Trends in the prevalence and antibiotic susceptibility of anaerobic Gram-negative bacteria causing clinical infections in Estonia

Objective: The aim of our study was to describe the species distribution and changes in resistance profile anaerobic bacteria isolated at Tartu University Hospital. Methods: data for 2010, 2016 2020 were analysed retrospectively. strains identified by Vitek2 (2010) MALDI-TOF MS (2016, 2020); MIC values antibiotics determined using gradient tests. Resistance interpreted EUCAST breakpoints. Results: average number cultures received during 10 years increased from 1551 5983; (386%).. most common pathogens Gram negative rod-shaped (Bacteroides fragilis, Bacteroides spp., Fusobacterium spp. Prevotella spp.). percentage susceptible three studied stable majority drug-bug combinations tested, except beta-lactam antibiotic sensitivity imipenem ampicillin-sulbactam, penicillin). There significant differences (p < 0.05) when comparing with 2016. higher among Bacterioides Bacteriodes fragilis imipenem, ampicillin-sulbactam clindamycin than same observed vs 2010 metronidazole, penicillin cefoxitin. In contrast, surprisingly lower other Gram-negative rods. Conclusions: no shift spectrum microbial groups as causative agents clinical infections 2010-2020 period. However, due improvement identification methods, increased. pattern anaerobes stable, but may indicate a further steady increase resistance. surveillance is important predict efficiency empirical treatment.