Abstract & Commentary

Otoscopic Signs of Otitis Media

By Hal B. Jenson, MD, FAAP, Dean, Western Michigan University School of Medicine, Kalamazoo, MI, is Associate Editor for Infectious Disease Alert.

Dr. Jenson reports no financial relationship to this field of study.

Synopsis: In children, a bulging tympanic membrane is invariably associated with acute otitis media. Antimicrobial treatment of childhood acute otitis media should be reserved for children with this finding. Tympanic membrane abnormalities in the absence of bulging indicate otitis media with effusion.

Source: Shaikh N, et al. Otoscopic signs of otitis media. Pediatr Infect Dis J 2011;30:822-826.

A total of 783 children 6-24 months of age were followed for an entire respiratory season by four experienced otoscopists using pneumatic otoscopy of one ear, randomly selected for each child. At each visit, the tympanic membranes were examined for color (amber, blue, gray, pink, red, white, yellow), translucency (translucent, semi-opaque, opaque), position (neutral, retracted, bulging), mobility (decreased, not decreased), and areas of marked redness as distinct from mild or moderate redness (present, absent).

In ears diagnosed with acute otitis media (AOM), the most common findings were bulging (96%), opacification (100%), white or yellow discoloration (90%), marked redness (20%), and decreased mobility (99%). Retraction was not found in ears with AOM. In ears with otitis media with effusion, the most common findings were opacification (98%), white or yellow discoloration (79%), decreased mobility (69%), and retraction (37%). In ears with no effusion the rates were, respectively, 0.5%, 0%, 0.2%, and 2%. Neither bulging nor marked redness were found in any ears diagnosed with otitis media with effusion, or in any ears with no effusion.

In a substudy, 135 randomly selected endoscopic tympanic membrane images from these children were evaluated by two otolaryngologists and five pediatricians from throughout the United States. These physicians had been in practice a mean of 32 years. In 51 (38%) of these 135 images, hair and/or cerumen obscured a small portion of the tympanic membrane. Colors were calibrated using an external colorimeter to ensure uniformity of color rendition on a computer monitor for each physician.

In 120 of the 135 images (90%), the diagnosis made by the majority of these physicians agreed with the diagnosis by the examining otoscopists — despite the absence of any information about the patient's symptoms, the ability to assess mobility of the tympanic membrane, and partially obscured parts in 38% of images.

Commentary

The distinction between AOM, and otitis media with effusion is a very common and important pediatric clinical issue. One of the greatest pressures on development of community antimicrobial resistance has been the high rate of antibiotic use (or overuse) for ear infections, including for otitis media with effusion where antimicrobial therapy has limited benefit.

Historically, there has been variability in the criteria used to diagnose AOM, even in clinical trials. This study shows that highly experienced clinicians rely on the presence of a bulging tympanic membrane as being pathognomonic for acute otitis media, and rarely make this diagnosis in its absence, even in the presence of other findings. In the absence of a bulging tympanic membrane, other abnormalities such as discoloration, opacification, and impaired mobility are assessed to be indicative of otitis media with effusion.

A bulging tympanic membrane is invariably the most useful physical finding for the diagnosis of childhood AOM, and antimicrobial therapy should be limited, reserved for those children with this finding.