Doctors don't always get ear infections right

It's a ritual: A poor kid is up all night crying and tugging at an ear. The parents bring the child to the doctor, who diagnoses an ear infection and gives antibiotics. Though most parents accept this treatment, authorities increasingly wonder if it hurts more than it helps.

First, a recent study suggests that pediatricians probably can't make the diagnosis reliably more than half the time. Second, most of the drugs given for ear infections probably don't help anyway. As a result, hundreds of millions of dollars' worth of antibiotics have been prescribed unnecessarily to children, leading to increasingly resistant microbes. Last month, the American Academy of Pediatrics issued new guidelines for diagnosing ear infections and cutting down on the overuse of antibiotics.

When I worked in a pediatric clinic, I'd see almost 30 children with suspected ear infections on a winter day. Many were like 15-month-old Ernie, who bucked like a bronco when I stuck the otoscope in his ear. As his father held Ernie, I got a better look.

Ernie's case illustrates why ear pain doesn't always mean ear infection. Ernie's ear canal was clogged with thick earwax, which is common in many healthy children. With a swab, I scooped the peanut-buttery material out, and barely saw Ernie's eardrum beyond it. Eardrums are normally as clear as plastic wrap, and stretch taut to cover the inner ear like a porthole. This inner chamber -- behind the eardrum -- is where most ear infections occur.

Infections get there through a back entry. At the back of the throat, there's a tiny tunnel called the Eustacian tube that connects up to the inner ear. In an airplane, one realizes how critical this tube is. When air pressure drops outside, the eardrum stretches out like a bubble being

blown. It hurts. When you swallow, the Eustacian tube opens to depressurize the inner ear, and the pain is gone. Since Ernie had mucus in his throat from a cold, his Eustacian tube was gummed up. As the inner ear loses air slowly -- like a tire left alone for a long time -- Ernie's eardrum slowly got sucked back. Since the ear couldn't depressurize, it hurt, though there was no infection inside. Here it's worth mentioning a fascinating study. In 2001, two doctors showed videotapes of ear exams to more than 500 pediatricians. There were no squirming children or earwax to remove -- just recorded images. Under these ideal conditions, a third of pediatricians misdiagnosed retracted eardrums like Ernie's as infections.

How do real ear infections happen? Sometimes, when children get colds, bacteria and viruses from the throat climb through the gummed-up Eustacian tube and run amok within the ear. The body fights back with pus, and a pediatrician sees an inflamed eardrum bulging under fluid.

In studies, doctors have stuck needles through eardrums to analyze the pus. About a quarter of such children have no live infection -- the body has already won the battle. Most do have bacteria in the pus, however, and antibiotics kill them.

Based on these studies, you'd think that antibiotics would help ear infections get better faster. They generally don't. Three-quarters of ear infections -- including those from bacteria hard to kill in the lab -- get better without antibiotics. Last month, the American Academy of Pediatrics summarized more than 100 studies and concluded that antibiotics have no impact on symptom relief after one, three, and seven days, and no significant effect on ear pain duration or serious complications like meningitis. They did reduce fever by one day.

How about hearing? Fluid in the inner ear can take months to resolve, limiting hearing in the meantime. Since no antibiotic accelerates fluid removal, none restores normal hearing faster. If fluid persists long enough to cause hearing problems, the treatment is ear tubes, not antibiotics. (Another concerning finding from the video study: 50 percent of pediatricians wrongly diagnosed old fluid as an acute infection. This explains how some pediatricians mistakenly can prescribe more and more powerful antibiotics for ear infections that don't seem to respond.)

Antibiotics also have side effects. They induce vomiting or diarrhea in one in six children, and rashes in 2 percent. They've also caused bacteria to become more resistant nationwide.

The academy now suggests that doctors give Tylenol or Motrin right away, but hold off on antibiotics for two to three days for most ear infections. To be on the safe side, antibiotics are still recommended for persistent or severe symptoms, for a clear diagnosis under 2 years old, and for children under 6 months, even if a look in the ears is inconclusive. Though a sea change, this practice is still conservative. The Dutch, for example, avoid initial antibiotics in all children over 6 months.

If antibiotics are chosen, the academy recommends amoxicillin, which costs under $10 per course. But given the 16 million annual prescriptions for ear infections, drug companies also market their expensive antibiotics.

For example, to promote Zithromax, Pfizer donated a live zebra named Max (after the drug's mascot) to the San Francisco Zoo, and pays to have major pediatric journals wrapped in ads. In 2000, Zithromax was the nation's top selling antibiotic, propelled by Pfizer's multibillion-dollar sales budget and 20,000 salespeople.

The academy only recommends more powerful drugs for children with amoxicillin allergies, or when initial treatment with amoxicillin fails. (In studies, less than one in 10 children whose parents think they're allergic really are.) But on its website, Pfizer still promotes Zithromax's dosing convenience over Augmentin, another expensive antibiotic, citing improvement in 75 percent of treated children. They don't mention that's about the same as no antibiotics at all.

What's a parent to do? First, children should get flu vaccines. Because most ear infections start with viruses, the vaccine reduces them by 30 percent in children over 2. The vaccine, Prevnar, may help by another 6 percent. Second, remember that not all ear pain is due to infection. Third, know that antibiotics don't help most ear infections, and don't always expect them, even when you've bundled the kids off to the doctor and forked over the copayment. In surveys, 50 percent of pediatricians think parental pressure makes them overprescribe antibiotics.

Finally, don't let you child hurt unnecessarily. Use Tylenol or Motrin and topical eardrops for pain, since nobody gets extra points for toughing it out. Give the medicine on a schedule, instead of waiting for the crying to start.

Dr. Darshak Sanghavi can be reached at darshak.sanghavi. .

Copyright 2004 The New York Times Company