Version August 2025
| Infection adjacent to surfaces that normally harbor anaerobes as normal flora |
| Abscess formation or tissue necrosis |
| Putrid odor |
| Gas formation |
| Gram stain of exudate showing polymicrobial flora or organisms with morphologic features of anaerobes |
| Classic features of clostridial syndromes: tetanus, botulism, Clostridium perfringens food poisoning, gas gangrene, Clostridioides difficile-induced diarrhea or colitis, enteritis necroticans |
| Infections that, by prior experience, usually involve anaerobic bacteria (eg, bite wounds) |
