Infectious Disease· Topic 7.3 Upper respiratory tract infections· 7.3.4

Acute otitis media

Acute otitis media is a suppurative middle ear infection, mostly in young children, diagnosed by otoscopy showing a bulging, erythematous tympanic membrane with an effusion, and it is treated with observation or amoxicillin depending on age and severity.

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What this article covers

  • Overview

    Suppurative middle ear infection: acute otitis media (AOM) is a suppurative infection of the middle ear cavity, most often following an upper respiratory infection that produces eustachian tube…

  • Epidemiology

    Peak incidence in infancy and toddlerhood: rate peaks between 6 and 12 months of age, with most children affected before age 2; about 60% of children develop one or more episodes before 4 years of age.

  • Risk factors

    Recent or concurrent upper respiratory infection: nasopharyngeal inflammation obstructs the eustachian tube isthmus and is the usual antecedent event.

  • Pathophysiology

    Eustachian tube obstruction is the initiating event: viral upper respiratory infection causes mucosal edema that narrows the eustachian tube isthmus, its narrowest portion.

  • Clinical features

    Diagnosis requires both an inflamed and a bulging tympanic membrane plus an effusion: the defining triad is (1) middle ear effusion, (2) signs of acute inflammation of the tympanic membrane (bulging…

  • Differential diagnosis

    Otitis media with effusion: fluid in the middle ear without bulging, erythema, or other acute inflammatory signs; the membrane is dull and retracted, not bulging; see otitis media with effusion.

  • Diagnosis

    AOM is a clinical diagnosis; no confirmatory laboratory test exists: the diagnosis rests on otoscopic examination and history alone, using the triad above (acute onset, middle ear effusion, and…

  • Management

    First decide observation versus antibiotics, based on age, laterality, and severity: for a child older than 6 months with mild, unilateral AOM and reliable follow-up, either observation with close…

  • Complications

    Tympanic membrane perforation: the most common complication; usually heals spontaneously but can lead to recurrent otorrhea; see tympanic membrane perforation.

  • Prognosis

    Excellent overall outcome: most episodes resolve without sequelae, whether observed or treated with antibiotics.

  • Prevention

    Breastfeeding: exclusive breastfeeding is protective and should be encouraged.

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