After one postoperative day, a patient presents with a fever of 104°F and grey wound drainage. What organism is most likely responsible?

The presentation of a fever of 104°F and gray wound drainage after one day postoperatively raises concern for a specific type of infection. The organism most likely responsible for these findings is Clostridium perfringens. This bacterium is a well-known cause of gas gangrene or clostridial myonecrosis, which can occur in the context of substantial tissue injury or contamination.

Clostridium perfringens can produce a variety of toxins that lead to rapid tissue necrosis and the characteristic gray or brownish drainage often associated with anaerobic infections. The high fever indicates a vigorous systemic inflammatory response, which can occur in cases of significant gas-producing infections. After surgery, particularly in cases with devitalized tissue or hematoma, the risk of Clostridial infection is heightened.

In contrast, Staphylococcus aureus is more commonly associated with purulent infections that typically have more classic pus drainage rather than the specific gray appearance, while also taking a longer period before substantial fever presents. Escherichia coli is more associated with intra-abdominal infections or urinary tract infections but does not typically manifest with the gray drainage seen in this case. Pseudomonas aeruginosa is often implicated in infections involving burn wounds