A 72-year-old man presents to the emergency department with severe right ear pain for the past 2 weeks. He describes the pain as deep, constant, and worse at night. He reports purulent ear drainage and decreased hearing on the right. His medical history is significant for poorly controlled type 2 diabetes mellitus. Vital signs are within normal limits. Physical examination reveals granulation tissue at the floor of the external auditory canal and marked tenderness with manipulation of the auricle. Cranial nerve examination shows mild right-sided facial weakness.
Which of the following is the most appropriate next step in management?
The correct answer is:
A) High-dose intravenous cefepime
This patient’s presentation is classic for malignant (necrotizing) otitis externa, a life-threatening infection of the external auditory canal that can spread to the skull base. It occurs most commonly in elderly patients with diabetes or in immunocompromised individuals. Severe otalgia out of proportion to exam, granulation tissue in the external auditory canal, cranial nerve involvement (especially facial nerve palsy), and purulent otorrhea are key features.
The most common causative organism is Pseudomonas aeruginosa. Management requires prolonged high-dose intravenous antipseudomonal antibiotics (e.g., ciprofloxacin, cefepime, or piperacillin-tazobactam), often guided by cultures and imaging.
Answer choice B: Oral amoxicillin-clavulanate therapy, is incorrect. This regimen is appropriate for uncomplicated otitis media but does not adequately cover Pseudomonas and is insufficient for invasive disease.
Answer choice C: Placement of a tympanostomy tube, is incorrect. Tympanostomy tubes are used for recurrent or chronic otitis media, not infections of the external auditory canal.
Answer choice D: Topical acetic acid ear drops, is incorrect. Topical therapy alone is appropriate for uncomplicated otitis externa but is inadequate for malignant otitis externa with skull base involvement.
Answer choice E: Urgent mastoidectomy, is incorrect. Surgical intervention is rarely first-line and is reserved for cases refractory to medical therapy or with abscess formation.
Key Learning Point
Malignant otitis externa presents in elderly or diabetic patients with severe ear pain, granulation tissue, and possible cranial nerve deficits. It requires prolonged intravenous antipseudomonal antibiotics.
