Professional and Linguistic Assessments Board (PLAB) Practice Exam

What is the first-line treatment for otitis externa?

1. Topical lidocaine

2. Topical ciprofloxacin

3. Topical gentamicin

4. Oral amoxicillin

The correct answer is: Topical gentamicin

In the context of treating otitis externa, the first-line treatment typically involves the use of topical antibiotic agents. Topical ciprofloxacin and topical gentamicin are both effective in addressing the infection; however, topical ciprofloxacin is preferred in many guidelines due to its broader coverage, particularly for Pseudomonas aeruginosa, which is a common pathogen in external ear infections. Topical lidocaine may provide symptomatic relief due to its analgesic properties, but it does not address the underlying infection and therefore is not considered a first-line treatment. Oral amoxicillin is generally ineffective for otitis externa, particularly due to its limited efficacy against the usual pathogens involved, including Pseudomonas. When selecting the appropriate treatment, it's essential to consider the local resistance patterns and the specific characteristics of the infection. Topical ciprofloxacin’s broad-spectrum activity and effectiveness against common pathogens makes it a preferred choice in the initial management of otitis externa, while topical gentamicin, although effective, may have limitations based on resistance and is not universally recommended as first-line therapy.