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Otitis externa, or “swimmer's ear,” is characterized by pruritus, pain, and tenderness of the external ear. Erythema and edema of the external auditory canal, otorrhea, crusting, and hearing impairment may also be present. Pain is elicited with movement of the pinna or tragus. Risk factors for development of otitis externa include swimming, trauma of the external canal, and any process that elevates the pH of the canal.
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The most common organisms implicated in otitis externa are Pseudomonas aeruginosa, Enterobacteriaceae and Proteus species, and Staphylococcus aureus, with P aeruginosa being the most common organism causing malignant otitis externa. Otomycosis, or fungal otitis externa, is found in tropical climates and in the immunocompromised or subsequent to long-term antibiotic therapy. Aspergillus and Candida are the most common fungal pathogens.
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The treatment of otitis externa includes analgesics, cleaning the external auditory canal, acidifying agents, topical antimicrobials, and occasionally topical steroid preparations. Ofloxacin otic 5 drops 2 times daily, acetic acid/hydrocortisone otic 5 drops 3 times daily (do not use with perforated TM), and ciprofloxacin/hydrocortisone otic 3 drops 2 times daily are commonly used for 7 days to treat otitis externa. If significant swelling of the external canal is present, a wick or piece of gauze may be inserted into the canal to allow passage of topical medications.
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Malignant otitis externa is a potentially life-threatening infection of the external auditory canal with variable extension to the skull base. In greater than 90% of cases, it is caused by Pseudomonas aeruginosa. Elderly, diabetic, and immunocompromised patients are most commonly affected. Diagnosis of malignant otitis externa requires a high index of suspicion. Computed tomography (CT) is necessary to determine the extent and stage of the disease. Emergent otolaryngologic (ENT) consultation, tobramycin 2 milligrams/kilogram IV and piperacillin 3.375 to 4.5 grams IV, or ceftriaxone 1 gram IV, or ciprofloxacin 400 milligrams IV, and admission to the hospital are mandatory.
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The incidence and prevalence of otitis media (OM) peak in the preschool years and decline with advancing age. The most common bacterial pathogens in acute OM are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. The predominant organisms involved in chronic OM are S aureus, P aeruginosa, and anaerobic bacteria.
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Patients with OM present with otalgia, with or without fever; occasionally, hearing loss and otorrhea are present. The tympanic membrane (TM) may be retracted or bulging and will have impaired mobility on pneumatic otoscopy. The TM may appear red as a result of inflammation or may be yellow or white due to middle ear secretions.
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A 10-day course of amoxicillin 250 to 500 milligrams PO 3 times daily for 7 to 10 days is the preferred initial treatment for OM. Alternative agents include azithromycin 500 milligrams PO daily for 1 day then 250 milligrams PO daily for 4 days, or cefuroxime 500 milligrams PO 2 ...