10/7/03 Otitis media - Clinical aspects (Part II)SummaryIn this Current Literature section of the AADMC I have previously reviewed in 9/03 a part of an excellent review of clinical aspects of otitis media (OM) focused on the general principles and unreliability/insensitivity of some components in the history (ear tugging without otalgia, fever). Therefore the patient history is often unreliable in diagnosing OM. What about physical findings in diagnosing OM? A high quality physical exam is dependent on an adequate light source and sufficient energy supply, and an airtight seal. The latter is usually better obtained with a permanent (reusable) specula of the size appropriate for the varying size of the ear canal (2,3,4,5 mm diameter option) rather than disposable specula. If the tympanic membrane is obscured by cerumen, the latter must be removed, either manually (curetting under direct visualization) or by irrigation with sterile saline at body temperature (if TM perforation is not suspected). If the cerumen is voluminous/hard instillation of a cerumen-lysing agent 30 minutes in advance (Ceruminex or 1% docusate sodium solution) may be needed.) Four qualities of the TM should be considered: 1) Color (erythema suggests acute OM but can also be due to crying or irritation secondary to the irrigation procedure); 2) thickness (can you see the middle ear structures?); 3) position (retracted vs normal vs bulging) and 4) mobility (most important in suspecting middle ear infusions). However, evaluation of TM mobility requires pneumatic otoscopy, a technique that requires considerable practice. When TM mobility findings in pneumatic otoscopy are equivocal, tympanometry, requiring specialized equipment, may be helpful in determining whether OM with effusion is present. A newer approach is special gradient acoustic reflectometry, also requiring specialized equipment. The latter approach has the same sensitivity as tympanometry but has the advantage of not requiring a tight seal (often requiring patient cooperation). Tympanocentesis is the gold standard for determining (and characterizing) middle ear effusions. It is a technically more difficult procedure. However, with adequate training, a large majority of pediatricians can correctly perform this procedure. Reference Current Allergy and Asthma Rep 2003; 3:313-20 Editor's Comments I found this a very instructive review which should be of considerable help, particularly to physicians seeing young children in their practice. Since chronic allergic rhinitis is a major risk factor for recurrent OM, this discussion is relevant to the field of Allergy and Immunology.
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