I have been diagnosed with acute otitis media. I surfed the Net and found out that normally children are the ones affected with this, but I'm 31 years old. My doctor prescribed some antibiotics and an eardrop. I'm feeling better now (after 10 days of medication), but I can still feel the fluid inside my ear. Will the fluid just disappear? How long will it take? I work as a DJ, and I'm worried I might lose my hearing.

Wilson

Acute otitis media is a short-term (acute) middle-ear inflammation (otitis media). It is almost always due to a bacterial infection. You are correct that this sort of infection is much more common in children than in adults, but adults do, occasionally, get acute otitis media.

The middle ear (the area behind the eardrum) is normally an air-filled space. In the early days of an infection, this space is filled with dead white blood cells and bacteria -- pus, in other words. Gradually, the pus is replaced by a clear, yellow fluid. Days to weeks later, the yellow fluid (the medical term is serous effusion) is replaced by air.

You probably have a serous effusion at present. This may take one to four weeks to resolve. Occasionally, the fluid does not go away, even after several weeks. If that happens, an ear, nose and throat specialist could treat this problem by making a very small cut in your ear drum, suctioning out the fluid, and placing a tiny plastic tube into the hole to help ventilate the middle-ear space. The tube could be removed at a later date, or you could wait for it to fall out by itself, 6-18 months after it is inserted.

The underlying cause of most middle-ear infections is eustachian tube dysfunction. The eustachian tubes are tubes of muscle and cartilage that extend from each middle-ear space to the top of the throat (nasopharynx). The tubes are normally closed, but they can "pop" open as needed to ventilate your middle-ear spaces. That's what the tubes are for -- to allow air up into the middle-ear spaces. Children are more prone to middle-ear infection than adults simply because the eustachian tube in children does not function as effectively as it does in adults.

If you had a very long, skinny finger, you could pass it through one nostril and down to tickle the opening of one of your eustachian tubes in the throat. Anything that drains from your nose goes down the back of your throat, right past these openings. This explains why acute otitis media is often preceded by a cold, flu or sinus infection. In each case, a nasty mix of mucus and pus drains past the eustachian-tube openings, inflaming them and thereby making it difficult for the tubes to do their job. That may eventually lead to a situation in which the air pressure in the middle ear is lower than the air pressure in the throat. If this pressure difference is great enough, there is a tendency for bacteria-laden saliva and nasal mucus to get sucked up from the nasopharynx into the middle-ear space. The result is an infected middle ear.

Rarely, eustachian-tube problems are due not to inflammation (from sinusitis, allergy, cold or flu) but to obstruction from a tumor. A tumor should be suspected in adults when middle-ear infections are recurrent, when a serous effusion fails to resolve after several weeks, or when there are large lymph nodes in the patient's neck. Since the eustachian-tube openings are difficult to examine by standard methods, an ear, nose and throat specialist will need to examine you by passing a flexible fiber-optic scope down a nostril to view the nasopharynx. Occasionally, further studies (such as a CT scan) may be necessary.