Related Experiment Video
Updated: Jun 2, 2026
07:15
Robust Ligature-Induced Model of Murine Periodontitis for the Evaluation of Oral Neutrophils
Published on: January 21, 2020
Spiramycin resistance in human periodontitis microbiota.
Thomas E Rams1, Sebastien Dujardin, Jacqueline D Sautter
1Department of Periodontology and Oral Implantology, Oral Microbiology Testing Service Laboratory, Temple University School of Dentistry, Philadelphia, PA 19140, USA. trams@temple.edu
Anaerobe
|April 29, 2011
Summary
Antibiotic resistance in periodontal pathogens is common, with nearly half of severe periodontitis patients showing resistance to spiramycin. Combined spiramycin and metronidazole show potential for treating periodontitis, especially for patients allergic to amoxicillin.
Area of Science:
- Periodontology
- Microbiology
- Infectious Diseases
Background:
- Periodontal disease is a chronic inflammatory condition affecting the gums and supporting bone.
- Antibiotic therapy is often used to manage severe periodontitis by targeting causative bacteria.
- Understanding antibiotic resistance patterns is crucial for effective treatment strategies.
Purpose of the Study:
- To determine the in vitro resistance of key periodontal pathogens to spiramycin, amoxicillin, and metronidazole.
- To assess resistance in pathogens isolated from patients with severe periodontitis in the United States.
- To evaluate potential synergistic or alternative antibiotic combinations for periodontitis treatment.
Main Methods:
- Subgingival plaque samples were collected from 37 adults with severe periodontitis.
- Putative periodontal pathogens were isolated and identified using anaerobic culturing.
- In vitro antibiotic resistance was tested against spiramycin (4 μg/ml), amoxicillin (8 μg/ml), and metronidazole (16 μg/ml).
Main Results:
- Spiramycin resistance was observed in 48.7% of subjects, amoxicillin resistance in 62.2%, and metronidazole resistance in 27.0%.
- Fusobacterium nucleatum showed high resistance to spiramycin (44.4%), while Prevotella intermedia/nigrescens showed high resistance to amoxicillin (55.5%).
- Streptococcus constellatus and Streptococcus intermedius exhibited the highest resistance to metronidazole (70% and 40%, respectively).
Conclusions:
- In vitro resistance to spiramycin is prevalent in periodontal pathogens from US patients, particularly Fusobacterium nucleatum.
- Combined spiramycin and metronidazole demonstrated potential antimicrobial efficacy, comparable to amoxicillin and metronidazole.
- This combination could be a viable alternative for periodontitis treatment in patients with amoxicillin hypersensitivity.
Related Concept Videos
01:27The Oral Microbiota
The oral microbiome includes a complex ecosystem comprising over 700 microbial species, identified through genomic sequencing and culture-based analyses to date. This community includes a core microbiome, found universally among individuals, and a variable component influenced by environmental factors such as diet, lifestyle, and host genetics. Site-specific conditions, including oxygen gradients, pH levels, and nutrient availability, determine the spatial distribution of these microorganisms...
01:25Clinical Significance of Antibiotic Resistance
Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within the One...
01:25Mechanism of Antibiotic Resistance in MRSA
Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and acquisition...
01:21Microbiota Modulation by Antibiotics
Antibiotics have revolutionized modern medicine by saving countless lives from bacterial infections. However, their widespread use has inadvertently harmed the delicate balance of the human gut microbiota. The gut microbiota, a complex community of bacteria, archaea, viruses, and fungi, plays a vital role in regulating metabolism, immune responses, and maintaining intestinal health. Antibiotics, especially broad-spectrum types, disrupt this ecosystem by eradicating both harmful and beneficial...
01:29Microbiota of the Respiratory Tract
The human respiratory tract, comprising the upper and lower segments, serves as a critical interface with the external environment. The upper respiratory tract (URT)—including the nostrils, sinuses, pharynx, and oropharynx—is heavily colonized by microbes, while the lower respiratory tract (LRT), composed of the larynx, trachea, bronchi, and lungs, was long thought to be sterile. However, recent molecular studies have revealed that the lungs are not devoid of microbes but act more like...
01:30Development of Antibiotic Resistance
Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...