(0323) Patterns of Antimicrobial Resistance in Head and Neck Abscesses of Odontogenic Origin

Introduction: A vast majority of abscesses in the head and neck region are of odontogenic origin, but the patterns of antibiotic resistance in these infections have not been well defined. In order to develop an appropriate treatment algorithm for these potentially life-threatening infections, we aimed to characterize the most common pathogens and their respective rates of resistance to antibiotics reported in current primary literature.

Methods: We conducted a systematic review of the literature in accordance with PRISMA guidelines. We identified studies conducted between 1985 and 2021 reported in PubMed, Embase, and Web of Science databases. Observational studies and randomized control trials that reported bacterial isolates from head and neck abscesses of odontogenic origin and their antimicrobial resistance patterns were included. A pooled analysis was conducted.

Results: Of the 3,237 studies screened for review, 23 met the inclusion criteria with a total of 6,263 bacterial isolates. The most commonly identified organisms were alpha hemolytic Streptococcus spp. (45.2%, n = 6,263), milleri group Streptococcus spp. (25.4%, n = 173), Staphylococcus spp. (12.7%, n = 6,263), gamma hemolytic Streptococcus spp. (12.6%, n = 4,991), Prevotella (7.3%, n = 5,557), and Bacteroides (7.1%, n = 4,216). Staphylococcus had high rates of resistance to penicillin (56.9%, n = 311), amoxicillin (37.5%, n = 24), erythromycin (25%, n = 80), and amoxicillin/clavulanate (14.4%, n = 104). Streptococcus had high rates of resistance to penicillin (45.1%, n = 1,825) and amoxicillin/clavulanate (37.5%, n = 1,203), but showed no resistance to erythromycin (0%, n = 1,203) and clindamycin (0%, n = 65).

Conclusions: This study shows that Staphylococcus spp. and Streptococcus spp., with high rates of resistance to penicillin and amoxicillin, are often implicated in head and neck abscesses of odontogenic origin. Given the potential of these infections to cause serious complications, future treatment guidelines should take into account these microbiologic patterns.