Which genus is composed of anaerobic Gram-positive cocci commonly isolated in polymicrobial brain abscess?

Which genus is composed of anaerobic Gram-positive cocci commonly isolated in polymicrobial brain abscess?

• A. Veillonella
• B. Peptostreptococcus
• C. Bacteroides
• D. Fusobacterium

Answer: (B)

Anaerobic Gram-positive cocci that are common inhabitants of the oral cavity are a classic contributor to polymicrobial brain abscesses, especially when dental or sinus infections are involved. Peptostreptococcus fits this scenario perfectly: it is an anaerobic Gram-positive coccus that is frequently isolated from such mixed infections and from oral/oral-GI flora. The other options are not Gram-positive cocci, and thus do not match the described genus: Veillonella are Gram-negative cocci, Bacteroides are Gram-negative rods, and Fusobacterium are Gram-negative fusiform rods.

Anaerobic Gram-positive cocci that are common inhabitants of the oral cavity are a classic contributor to polymicrobial brain abscesses, especially when dental or sinus infections are involved. Peptostreptococcus fits this scenario perfectly: it is an anaerobic Gram-positive coccus that is frequently isolated from such mixed infections and from oral/oral-GI flora. The other options are not Gram-positive cocci, and thus do not match the described genus: Veillonella are Gram-negative cocci, Bacteroides are Gram-negative rods, and Fusobacterium are Gram-negative fusiform rods.