Which organism is most likely to be implicated in an outbreak associated with outpatient whirlpool wound therapy?

• A. Pseudomonas aeruginosa
• B. Staphylococcus aureus
• C. Escherichia coli
• D. Streptococcus pyogenes

Answer: (A)

Outpatient whirlpool wound therapy outbreaks are classically caused by organisms that thrive in moist environments and resist routine disinfection. Pseudomonas aeruginosa fits this scenario perfectly. It loves warm, damp settings like whirlpool devices and plumbing, and it readily forms biofilms on surfaces, which protect it from sanitizers and allow ongoing contamination of the water used on wounds. When contaminated water comes into contact with open or healing wounds, this organism can invade and establish infection, leading to outbreaks that are difficult to treat because Pseudomonas is often naturally resistant to multiple antibiotics.

While Staphylococcus aureus is a common skin inhabitant and can cause wound infections, it is not as characteristically linked to water-logged medical equipment as Pseudomonas. Escherichia coli and Streptococcus pyogenes are typically associated with other routes of transmission, such as fecal contamination or non-waterborne wound infections, and are less likely to be the primary culprits in whirlpool-related outbreaks.