Identification and antimicrobial susceptibility profile of bacteria isolated from primary endodontic infections

Author(s)

Mariano, Lorena Souza Santos ; Nakamura-Silva, Rafael ; Macedo, Luciana Martins Domingues de ; de Oliveira-Silva, Mariana ; Goulart, Rafael da Silva ; Pelisson, Marsileni ; Vespero, Eliana Carolina ; Silva-Sousa, Yara Teresinha Correa ; Pitondo-Silva, Andre

• Document type: Journal article
• Source: BRAZILIAN ORAL RESEARCH; v. 38, p. 10-pg., 2024-01-01.

Abstract

This study aimed to identify and characterize the antimicrobial susceptibility profile of bacteria found in primary endodontic infections in the teeth of patients treated at the Dental September to December 2019, samples were obtained from 21 patients with primary endodontic infections. The collections were carried out in triplicate using paper cones placed close to the total length of the root canal. Bacterial isolation was performed in Brain Heart Infusion agar, Blood agar, and other selective culture media cultured at 37 degrees C for up to 48 h under aerobiosis and microaerophilic conditions. The bacterial species were identified using the Vitek 2 automated system. The disk diffusion method on agar M & uuml;eller-Hinton was used to assess antimicrobial susceptibility with the recommended antimicrobials for each identified bacterial species. A total of 49 antibiotics were evaluated. Fifteen of the 21 samples collected showed bacterial growth, and 17 bacterial isolates were found. There were 10 different bacterial species identified: Enterococcus faecalis (four isolates), Streptococcus mitis/ oralis (three isolates), Streptococcus anginosus (three isolates) being the most common, followed by Staphylococcus epidermidis, Enterococcus cloacae, Klebsiella variicola, and Providencia rettgeri (one isolate of each species). The analysis demonstrated significant susceptibility to most of the tested antibiotics. However, some Enterococcus isolates resisted the antibiotic's erythromycin, ciprofloxacin, and tetracycline. A Staphylococcus epidermidis isolate was characterized as multidrugresistant. Five Streptococcus isolates were non-susceptible to all antibiotics tested. (AU)

• FAPESP's process: 13/22581-5 - Study of pathogenic mechanisms and correlation with antimicrobial resistance of Klebsiella pneumoniae from Brazil and other countries across five continents
• Grantee: André Pitondo da Silva
• Support Opportunities: Research Grants - Young Investigators Grants