Is it normal for a child's ear to have a greenish discharge all the time, even after ear tubes have been in place for eight months? My doctor says that's okay, but I'm not so sure. Also, what is the main purpose of the tubes? Is it to prevent hearing loss or help with infection?

M.

It is NEVER normal for a child to have green drainage from an ear, regardless of whether the child has tubes or not! What I find most shocking about your doctor's comment is that I have heard this before. I'm not sure if I will ever understand such a statement.

Some children need ventilation tubes (what you call "ear tubes") in order to reduce the number of ear infections they have. Since recurrent ear infections may lead to hearing loss, then it is fair to say that tubes help prevent hearing loss and help with infection. Also, some children have fluid behind the eardrums that persists despite treatment with antibiotics, decongestants and antihistamines. This fluid usually causes a significant hearing loss. Ventilation tubes are very helpful for this condition, too.

Ventilation tubes permit air to pass into the middle ear. The middle ear (the space behind the eardrum) is normally an air-filled space. Air gets into this space via the eustachian tubes, tubes of muscle and cartilage that open in the back of the throat and extend upward to each middle ear space. The eustachian tubes are the structures that pop when we "pop our ears." Many children have difficulty popping their ears. This can lead to underventilated middle-ear spaces, which are more prone to infection and the buildup of fluid. An ear, nose and throat surgeon can solve this problem by placing a tiny plastic tube into the drum of the affected ear. Air passes freely through the tube, so it no longer matters whether the eustachian tubes are doing their job. Since usually both eustachian tubes are affected, a tube is usually placed in each eardrum.

Green discharge from the tube indicates a middle-ear infection. If this is present "all the time," then the infection is clearly chronic. Persistent drainage from a tube is one of the risks of ventilation tube placement. The chance that this will occur is 1 percent to 5 percent. Most children with ventilation tubes do NOT have persistent drainage. Far more typical is for the child to have occasional drainage when he or she has an ear infection.

Both acute and chronic drainage are treatable. Different practitioners approach these problems in different ways, and I can only tell you how I deal with each situation.

For acute drainage, I ask parents whether the child looks sick. Is he or she in pain? Does he or she have a normal appetite? A fever? If so, I treat the child with oral antibiotics and an antibiotic eardrop. If not, I treat the child with only an antibiotic eardrop. Eardrops accomplish two purposes -- they medicate the ear, but perhaps more importantly, they help keep the tube from clogging with pus.

For chronic drainage, I obtain a sample of the pus draining from the ventilation tube and send it to a microbiology lab. There, they culture (grow) the organisms in the pus and test a variety of antibiotics against them. The lab will then tell me what bacteria species are causing the infection and what antibiotics are effective against them. My next step is to find two different antibiotic eardrops that are effective and treat the child with BOTH drops. If the drainage persists despite this approach, I would repeat the procedure, again obtaining a sample of pus for culture and antibiotic-sensitivity testing. I have found this to be an effective technique for dealing with very tough cases, and I have not yet had to repeat the procedure.