Symptoms and otoscopic signs in bilateral and unilateral acute otitis media

Bilateral acute otitis media (AOM) is considered more severe than unilateral AOM, and several guidelines recommend more active treatment and/or follow-up of bilateral AOM. We studied whether bilateral AOM is a clinically more severe illness than unilateral AOM by comparing symptoms and otoscopic signs between bilateral and unilateral AOM.

Two hundred thirty-two children aged 6 to 35 months diagnosed with AOM were eligible. We surveyed the symptoms with a structured questionnaire and recorded the otoscopic signs systematically.

Ninety-eight children had bilateral and 134 children unilateral AOM. Children with bilateral AOM were more often <24 months than children with unilateral AOM (87% vs 75%; P = .032). Fever (≥38°C) occurred in 54% and 36% (P = .006) and severe conjunctivitis in 16% and 44% (P = .047) of children with bilateral and unilateral AOM, respectively. In 15 other symptoms, we found no overall differences even when adjusted with age. We observed the following severe otoscopic signs in the bilateral and unilateral AOM group, respectively: moderate/marked bulging of tympanic membrane (63% and 40%; P = .001), purulent effusion (89% and 71%; P = .001), bulla formation (11% and 10%; P = .707), and hemorrhagic redness of tympanic membrane (7% and 10%; P = .386).

Bilateral AOM seems to be a clinically only slightly more severe illness than unilateral AOM. Therefore, when assessing AOM severity, bilaterality should not be used as a determining criterion; instead, the child's symptomatic condition together with otoscopic signs should also be taken into consideration.