This post will largely be limited to reviewing a single scientific paper, entitled “The Role of Extraesophageal Reflux in Otitis Media in Infants and Children,” by Dr. Robert O’Reilly and the team at DuPont Hospital for Children in Delaware.
This was a significant study, published in 2008 in the journal, Laryngoscope, a premiere journal in the specialty of Otolaryngology. This study included over 500 children (893 ear samples), looking for evidence of a link between reflux and middle ear infections (otitis media).
The result: there IS a link between reflux and ear infections, larger than many expected! Read on for the details, and how to use this information.
How Can We Tell There is Reflux?
For evidence of reflux affecting the ear, Dr. O’Reilly’s group decided to look for evidence of stomach acid (and other stuff) making it all the way to the middle ear. The marker that they measured to indicate the presence of gastric contents was pepsin. Pepsin is a gastric enzyme, present only in the stomach.
They reasoned that the only way for pepsin to get to the middle ear space in a child would be for that child to reflux it up.
Take a look at the figure on the right: reflux up the esophagus doesn’t need to go very far before it gets to the openings of the Eustachian tubes. Those are the small tubes that go from the back of the throat / nose area (“nasopharynx”) to behind the ear drum. They function to equalize the pressure between the middle ear space and surrounding air pressure.
How does that happen?
Well, reflux of stomach contents goes up the esophagus, into the nasopharynx (back of the throat), and up the Eustachian tubes to the ears. Regurgitation going all the way up into a baby’s ears. Yuck.
Others have thought of using this marker before, and there have been small, ”pilot” studies suggesting that pepsin can be found in the middle ears of children who have reflux.
There have been 2 main challenges to getting useful data in the past:
- The first has been having appropriate “controls” – that is, children without any significant history of ear infections, who wouldn’t mind if we sample their middle ears for the presence of pepsin. That is, normal children are not standing in line to be put under general anesthetic so that we can make a small incision in their ear drum to see whether there is any pepsin in there.Dr. O’Reilly’s group found a great solution – a group of children with no history of ear infections who would be undergoing some un-related ear surgery: kids who were getting electronic ears (cochlear implants) placed. This group of 64 children comprised their “control” or normal group.
- The second challenge has been obtaining a large enough group of samples (from enough children) that the results have real statistical meaning.Dr. O’Reilly’s group has been the first to collect such a large sample, providing for the first time such statistically significant results. After all, they had 509 children with chronic ear infections, and 64 children without chronic ear infections.
Here is what they found:
- Pepsin was present in the ear of 20% of the children with recurrent and chronic ear infections.
- Pepsin was present in the ears of only 1.4% of the control children.
- Children younger than 1 year had a higher rate of purulent (infected with pus) ears and also pepsin in the middle ear.
- Children with pepsin in their ears were more likely to have fluid in their ears than those children without pepsin.
- Most interestingly, there was NO correlation between the presence of pepsin and a reported history of reflux, allergies, or asthma.
The differences described were all “statistically significant,” with a p-value < 0.05.
The authors of the study concluded that pepsin in the middle ear was an “independent risk factor” for otitis media. In other words, reflux is linked to ear infections.
They also note that clinical history of reflux – that is, the parents’ or physicians’ ability to diagnose reflux in infants – did not have any bearing on whether these children were found to have pepsin (from reflux) in their middle ears. This just tells me that we stink at diagnosing reflux in little tykes based simply on clinical history, or asking the parents.
What to Do With This Information?
What we can take away from this study is that we (pediatric boogor docs) should consider treating reflux in our patients with recurrent and chronic ear infections.
If your little boogor head has chronic ear infections and your doc is recommending ear tubes, you might ask about the possible role of reflux and see what they say. They may already be hip to these results. You might save your child a surgery.