Phenotypic Characterization and Antibiogram of Non-Oral Bacteria Isolates from Patients Attending Dental Clinic at Federal College of Dental Technology and Therapy Medical Center Enugu

Background and Objectives: Antibiotic-resistance among microbiota found within the oral cavity is a growing concern due to extensive use of antibiotics in dental practice both for therapeutic and prophylactic reasons, but has so far received little attention in recent time. The aim of this study was to determine the antibiogram of non-oral bacteria isolates from patients attending dental clinic at Federal College of Dental Technology and Therapy Medical Center Enugu (FEDCODTTEN) Methodology: A total of two hundred (200) oral swab samples were collected from patients with dental disease, placed in sterilized Brain Heart Infusion broth and immediately transported to the Microbiology Laboratory Unit of Federal College of Dental Technology and Therapy Enugu, for bacteriological analysis using standard microbiological methods for isolation and characterization. Antibiogram studies of non-oral bacteria was performed using the Kirby–Bauer disk diffusion method and the results were interpreted using the Clinical Laboratory Standard Institute (CLSI) zone diameter breakpoints. Multiple antibiotic resistance index (MARI) was determined for Multidrug Resistant (MDR) non-oral bacteria.

Results: Phenotypic characterization of non-oral bacteria revealed an occurrence rate of S. aureus

35(17.5%) followed by E. coli 18(9.0%), Salmonella typhi 16(8.0 %) and K. oxytoca 4(2.0%) as the least predominant bacteria species. Among the oral site, lower right quadrant showed increase isolation rate of 30(15.0%) bacteria followed by lower left quadrant 23(11.5%) while upper right quadrant accounted 15(7.5 %) with the least isolation rate. There was no statistically significant difference in the prevalence of non-oral bacteria in right quadrant and left quadrant samples from dental disease patients (P < 0.05). Non-oral bacteria isolate exhibited 57.1-100% resistant to Ertapenem, colisitn, amoxillicin, azetronam, colistin, ampicillin and clindamycin with Multiple Antibiotic Resistant Index (MARI) ranged from 0.4-0.7, indicating high level of multi-drug resistance but were susceptible to ciprofloxacin 77.8%, gentamicin 100% and imipenem 100%.

Conclusion: The high antibiotic resistant and increase multi-drug resistance outcome reported among non-oral bacteria in this study calls for strengthened efforts in antibiotic stewardship and infection prevention and control measures in dental practices with the need to implement regular awareness programs at time interval to control and manage multi-drug resistance bacteria through judicious use of antibiotic to re-establish dominance over multi-drug resistance non-oral bacteria implicated in dental diseases.