From the Guidelines
Prevotella is indeed an important pathogen in human disease, as it is frequently implicated in polymicrobial infections, particularly abscesses, periodontal disease, and infections of the respiratory and female genital tracts, with a prevalence of 12% in community-acquired intra-abdominal infections, as shown in Table 8 of the study by 1.
Importance of Prevotella as a Pathogen
The pathogenicity of Prevotella stems from its production of virulence factors including capsular polysaccharides, adhesins, and various enzymes that facilitate tissue invasion and destruction.
- Prevotella species are a significant component of the normal microbiota in the oral cavity, gastrointestinal tract, and female genital tract, but can become pathogenic under certain conditions.
- The emergence of resistance in B. fragilis group isolates, especially against metronidazole, has important implications in the treatment of surgical infections, as noted in the study by 1.
- Proper specimen collection with anaerobic transport media is essential for accurate diagnosis, as these organisms require special growth conditions in the laboratory.
Treatment of Prevotella Infections
When treating Prevotella infections, clinicians typically use antibiotics such as:
- Metronidazole (500mg orally three times daily for 7-14 days)
- Amoxicillin-clavulanate (875/125mg twice daily for 7-14 days)
- Clindamycin (300-450mg orally four times daily for 7-14 days) The choice of antibiotic should be guided by susceptibility testing and local resistance patterns, as recommended by 1.
- Additionally, many Prevotella strains have developed resistance to beta-lactam antibiotics through beta-lactamase production, making them more challenging to treat.
- The study by 1 highlights the importance of considering the predominant organisms isolated from cultures, including Prevotella, when selecting empiric antimicrobial therapy.
From the Research
Importance of Prevotella as a Pathogen
- Prevotella species are commonly associated with human infections such as dental caries and periodontitis, as well as other conditions like chronic osteomyelitis, bite-related infections, rheumatoid arthritis, and intestinal diseases like ulcerative colitis 2.
- These bacteria possess virulence factors such as adhesins, hemolysins, secretion systems, exopolysaccharide, LPS, proteases, quorum sensing molecules, and antibiotic resistance, which enable them to evolve into well-adapted pathogens capable of causing successful infection and proliferation in host tissue 2.
Antimicrobial Susceptibility of Prevotella
- Studies have shown that Prevotella species exhibit varying levels of susceptibility to different antimicrobial agents, with some species showing high resistance to certain antibiotics 3, 4, 5, 6.
- Amoxicillin-clavulanate, metronidazole, and clindamycin have been found to be effective against Prevotella species, although resistance to these agents has been reported in some cases 3, 4, 5, 6.
- The susceptibility of Prevotella species to antimicrobial agents can vary depending on the species, geographic location, and other factors, highlighting the need for periodic monitoring of antimicrobial resistance patterns 5, 6.
Virulence Factors and Disease Association
- Prevotella species have been found to produce various virulence factors, including adhesins, hemolysins, and proteases, which contribute to their ability to cause disease 2.
- These bacteria have been associated with a range of diseases, including periodontitis, dental caries, and intestinal diseases like ulcerative colitis, highlighting their importance as pathogens 2.
- Further research is needed to understand the role of Prevotella species in disease and to develop effective strategies for prevention and treatment 2.