Definition of Acute Otitis Media (AOM)

A diagnosis of AOM requires:

1. a history of acute onset of signs and symptoms,
2. the presence of middle-ear effusion (MEE), and
3. signs and symptoms of middle-ear inflammation.

Elements of the definition of AOM are all of the following:

1. Recent, usually abrupt, onset of signs and symptoms of middle-ear inflammation and MEE

2. The presence of MEE that is indicated by any of the following:

1. 1. Bulging of the tympanic membrane
   2. Limited or absent mobility of the tympanic membrane
   3. Air-fluid level behind the tympanic membrane
   4. Otorrhea

3. Signs or symptoms of middle-ear inflammation as indicated by either

1. 1. Distinct erythema of the tympanic membrane or
   2. Distinct otalgia (discomfort clearly referable to the ear[s] that results in interference with or precludes normal activity or sleep)