Related Experiment Video
Updated: Sep 27, 2025
Examination of Host Phenotypes in Gambusia affinis Following Antibiotic Treatment
Published on: February 22, 2017
Antimicrobial susceptibility testing is crucial when treating Finegoldia magna infections
Fabienne Walser1, Julia Prinz1,2, Stefan Rahm3
1Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Raemistrasse 100, CH-8091, Zurich, Switzerland.
Abstract:
Finegoldia magna is an anaerobic gram-positive bacterium that can cause invasive human infections. Recently, a 52-year-old patient suffering from a periprosthetic joint infection (PJI) due to F. magna was treated with cefepime on hemodialysis; however, treatment failed due to relapse caused by antibiotic-resistant strains. Reports on the antimicrobial susceptibility of F. magna clinical isolates are rare. We collected 57 clinical F. magna isolates from Zurich, Switzerland, between September 2019 and July 2020 and tested their antimicrobial susceptibility to investigate the local resistance pattern. Antimicrobial susceptibility testing (AST) was evaluated for nine antibiotics (benzylpenicillin, amoxicillin/clavulanic acid, cefuroxime, cefepime, levofloxacin, rifampicin, metronidazole, doxycycline, and clindamycin) by E-test according to CLSI guidelines. All F. magna strains were susceptible to benzylpenicillin, amoxicillin/clavulanic acid, and metronidazole, while 75% to clindamycin. F. magna isolates showed MIC values lower than species-unrelated breakpoints for cefuroxime, levofloxacin, and cefepime in 93%, 56%, and 32% of the cases, respectively. MIC values for rifampicin and doxycycline were lower than locally determined ECOFFs in 98% and 72% of the cases, respectively. In summary, we recommend the use of benzylpenicillin, amoxicillin/clavulanic acid, or metronidazole without prior AST as first-line treatment option against F. magna PJI infections. If cefuroxime, cefepime, levofloxacin, rifampicin, doxycycline, or clindamycin are used, AST is mandatory.
Insights
Finegoldia magna infections can be challenging due to antibiotic resistance. Benzylpenicillin, amoxicillin/clavulanic acid, and metronidazole are recommended first-line treatments, while other antibiotics require susceptibility testing.
Area of Science:
- Medical Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Finegoldia magna is an anaerobic gram-positive bacterium implicated in invasive human infections.
- Periprosthetic joint infections (PJI) caused by F. magna can be difficult to treat, with antibiotic resistance posing a significant challenge.
- Limited data exists on the antimicrobial susceptibility patterns of F. magna clinical isolates.
Purpose of the Study:
- To investigate the local antimicrobial resistance patterns of clinical Finegoldia magna isolates.
- To guide appropriate antibiotic selection for F. magna infections, particularly PJIs.
Main Methods:
- Collected 57 clinical F. magna isolates from Zurich, Switzerland (September 2019 - July 2020).
- Performed antimicrobial susceptibility testing (AST) using E-test according to CLSI guidelines for nine antibiotics.
- Evaluated minimum inhibitory concentration (MIC) values against species-unrelated breakpoints and epidemiological cutoff values (ECOFFs).
Main Results:
- All isolates were susceptible to benzylpenicillin, amoxicillin/clavulanic acid, and metronidazole.
- High susceptibility rates were observed for benzylpenicillin (100%), amoxicillin/clavulanic acid (100%), and metronidazole (100%).
- Susceptibility varied for other agents: clindamycin (75%), cefuroxime (93%), levofloxacin (56%), cefepime (32%), rifampicin (98%), and doxycycline (72%).
Conclusions:
- Benzylpenicillin, amoxicillin/clavulanic acid, or metronidazole are recommended as first-line empirical treatments for F. magna PJI.
- Antimicrobial susceptibility testing is mandatory for cefuroxime, cefepime, levofloxacin, rifampicin, doxycycline, and clindamycin due to variable resistance.
- Understanding local resistance patterns is crucial for effective management of F. magna infections.
More Related Videos
08:04Quantitative Examination of Antibiotic Susceptibility of Neisseria gonorrhoeae Aggregates Using ATP-utilization Commercial Assays and Live/Dead Staining
Published on: February 8, 2019
12:03Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
Published on: April 18, 2019