Trends and Impact in Antimicrobial Resistance Among Bacteroides and Parabacteroides Species in 2007–2012 Compared to 2013–2017

Abstract

The aim of this study was to analyze the susceptibility of Bacteroides and Parabacteroides spp. strains, isolated from patients hospitalized in the clinical hospital in Poland to penicillin, amoxicillin with clavulanic acid, imipenem, clindamycin, and metronidazole. Methods: We analyzed susceptibility of 476 isolates to routinely use for the treatment of anaerobic bacterial infections antibiotics. E test method was used to determining the minimal inhibitory concentration values. To show the trend of drug resistance, we compared data from two periods within the years 2003-2017. Results: Research results indicate that the problem of resistance is mainly related to strains belonging to nonfragilis Bacteroides. In the analyzed periods, there was an increase in the percentage of clindamycin-resistant isolates (35.21% vs. 53.33%), amoxicillin/clavulanic acid (2.83% vs. 8.15%), and imipenem (1.41% vs. 3.7%). In isolates belonging to Parabacteroides distasonis, we observed a constant high (*50%) percentage of clindamycin-resistant strains. The overwhelming majority of B. fragilis strains were resistant to penicillin (>95%) and about 20% of the isolates were not susceptible to clindamycin. Conclusions: Clindamycin, due to the high and increasing percentage of resistant strains, may not be a good choice in the empirical therapy of infections caused by Bacteroides and P. distasonis. Our study highlighted the importance of a routine or at least periodic monitoring of antimicrobial susceptibility of anaerobic Gramnegative bacilli, providing important information for appropriate therapy. The study shows that infection caused (or suspected of being caused) by Bacteroides and Parabacteroides spp. can be empirically treated with metronidazole or imipenem.

The Role of the Bacteroides spp. in Bacteraemia

“…Similar results are presented by other researchers [30,57,63]. Increasing resistance to clindamycin is observed in Europe [17,42] including Poland [26]. The results were confirmed in study covering 8 medical centres.…”

Parabacteroides distasonis: intriguing aerotolerant gut anaerobe with emerging antimicrobial resistance and pathogenic and probiotic roles in human health

“…76 This suggests that a growing proportion of P. distasonis strains have reduced susceptibility to clindamycin. 62 It is possible that the indiscriminate use of this antibiotic in clinical settings, especially for members of the Bacteroides and Parabacteroides genera, exerts selective pressure, leading to increased resistance of P. distasonis to clindamycin over time. 77 One of the potential underlying mechanisms for clindamycin resistance in P. distasonis is the presence of the resistance gene ermF, known to be frequently found in various anaerobes.…”

“…and Parabacteroides spp. are becoming increasingly more resistant to certain antibiotics 62 because of an increase in the number of antimicrobial resistance-related virulence genes. Within the genus Parabacteroides, P. distasonis has a wide spectrum of resistance to various beta-lactams, being particularly resistant to the penicillin class.…”

“… 76 This suggests that a growing proportion of P. distasonis strains have reduced susceptibility to clindamycin. 62 It is possible that the indiscriminate use of this antibiotic in clinical settings, especially for members of the Bacteroides and Parabacteroides genera, exerts selective pressure, leading to increased resistance of P. distasonis to clindamycin over time. 77 …”

Antimicrobial Susceptibility of Clinical Oral Isolates of Actinomyces spp.

“…Though MDR is uncommon among the Actinomyces, this is an increasing problem for other anaerobic bacteria. The literature refers to Bacteroides fragilis isolates with resistance to penicillin, piperacillin-tazobactam, meropenem, clindamycin and metronidazole [35][36][37][38]. Clostridioides difficile showed MDR for moxifloxacin, clindamycin, erythromycin and rifampicin.…”