Diagnosing ear infections

Q: We’re mystified by ear infections: When we take our 2-year-old to multiple doctors, the diagnoses aren’t consistent. One will say she has no ear infection at all. Another will say she has a severe ear infection!

A: To better understand variation on diagnoses of ear infections, we may need to take a step back and more clearly define what’s infected. Typically, when a child is diagnosed with an ear infection, what the pediatrician is diagnosing is a bacterial infection of fluid in the middle-ear space. The middle-ear space is divided from the outer-ear space by a thin membrane called the tympanic membrane. 

A healthy, non-infected middle-ear space has air in it. Because of the membrane barrier, sometimes there can be built-up fluid in that space. Just the presence of fluid doesn’t mean there’s an infection, however. 

Remember that an ear infection can continue to change from hour to hour and day to day.

For a true diagnosis of ear infection, there needs to be the presence of fluid as well as other signs of infection. Other signs — such as redness of the tympanic membrane or the outer-ear canal — also can be caused by crying, fevers, upper respiratory infections (colds), ear trauma or recent manipulation of the outer ear space from removing earwax. 

To accurately diagnose a true ear infection, your pediatrician needs to be able to clearly see the tympanic membrane and middle-ear space. The outer ear canal is sometimes quite full of extra earwax, which can block the view and make it more difficult to diagnose.

Think back to your most recent visit to the pediatrician and how cooperative your child was with any of the exam, and then especially with the part where the pediatrician was trying to get a good look inside the ear. (If your child is anything like my toddler son, she’s realized that going to the pediatrician’s office can mean shots!)

Also remember that an ear infection can continue to change from hour to hour and day to day. Unless you’re seeing all the different doctors at the same time on the same day, there’s a chance that they’re all correctly diagnosing what they see at the time of each exam. 

Some may see fluid, some may see fluid with other signs of infection and some may see a normal middle-ear space in a child who has other sick symptoms, such as fever.