Related Experiment Video
Updated: Jan 17, 2026
Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
Published on: April 18, 2019
Spiramycin-Metronidazole Synergism Testing on Aggregatibacter actinomycetemcomitans.
Thomas E Rams1, Joanie Faucher1
1Department of Periodontology and Oral Implantology, Temple University Maurice H. Kornberg School of Dentistry, Philadelphia, USA.
The combination of spiramycin and metronidazole showed improved activity against Aggregatibacter actinomycetemcomitans compared to individual use. While synergism was observed in one case, other antibiotic combinations were more consistently effective.
Area of Science:
- Microbiology
- Pharmacology
- Infectious Diseases
Background:
- Aggregatibacter actinomycetemcomitans is a significant pathogen in periodontitis, peri-implantitis, and non-oral infections.
- Investigating synergistic antibiotic combinations is crucial for effective treatment strategies.
Purpose of the Study:
- To evaluate the in vitro synergistic potential of spiramycin-metronidazole against A. actinomycetemcomitans.
- To compare this combination with amoxicillin-metronidazole and ciprofloxacin-metronidazole.
Main Methods:
- Determined minimal inhibitory concentrations (MICs) for individual antibiotics against four A. actinomycetemcomitans clinical isolates.
- Assessed antibiotic pair synergism using gradient diffusion strips and fractional inhibitory concentration index values.
Main Results:
- Spiramycin and metronidazole showed limited individual antimicrobial activity against A. actinomycetemcomitans.
- Combined use resulted in lower MICs and reduced resistance.
- Spiramycin-metronidazole synergism was detected in one isolate; amoxicillin-metronidazole and ciprofloxacin-metronidazole showed synergism against all isolates.
Conclusions:
- Spiramycin-metronidazole combination enhances in vitro activity against A. actinomycetemcomitans.
- This study reports the first instance of spiramycin-metronidazole synergism against A. actinomycetemcomitans.
- Amoxicillin-metronidazole and ciprofloxacin-metronidazole demonstrated more frequent synergism against A. actinomycetemcomitans.
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
07:51High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method
Published on: May 21, 2018
