Treatment of otitis externa in children.

Inflammation of the external auditory canal can be localised or diffuse, and acute or chronic. Predisposing conditions include external trauma, loss of the canal's protective coating, maceration of the skin from water or humidity, and glandular obstruction. Acute otitis externa is generally caused by Pseudomonas aeruginosa or Staphylococcus aureus. Management of patients with otitis externa includes debridement, topical therapy with acidifying and antimicrobial agents, and systemic antimicrobial therapy when indicated. The management of patients with chronic otitis externa includes cleansing and debridement accompanied by topical acidifying and drying agents. This is followed by topical antibiotics and corticosteroid preparations. Surgery is mainly used to allow cleansing and aeration and/or removal of the scarred tissue. Patients with acute localised otitis externa (furunculosis) are treated with local heat and systemic antibiotics in the inflammatory stage, and drainage in the abscess state. Mycotic external otitis is managed with topical acidifying and antifungal agents, while viral (herpes) infection is treated with topical and systemic aciclovir (acyclovir). Patients with necrotising (malignant) external otitis, which is mainly caused by P. aeruginosa and S. aureus, are treated with systemic antibiotics and, rarely, by surgical debridement. Therapy for eczematous otitis externa is first directed at the secondary infection, and thereafter at the primary dermatological condition. Prevention of recurrent external otitis is aimed at minimising ear canal trauma and the avoidance of exposure to water. Preventative use of topical acidifying agents or 70% alcohol is also advocated.