Which organism is classically associated with otitis externa?

Which organism is classically associated with otitis externa?

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

Answer: (C)

Otitis externa is an infection of the external auditory canal, and the organism most characteristically linked to it is Pseudomonas aeruginosa. This Gram-negative rod thrives in moist environments, like the ear canal after swimming, and it’s a common cause of the classic, foul-smelling discharge and canal swelling seen with this condition. While Staphylococcus aureus and Streptococcus pyogenes can cause ear infections in some cases, they are not the archetypal pathogens for otitis externa. Escherichia coli is not typically associated with this condition.

Otitis externa is an infection of the external auditory canal, and the organism most characteristically linked to it is Pseudomonas aeruginosa. This Gram-negative rod thrives in moist environments, like the ear canal after swimming, and it’s a common cause of the classic, foul-smelling discharge and canal swelling seen with this condition. While Staphylococcus aureus and Streptococcus pyogenes can cause ear infections in some cases, they are not the archetypal pathogens for otitis externa. Escherichia coli is not typically associated with this condition.