Antibiotic susceptibility patterns of gram-negative anaerobic bacteria isolated from clinical samples

Aim:Although anaerobic bacteria are the normal flora of the body, they can cause infection with the weakening of the immune system.Isolation and identification of these bacteria are difficult and not performed in most laboratories.For this reason, anaerobic bacteria can often be ignored.As a result, antibiotic resistance situations that develop cannot be detected.We carried out this study to reveal that anaerobic bacteria are important, that knowing antibiotic resistance profiles is necessary for the courseof treatment, and that antibiotic susceptibility tests should be performed at certain periods.Material and Method:Between 11.06.2019 -04.03.2020 dates,Dicle University Faculty of Medicine Medical Microbiology Department to the Bacteriology / Culture laboratory 372 samples were sent with the request of anaerobe culture from various clinical units.These samples were first inoculated on Brucellablood agar for bacteria isolation.After identifying the isolated bacteria with MALDI-TOF MS, the E-test method was used to determine the antimicrobial susceptibility profiles.Results:Antibiotics with the highest antimicrobial resistance were determined as 100% penicillin (P), 41.2% clindamycin (CM) and 35.3% amoxicillin-clavulanic acid (AMC), respectively in 17 isolated Bacterioidesspecies.Antibiotics with the highest antimicrobial resistance in the 22 isolated Prevotellaspecies were determined as 45.5% penicillin (P) and 27.3% moxifloxacin (MX).Again, only metronidazole (MZ) resistance was observed in 1 Dialister pneumosintesbacteria, whereas resistance was observed against penicillin (P), imipenem (IP) and piperacillin-tazobactam (TPZ) antibiotics in 1 Veillonella parvulabacteria.Finally, resistance was observed against any antibiotic in 4 Fusobacteriumspecies isolated.Conclusion:It was observed that the majority of the Gram-negativeanaerobic bacteria isolated in our study developed resistance to penicillin, clindamycin, moxifloxacin, metronidazole and amoxicillin-clavulanic acid, or had an increased resistance to these antibiotics, and were also sensitive to the remaining antibiotics.