What is the chief pathogen associated with acute external otitis?

The chief pathogen associated with acute external otitis, commonly known as swimmer's ear, is Pseudomonas aeruginosa. This organism is a Gram-negative bacterium that thrives in moist environments, making it particularly adept at infecting the external ear canal, especially after water exposure.

Pseudomonas aeruginosa is known for its ability to cause a variety of infections and is often implicated in individuals with water exposure, such as swimmers. Its virulence factors, including biofilm formation and resistance to many antibiotics, contribute to its prevalence as a causative agent in acute external otitis.

Other pathogens like Staphylococcus aureus may also be found in external ear infections, but Pseudomonas aeruginosa is recognized as the most common offender in cases of acute external otitis. The risk factors and presentation of the infection further support this association, highlighting the need for targeted treatment options specifically effective against Pseudomonas.