Prevalence and Antibiogram of Rothia mucilaginosa and Staphylococcus spp Isolated from Oral Cavity of Students in a Tertiary Institution

Abstract

Bacteremia and systemic infection caused by Rothia mucilaginosa and Staphylococcus spp are uncommon and their resistance to antibiotics are becoming overwhelming. Hence, this study was carried out to investigate the prevalence and antibiogram of Rothia mucilaginosa and Staphylococcus spp from oral cavity of students in a Tertiary Institution. A total of fifty (50) specimen were collected from the oral cavity of male and female students in Rivers State University and subjected to standard microbiological procedures such as culturing, isolation, identification as well as antibiotic susceptibility test. Sixty-seven (67) bacterial isolates were identified with Staphylococcus aureus 43(64.2%) occurring most, followed by  Rothia  mucilaginosa 18(26.7%) and Staphylococcus  epidermidis 6(8.9%). All the isolates of Rothia mucilaginosa, Staphylococcus aureus and Staphylococcus epidermidis were positive for the presence of haemolysin and catalase enzymes. The results of the percentage occurrence among male and female students revealed that Staphylococcus aureus had the highest occurrence (64.18%:59.38%) followed closely by Rothia mucilaginosa (22.86%:31.25%) while Staphylococcus epidermidis had the least prevalence (8.95%:9.37%) in male and female respectively. The result of the susceptibility patterns showed that majority of Staphylococcus aureus, Staphylococcus epidermidis and Rothia mucilaginosa were highly sensitive to ciprofloxacin (90.70%; 100%; 83.33%) and gentamicin (76.74%; 83.33%: 100%), and highly resistant to azithromycin (44.19% and 66.67%) for Staphylococcus aureus, Staphylococcus epidermidis and Rothia mucilaginosa were highly resistant to ampiclox (61.11%). The results of multiple antibiotic resistance (MAR) indices, showed that 86.05% of S. aureus;  83.33% of R. mucilaginosa and 100% of S. epidermidis had MAR indices ≥ 0.2. This study displays serious threat to public health because these microorganisms which showed some virulent factors such as production of haemolysin and catalase enzymes may cause life threatening infections in immunocompromised persons. The indiscriminate use of antibiotics to prevent increased antimicrobial resistance is advocated.