From the Guidelines
Peptostreptococcus species is an anaerobic gram-positive cocci that appears in pairs and clusters under microscopic examination. This bacterium is a common part of the normal human microbiota, particularly found in the oral cavity, gastrointestinal tract, and genitourinary tract. According to the study by 1, Peptostreptococcus species is one of the anaerobic bacteria that can be isolated from intra-abdominal infections, with a frequency of 17% in patients with community-acquired complicated intra-abdominal infection. The study also notes that anaerobes, such as Bacteroides fragilis and Peptostreptococcus species, are commonly present in infections derived from the distal small bowel and colon.
Some key characteristics of Peptostreptococcus species include:
- Anaerobic growth
- Gram-positive cocci appearance
- Presence in pairs and clusters
- Commonly found in oral, gastrointestinal, and genitourinary tracts
- Can cause infections, particularly in cases of intra-abdominal infection
It's worth noting that while Staphylococcus aureus is also a gram-positive cocci, it is not typically anaerobic, but rather facultatively anaerobic, meaning it can grow with or without oxygen 1. In contrast, Peptostreptococcus species is obligately anaerobic, meaning it requires an oxygen-free environment to grow.
The study by 1 also supports the idea that anaerobic gram-positive cocci, such as Peptostreptococcus species, are important pathogens in intra-abdominal infections, and that coverage against these organisms should be provided in empirical antibiotic regimens. However, the most recent and highest quality study 1 provides more specific information on the frequency and characteristics of Peptostreptococcus species in intra-abdominal infections.
From the Research
Bacteria Identification
- The bacteria that is an anaerobe, gram-positive cocci in pairs and clusters is Peptostreptococcus anaerobius 2, 3, 4.
Characteristics
- Peptostreptococcus anaerobius is a gram-positive anaerobic coccus (GPAC) found in the gastrointestinal and vaginal microbiota 3.
- GPAC are part of the normal flora of all mucocutaneous surfaces and are often isolated from infections such as deep organ abscesses, obstetric and gynecological sepsis, and intraoral infections 4.
Antimicrobial Susceptibility
- Peptostreptococcus anaerobius has shown to be more resistant to antimicrobials than other GPAC 2, 5.
- P. anaerobius is resistant to penicillin, ampicillin, ciprofloxacin, and levofloxacin, and displays intermediate susceptibility to ampicillin-sulbactam and amoxicillin-clavulanic acid 3.
- Antimicrobial susceptibility testing (AST) should be performed on P. anaerobius isolates due to their unpredictable AST patterns 3.