Odontogenic Infections - Regional Differences in Antibiotic Resistance

Objectives: Odontogenic infections and antibiotic resistance of their pathogens play an important role in maxillofacial surgery. A retrospective study was conducted to determine the pathogen spectrum of odontogenic infections and the antibiotic resistance of infecting pathogens. A prospective study from Halle, Germany, was used as a comparator to examine for potential regional differences.
Methods: The data of 178 patients who received inpatient or outpatient treatment for odontogenic abscess and had a pathogen identified from abscess specimen from 1/2014 - 12/2016 at the Clinic for Oral and Maxillofacial Surgery at Klinikum Rechts der Isar in Munich, Germany, were analysed. Resistance tests were available for 135 of the 565 germs isolated. The pathogen spectrum and antibiotic resistance rates were examined and compared with findings from Halle.
Results: In 178 patients 565 germs were isolated of which the majority (n=383) was aerobic; 182 pathogens were anaerobic. The average bacterial count per infection was 3.17. The most frequent aerobic, gram-positive pathogens were of the species Streptococcus (56.2%) and Staphylococcus (28.3%). Haemophilus was the most frequent in the group of aerobic, gram-negative germs (33.0%). For anaerobic pathogens, Parvimonas predominated the gram-positive group (55.8%) and Prevotella the gram-negative group (74%).
The highest resistance rates were observed for clindamycin (18.6%) and penicillin G/V (11.5%). Other resistance rates were relatively low: 6.8% (amoxicillin/clavulanic acid), 3.7% (imipinem) and 8.7% (piperacillin/tazobactam).
Resistance rates in Halle were similar: 11.9% (clindamycin), 9.0% (penicillin G/V), 2.8% (amoxicillin/clavulanic acid), 1.1% (imipinem) and 1.3% (piperacillin/tazobactam). The somewhat higher rates in Munich can best be attributed to the different types of studies.
Conclusions: There were no significant differences in the pathogen spectrum or antibiotic resistance between the two cities. Therefore, a recommendation for regional adaptation of antibiotics could not be derived.