Ear Infections Are Top Reason for Childhood MD Visits

Middle ear infections (otitis media) account for the majority of children's doctor visits in the United States, and Joseph E. Kerschner, MD, FACS, FAAP said most children will have at least one ear infection by the age of two or three. The cost of managing ear infections in the US is $6 million annually. "It's very common, and it's expensive, and it's something that does warrant further study," Dr. Kerschner said.

While some children may get few, others are plagued by chronic ear infections. "There's a risk factor profile for children," said Dr. Kerschner, Medical College of Wisconsin Professor of Otolaryngology and Communication Sciences, Academic Vice Chairman and chief of the Division of Pediatric Otolaryngology. Dr. Kerschner sees patients and performs surgery at Children's Hospital of Wisconsin's main campus and also operates at the SurgiCenter of Greater Milwaukee.

Chronic Ear Infections: Risk Factors and Diagnosis
"The biggest factor that is associated with kids getting chronic or recurring ear infections is being in day care," Dr. Kerschner said. "It's simply that kids share lots of germs and viruses when they're in a day care environment and, when they're really young especially and their immune systems aren't fully developed or are still developing, they are at a greater risk of getting ear infections."

Family history, tobacco exposure and lower socioeconomic status are also identified as risk factors while breastfeeding has a protective effect. "Breastfeeding has been shown to have a protective effect, so if a child is breastfed, they are less likely to get ear infections," Dr. Kerschner said.

Recognizing ear infections, especially in very young children, can sometimes be difficult. "The presenting signs of otitis media are rapid or acute onset of difficulty which includes fever, pain and irritability," Dr. Kerschner said. "Once in a while a child will have actual ear drainage you can see. Barring that, a child who has a fever, pain or is irritable then is seen by their physician." These presenting symptoms are relatively nonspecific and the diagnosis requires the physician being able to see the ear drum and assessing if it is inflamed and if there is infection and fluid behind the ear drum.

Ear Infection Treatments Vary with Cause and Frequency
Middle ear infections are primarily bacterial or viral. "Viral infections generally are self-limited; meaning they get better on their own over time. Bacterial infections sometimes can get better on their own but oftentimes need some other kind of treatment," Dr. Kerschner said. "A lot of times you can see bacterial and viral infections in the middle ear at the same time." According to Dr. Kerschner, there are three main bacteria that cause ear infections - Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis. "Those are the three bacteria we focus most of our energy on."

Treatment depends on the cause of the ear infection - either viral or bacterial. "If you think it's a viral infection, obviously antibiotics won't help. The problem is, you can't really tell the difference between a bacterial and viral infection just by looking at the ear, so that's why some people have advocated waiting a day or two before you treat with antibiotics," Dr. Kerschner said. "There is a school of thought that if the infection is not severe, especially in older children, you can withhold antibiotics for a day or two and see if their symptoms start to get better on their own." That approach, however, can be difficult and depends on good communication between parents and physician and close follow-up of the patient.

For those with chronic ear infections, one option is a surgery with myringotomy and ventilation tube placement which involves having small tubes placed in the ear drum. Dr. Kerschner said ear tubes are considered in children with three to four infections in a six-month period or four to five infections in a 12-month period.

"With the increasing number of bacteria that are resistant to antibiotics, some experts feel that maybe ear tubes should be used more frequently in kids who are getting recurrent infections," Dr. Kerschner said. "If you look internationally, countries such as The Netherlands use the fewest antibiotics because of all the things we've talked about - antibiotic resistance, difficulties with antibiotics and the fact that some ear infections get better on their own - have the highest rate of ear tube insertions. It's not that they need more ear tubes, it's just that there's an understanding that as time has gone forward, antibiotics are less effective at treating ear infections."

Chronic fluid behind the eardrum after ear infections can have long-term effects on a child's hearing, speech development, and language skills. "It can cause permanent hearing loss," said Dr. Kerschner. "But more typically it causes a temporary hearing loss that stays as long as the fluid remains. Decisions on placing ventilation tubes in children with chronic fluid depend on many factors but should generally be considered after the fluid has been present for 4 to 6 months. It really depends on the child, but this fluid is especially problematic for children who have other health issues. So any other developmental delay, any speech delay, children with cleft palate or Downs syndrome should be referred to an otolaryngologist sooner rather than later."

Ongoing Research Investigates Ear Infection Causes and Treatments
Dr. Kerschner has funding from the National Institutes of Health to investigate the cause of and potential new treatments for ear infections. "Our grant from the National Institutes of Health is looking at two or three different things, but it's mostly trying to understand what's happening to children who get lots of ear infections on a molecular level and on a cellular level, so we're doing lots of experiments through this grant to look at what happens to the ear cells themselves during periods of inflammation. We're looking at specific inflammatory mediators to look at how those impact the ear lining or epithelium itself."

The study is also investigating mucin genes, a substance that helps protect the ear as well as biofilms. "Biofilms are a new concept for ear infections, just this past year we published an article in JAMA (The Journal of the American Medical Association) where we talk about the fact that it appears that children's ear infections are associated with biofilms. These biofilms are a different way that the bacteria live and makes them fairly hard to treat with antibiotics. So especially in children that seem to have the chronic forms of ear infections or who have persisting of their middle ear fluid, it appears that the biofilm may be a contributing or the main causative factor in that," said Dr. Kerschner.

Other solutions for ear infections are also being studied, Dr. Kerschner said, including vaccines. "The pneumococcal vaccine has made a difference. It has helped to reduce the incidence of ear infections to some degree, and it also targets the most resistant forms of pneumococcus (Streptococcus pneumoniae)."

Melissa Rigney Baxter
HealthLink Contributing Writer

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.