Otitis Media Diagnosis

When patients present with symptoms of otitis media such as pain in the ear, it is important to make an accurate diagnosis using appropriate techniques, as the pain may be indicative of another condition.

Clinical Examination

Merely the clinical history not enough to determine the involvement of otitis media and visualization is the tympanic membrane is needed to make a diagnosis. This is usually conducted with a pneumatic otoscope attached to a rubber bulb, which helps to view the tympanic membrane and assess its mobility.

The signs that indicative or otitis media upon visual inspection of the membrane include:

• Bulging and fullness
• Cloudiness
• Redness (erythema)

Occasionally it can be difficult to confirm diagnosis with visual examination of the eardrum. This may happen because the ear canal is very small, making it difficult to get a clear view. Earwax can also obstruct the view through the ear canal and, if this is the case, it may be removed with a blunt cerumen curette or wire loop.

It is also possible to make a false diagnosis based on the circumstances when the diagnosis was made. For example, if a young child is upset and crying, the eardrum may look red and inflamed similar to otitis media, as a result of the distension of small blood vessels on it.

Differential Diagnosis

The two most common types are acute otitis media (AOM) and otitis media with effusion (OME). It is important to differentiate between these during diagnosis, as the treatment differs significantly, particularly in regards to the use of antibiotics. It has been suggested by some practitioners that the best way to determine the type of otitis media is by observing the bulging of the tympanic membrane.

Acute Otitis Media (AOM)

For children that exhibit moderate to severe inflammation of the tympanic membrane or have recently noticed drainage from the ear, also known as otorrhea, the symptoms are not likely to be due to external otitis. In addition, mild bulging of the eardrum with pain onset within 48 hours and intense redness is also diagnostically indicative of acute otitis media.

Otitis Media with Effusion (OME)

Otitis media with effusion is also sometimes referred to as serous otitis media or secretory otitis media.

It is a build up of fluid or effusion that occurs with the middle ear, as a consequence of Eustachian tube dysfunction and the resulting negative pressure in the middle-ear space.

There may not be any pain or bacteria infection associated with OME, although the fluid often inhibit hearing ability when it interferes with the normal sound wave vibration of the eardrum.

Over the timespan of several weeks, the fluid in the middle ear can become very thick and resemble the consistency of glue, which has led to the condition being referred to as glue ear occasionally. This also increases the likelihood of associated conductive hearing impairment.

Some risk factors for OME within the first two years of life are:

• Feeding infants whilst lying down
• Child care from an early age
• Smoking by parents
• Minimal or lack of breastfeeding
• Large amount of time in childcare

Other Types

Chronis suppurative otitis media involves a bacterial infection of the middle-ear that persists for several weeks or longer and hole in the tympanic membrane. The pus may accumulate and drain outside the ear, although it may also only be visible on inspection with an otoscope or binocular microscope. This is more common in individuals with poor Eustachian tube function and offer precipitates hearing impairment.

Viral otitis may present with blisters on the outside of the tympanic membrane, also known as bullous myringitis.

Adhesive otitis media involves a thin retracted eardrum that is vacuumed into the middle-ear space and sticks to the ossicles and bones in the middle ear.

References

• http://www.nidcd.nih.gov/health/hearing/pages/earinfections.aspx
• http://www.nlm.nih.gov/medlineplus/ency/article/007010.htm
• http://www.healthline.com/health/ear-infection-acute#Overview1
• http://emedicine.medscape.com/article/859316-overview
• http://www.cdc.gov/getsmart/antibiotic-use/URI/ear-infection.html