WEDNESDAY, Aug. 25, 2004 (HealthDayNews) -- An allergic inflammatory disease of the esophagus triggered by immune cells may be on the rise among U.S. children, a new study finds.
The chronic disorder, called eosinophilic esophagitis (EE), is characterized by irritation and inflammation of the esophagus, the tube that carries food from the throat to the stomach. As the esophagus narrows, children with EE suffer discomfort and difficulty when swallowing food, and vomiting is not uncommon.
Rates for the disease appear to be on the rise. The percentage of children affected with EE may now outrank those with better-known gastrointestinal ailments such as Crohn's disease or ulcerative colitis, according to the study.
The findings are published in a research letter in the Aug. 26 issue of the New England Journal of Medicine.
"Our study found a considerable rise in cases, especially in the past few years," said lead researcher Dr. Marc E. Rothenberg, director of allergy and immunology at Cincinnati Children's Hospital Medical Hospital.
His team reviewed data from the hospital's pathology lab database dating back to 1991. The hospital is the single provider of pediatric gastroenterology care for the greater Cincinnati area, so a review of former patients would give the researchers a sense of any local changes in the incidence of EE.
They identified 315 cases of confirmed disease among pediatric patients, "with only 2.8 percent having been identified before 2000," Rothenberg said. Many of the cases were clustered in families, usually among siblings. This could point to "either genetic links or shared environment" as possible factors, he said.
By the end of 2003, more than four of every 10,000 children in the Cincinnati area were estimated to suffer from EE -- a number similar to that of more common chronic gastrointestinal ailments.
"What's new about this report about eosinophilic esophagitis is that it had been a previously under-appreciated syndrome," said Dr. Lanny J. Rosenwasser, professor of medicine and allergy at the National Jewish Medical and Research Center in Denver. "Its prevalence is really exploding now that it's being recognized, especially in the pediatric age group."
Rosenwasser said it's hard to figure out whether the condition is simply being detected more often or whether there has been a sharp increase in new cases, as has been the case with other allergic conditions, such as asthma. "Some of it may be that people haven't been aware of it," he said. "But it may be that allergic diseases in general are increasing in prevalence, too."
The disease isn't confined to children, either. "It's possible that many cases of GERD in adults are [undiagnosed] EE, that's been unexplored as of yet," Rosenwasser said.
EE is characterized by the abnormal proliferation in the esophagus of eosinophils, which are inflammatory immune cells. Because symptoms often mimic those of gastrointestinal esophageal reflux disorder (GERD), EE is often mistaken for pediatric GERD.
"It's probably misdiagnosed very easily," Rosenwasser said. "I don't know how many doctors are aware of it. It's probably not on the radar screen for many primary-care physicians."
In fact, Rothenberg said, "many patients wait for years before a correct diagnosis is made. Once a proper diagnosis is established, children are treated with antacids and proton pump inhibitor drugs (like Prilosec) to help ease gastrointestinal symptoms, and anti-allergy drugs to help fight the underlying cause of the disorder.
Rothenberg stressed that more study needs to be done to see if the sudden rise in EE is occurring elsewhere in the nation. "It could be something specific to this area," he said.
Scientists need to learn much more about the causes of this emerging threat, as well. "We have to find out why these eosinophils are collecting in the esophagus," Rosenwasser said, "to get a better understanding of their basic biology."
More information
For more on EE, visit the Cincinnati Children's Hospital Medical Center.
