Biofilms - growth & development; Dental Prosthesis - microbiology; DENTISTRY, ORAL SURGERY & MEDICINE; Drug resistance; Drug Resistance, Multiple, Bacterial; Enterobacteriaceae; Enterobacteriaceae - drug effects; Enterobacteriaceae - isolation & purification; Female; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Original; Pseudomonas; Pseudomonas - drug effects; Pseudomonas - isolation & purification; Reference Values; Sex Distribution; Statistics, Nonparametric; Time Factors
• ISSN: 1678-7757; 1678-7765; 1678-7765; 1678-7757
• DOI: 10.1590/1678-775720160032

To determine the occurrence and the in vitro antimicrobial susceptibility of enteric rods and pseudomonads from the denture biofilm of 52 subjects at the Center for Dental Specialties of Sobral/ Ceara, Brazil. Denture biofilm was collected and samples plated on MacConkey agar. The isolated bacterial colonies were identified using the BBL Crystal enteric/non-fermenter system. Antibiotic bacterial susceptibility was assessed by the disc diffusion method of amoxicillin, amoxicillin/clavulanic acid, doxycycline, tetracycline, tobramycin, imipenem, cefotaxime, and ciprofloxacin. The Minimum Inhibitory Concentration (MIC) of cefotaxime, tobramycin, doxycycline, imipenem, and ciprofloxacin was determined for 40 species by E-test. 34 subjects (65.4%) harbored enteric rods in their prostheses. Klebsiella pneumoniae (26.5%), Escherichia coli (23.5%), and Enterobacter aerogenes (23.5%) were the most prevalent species. All organisms were susceptible to ciprofloxacin and most species were resistant to amoxicillin or amoxicillin/clavulanic acid, demonstrating variable sensitivity patterns to other antimicrobials. However, the MIC showed the emergence of strains with reduced sensitivity to ciprofloxacin (MIC90≥3 μg/ mL) and cefotaxime (MIC90≥2 μg/mL). The findings show high prevalence of nosocomial diseases-related bacterial species and low susceptibility to antimicrobial drugs. Therefore, these results imply caution against the indiscriminate use of broad spectrum antibiotics in dental practice.