Friday, June 03, 2011
The first study of its kind to examine the long-term natural history of an emerging new disease, eosinophilic esophagitis, has identified factors associated with complications and reveals that children with the disorder have persistent disease into adulthood.
The study, published online June 3 in the Journal of Allergy and Clinical Immunology, was conducted by researchers at Cincinnati Children’s Hospital Medical Center. They studied hundreds of people diagnosed with high counts of esophageal eosinophils before eosinophilic esophagitis was known to be a separate disease. Eosinophils are white blood cells typically involved in allergy and parasitic infections.
“This important set of findings suggests that disease severity is greater among patients with allergies,” says Marc Rothenberg, MD, PhD, director of the Division of Allergy and Immunology and the Cincinnati Center for Eosinophilic Disorders, and senior author of the study. The study’s lead authors were James Franciosi, MD, and Charles DeBrosse, MD.
“Taken one step further, these data support the need for allergy testing among patients with eosinophilic esophagitis, as identifying patients susceptible to allergic reactions will not only assist in dietary management but will help identify those at greatest risk for persistent disease,” Franciosi says.
The study concludes that esophageal eosinophilia is associated with reduced quality of life and persistent symptoms as much as 15 years after initial diagnosis. In addition, elevated eosinophil counts in combination with other allergies during childhood increase the risk of swallowing difficulties in adulthood.
Eosinophilic esophagitis is a swelling of the esophagus that results in many symptoms, including difficulty swallowing (dysphagia) as well as structural changes and high eosinophil counts (eosinophilia). Sometimes this inflammatory reaction is so severe that managing symptoms requires eliminating solid food and providing nutrition via special liquid formula.
Eosinophilic esophagitis was established as a separate disease in 2007. Until recently, patients suffering from this disease were often misdiagnosed as having gastroesophageal reflux disease (GERD) or chronic esophagitis. Researchers now estimate that about one in every 1,000 people in the U.S. suffer from eosinophilic esophagitis. Cincinnati Children’s encounters about 30 cases each week.
“This emerging disorder is attracting increasing interest among allergists, gastroenterologists, pathologists, and primary care physicians,” Rothenberg says. “However, identifying how best to manage this condition has been hindered by a lack of data regarding long-term outcomes.”
Researchers at Cincinnati Children’s embarked upon a novel project to examine the natural history of eosinophilic esophagitis during the transition from childhood into adulthood.
The project involved reviewing 3,817 pediatric esophageal biopsy specimens from 1982-1999. This revealed more than 660 patients with retrospectively identified eosinophilic esophagitis and chronic esophagitis. This group and an age-matched control group were asked to complete health-related outcome questionnaires. The study collected 209 completed questionnaires.
The surveys show that quality of life was significantly decreased among patients with eosinophil-associated esophagitis compared to the control group. In fact, 73 percent of patients with eosinophilic esophagitis suffered symptoms into adulthood. Difficulty with swallowing was reported among 49 percent of patients with esophageal eosinophilia compared to 6 percent for the control group. Elevated eosinophil counts during childhood were predictive of this condition in adulthood.
Food impaction in the esophagus was reported among 40 percent of patients with esophageal eosinophilia and 14 percent of patients with chronic esophagitis compared to 3 percent of the control group.
Higher rates of swallowing difficulty occurred if patients also had a food allergy, allergic rhinitis or asthma. Food impaction was more common among patients with reported food allergy.
These findings support more comprehensive allergy testing for patients with esophageal eosinophilia to help guide symptom management. In addition, the evidence of long-lasting symptoms for untreated patients substantiates more aggressive treatment approaches for children.
“Most patients with eosinophilic esophagitis are not currently diagnosed,” Rothenberg says. “If you have long-term upper GI symptoms and especially if you are an allergic person, you should have your physician consider this disease.”
The study was supported by the Campaign Urging Research for Eosinophilic Disease (CURED), the Food Allergy Initiative (FAI), the National Institutes of Health (NIH), the Buckeye Foundation, and The International Group of Eosinophilic Researchers (TIGER).