Bacterial Profile and Antibiotic Resistance in Oral and Maxillofacial Infections.

Background/

Objectives

Oral and maxillofacial infections present polybacterial profiles, including both aerobic and anaerobic bacteria. Increasing antibiotic resistance poses a significant challenge to pharmacological treatment of these infections. The aim of this study was to present a bacterial profile and assess antibiotic resistance found in these infections.

Methods

This retrospective analysis is based on medical records of 224 patients affected with maxillofacial infections. Microbiological cultures and antibiotic susceptibility testing were performed for all patients.

Results

In 78.57% of the patients, a positive microbiological culture was obtained. A total of 72.72% of culture-positive patients showed multi-bacterial cultures (128/176). Predominant bacteria included Streptococcus, detected in 156 cases (39%), followed by Staphylococcus, found in 64 cases (16%), and Prevotella, detected in 56 of 400 total bacterial isolates (14%). The most often isolated aerobic strains were Streptococcus mitis/oralis detected in 64 (16%) cases and Staphylococcus epidermidis detected in 48 cases (12%), while the most common anaerobic strains were Prevotella buccae detected in 14 cases (3.5%). Streptococcus and Staphylococcus exhibited the greatest resistance to clindamycin, accounting for 51.74% and 47.63%, respectively. Aerobic Gram-positive cocci were more resistant to penicillin and amoxicillin than to cephalosporins. Among obligate anaerobes, the lowest antibiotic resistance seen was to metronidazole. The obligate anaerobes except Prevotella were sensitive to clindamycin.

Conclusions

A high rate of clindamycin resistance among aerobic and facultatively anaerobic Gram-positive cocci indicates the need to reassess the use of clindamycin in empirical therapy. The bacterial composition of infections suggests the need to use combined antibiotic therapy. First- and second-generation cephalosporins may be an effective alternative to penicillin and its derivatives.