Most likely pathogen
D) Clostridium perfringens. Autoclaving at only 100°C fails to achieve sterilization (required 121–132°C), allowing heat-resistant spores—especially from clostridial species—to survive and cause early, severe postoperative infections 1. Clostridial myonecrosis is a classic early postoperative complication and C. perfringens is the most frequent cause in trauma/surgical settings, aligning with the clinical scenario of a sterilization failure that did not inactivate spores 2, 3.
- Autoclave requirement: Steam sterilization must reach 121–132°C; 100°C is inadequate and permits survival of spore-forming organisms 1.
- Early SSI pattern: Within 48 hours, SSIs are “almost always” due to streptococci or clostridia; spore survival points toward clostridia when sterilization fails 2.
- Clostridial etiology: C. perfringens is the most common cause of clostridial myonecrosis in postoperative/trauma contexts, driving morbidity, mortality, and QOL loss if instruments are contaminated by spores 3.
Pitfalls/Caveats:
- Do not attribute this to typical non-spore-forming flora (E. coli, Listeria, S. pyogenes, Pseudomonas) when sterilization failed at 100°C; spores are the key survival advantage here 1.
- Rapid recognition and management of suspected clostridial SSI are critical to reduce mortality (urgent wound exploration/debridement plus appropriate antibiotics) 2, 3.