Snapshot A 12-year-old boy presents to his pediatrician for ear pain. His ear pain began approximately 5 days ago and is associated with ear itching and mild hearing difficulty. His past medical history is unremarkable. He recently joined the swimming team of his school. Physical examination is notable for otalgia with palpation of the tragus and traction of the pinna. There is mild edema and swelling of the external auditory canal with poor visualization of the tympanic membrane. His ear is cleaned and is started on topical hydrocortisone and ciprofloxacin. Introduction Definition inflammation of the external ear canal Epidemiology Incidence acute uncomplicated otitis externa is most common in children malignant otitis externa is more common in immunocompromised patients (e.g., elderly, diabetes, HIV, and on immunosuppresants) Risk factors prolonged swimming Etiology Pseudomonas aeruginosa (most common) Staphylococcus aureus Pathogenesis disruption of protective barriers (e.g., skin or cerumen) within the external ear canal leads to cellulitis cerumen creates an acidic environment that impairs bacterial and fungal growth inflammation and edema in the external ear creates a favorable for bacterial growth this is because impaired cerumen and epithelial migration makes the pH of the external ear more alkalotic Presentation Symptoms pruritus otalgia hearing loss Physical exam pain with manipulation/pulling of the ear Studies Making the diagnosis this is a clinical diagnosis Differential Otomycosis differentiating factors fungal filaments and spores that appear like mold growing under magnified vision Contact dermatitis differentiating factors lack of response to appropriate treatment to otitis externa Perichondritis infection of connective issute of the ear that involves the cartilage management anti-pseudomonal antibiotics +/- incision and drainage Treatment Conservative cleaning the external ear indication first step in management comments involves removing cerumn, desquamated skin, and purulent material from the ear canal facilitates penetration of ear drops and healing Medical topical medications indication mild disease acetic acid and hydrocortisone moderate disease hydrocortisone and ciprofloxacin hydrocrotisone and neomycin and polyxin severe disease same as moderate disease but with also a wick placed systemic antibiotics indication in infection that extends beyond the external auditory canal in immunocompromised patients comments topical antibiotics are also given medications quinolones Complications Malignant otitis externa most commonly seen in immunocompromised patient caused by spread of the infection to the bone and marrow from the skin the diagnosis is supported by CT and MRI findings of bone involvement Language development delays children with a history of recurrent ear infections presenting with signs of social or language development delays should be evaluated for hearing impairment with an audiometry test.