Comparison of the phenotypic profile of antimicrobial resistance in the oral microbiota of non-smokers, tobacco smokers, and electronic cigarette vapers - A pilot study

Introduction: The microbiota is a community of microorganisms that live in a specific environment. Their type and number depend on multiple internal and external factors. Oral is the second most diverse and populated microbiota of the body. Smoking and vaping induce changes in its composition, and it has been demonstrated that they can lead to an increase in antimicrobial resistance. Objective: To compare the phenotypic profile of antimicrobial resistance in the oral microbiota of non-smokers, tobacco users, and electronic cigarette vapers. Methods: An observational, descriptive, cross-sectional, and comparative study was carried out. Three groups of non-smokers, smokers of conventional tobacco, and electronic cigarette (EC) vapers of tobacco flavored e-juice were formed. Oral cavity samples were obtained, incubated, and seeded in agar plates. Bacteria were isolated and identified performing Gram staining, oxidase, indole, and biochemical test panels. Susceptibility tests were performed using a MicroScan autoSCAN-4 system and the Kirby–Bauer test. Results: Variation was observed in the populations of bacteria that were isolated in each of the groups, but the non-smokers showed the most pathogens. In the non-smoking group, Staphylococcus sciuri was the most common bacteria, Staphylococcus sciuri and Enterobacter cloacae were the most abundant in the smoking group, and in the EC vapers group, the most common bacteria were Staphylococcus epidermidis and Staphylococcus sciuri. Conclusion: Multidrug resistance was observed in all the groups. However, EC vapers showed the highest proportions of antimicrobial resistance, raising a major concern.