PREVALENCE OF STAPHYLOCOCCUS AUREUS IN DENTAL INFECTIONS AND THE OCCURRENCE OF MRSA IN ISOLATES

Objectives: Staphylococcus aureus is an opportunist that causes systemic infections and dental infections in the human being body. This organism increases its resistance to many categories of antibiotics all day and turn out to be more resistant, and this led to a growing feeling of concern in this era. Given this fact, the aims of this study were to determine the frequency of S. aureus in oral infections and to determine the prevalence of MRSA strains and the sensitivity of isolated S. aureus to antibiotics, in patients who attended dental clinics in major public hospitals and private clinics in the city of Sana'a-Yemen. Subjects and methods: The study was conducted for a year, early in December 2018 and ending in November 2019. The study included 296 patients, 153 male and 143 female, ages 5 to 65, with an average age of 36.2 years. Demographic and clinical data were collected in questionnaire, then pus or oral swabs were collected from patients, cultivated, isolated and identified by standard laboratory techniques. MRSA was ascertained by means of the method of disc diffusion to 1μg of oxicillin disc and 5 μg of methacillin disc; an antimicrobial sensitivity test was carried out by disc diffusion method of selected antibiotics.The oral infections include dental abscesses, periodontal abscesses, gingivitis, periodentitis, dental caries, pulpitis and oral thrush. Results: Of a total of 296 cultured pus and swabs, only 217 produced a positive culture (73.3%). Gram-positive bacteria formed 67.4% of the total isolates where S. aureus was the predominant pathogen (43.1%). The prevalence of MRSA was 23.5%. There was a higher rate of antibiotic resistance tested in MRSA isolates compared to a lower rate of resistance in MSSA as well as 22.2% of MRSA isolates were vancomycin resistant, while only 11.4% of MSSA were vancomycin resistant. Conclusion: It can be concluded, S. aureus was the most widespread isolate in dental infections, high rate of MRSA, the appearance of S. aureus isolates resistant to vancomycin and other broad choice of antibiotics have raised MRSA in oral infections into a multi-drug-resistant, making it more and more hazardous in oral infections. Consistent assessment of oral associated infections and observing the pattern of antibiotic sensitivity and strict drug policy for antibiotics are recommended.