KEYSTONE, COLO. — Use of an elemental diet in patients with eosinophilic esophagitis is extremely effective—albeit draconian, disruptive, and seldom necessary, Dr. David M. Fleischer said at a meeting on allergy and respiratory disease sponsored by the National Jewish Medical and Research Center.
“We don't want to eliminate all foods, because it's hard on the patient. They're more likely to cheat on that diet,” according to Dr. Fleischer, a pediatric allergist at the center.
“We don't usually put patients on an elemental diet, because we want them to be able to eat other foods. So we spend the time to find out what foods they can't eat and take them out of the diet,” he said.
He and his colleagues rely upon skin prick testing and radioallergosorbent tests for meats, grains, eggs, and a limited number of the other major food antigens in constructing individualized elimination diets. Patch testing is utilized at some other centers.
The reliability of all of these tests is questionable; results need to be correlated with clinical findings.
“It's more of an art than a science. It can be complicated to figure out what the offending foods are,” he conceded.
That being said, modern elemental formula liquid diets don't taste as bad as they used to, and they are nutritionally fairly complete, needing only supplemental calcium and a few other nutrients for long-term use, Dr. Fleischer continued.
Multiple studies demonstrate that the use of an elemental diet in children with eosinophilic esophagitis is effective in 92%–98% of cases. Symptoms resolve in 7–10 days.
The esophageal eosinophilia drops from the 15 or more cells per high-power field (HPF) required for the diagnosis to zero cells or close to it in 4–5 weeks.
Elimination diets guided by allergy testing are often nearly as effective.
A low-cost, no-hassle alternative elimination diet has been described by pediatric gastroenterologist Dr. Amir Kagalwalla and coworkers at Northwestern University, Chicago. They dispensed with allergy testing and instead simply removed six of the most common allergenic foods from the diets of 35 children with eosinophilic esophagitis. The excluded foods were milk, soy, wheat, egg, peanut, and seafood.
Upon repeat esophageal biopsy at least 6 weeks later, esophageal inflammation was significantly improved to 10 or fewer eosinophils/HPF in 26 of the 35 children (74%). From a mean baseline of 80 cells, the posttreatment average fell to 13.6 eosinophils/HPF. The histologic response was associated with clinical improvement (Clin. Gastroenterol. Hepatol. 2006;4:1097–102).
But the on-treatment eosinophil count achieved with this approach remained well above normal.
And that makes Dr. Fleischer uneasy. “We don't know what it means long term. Will it prevent esophageal strictures?” he wondered.
As part of the same retrospective observational study, Dr. Kagalwalla and colleagues also assigned 25 children to a liquid elemental diet. Esophageal eosinophilia dropped from a mean baseline of 59 cells/HPF to 3.7 cells/HPF. Twenty-two of the 25 treated patients (88%) experienced a significant reduction in esophageal inflammation as defined by a reduction to not more than 10 eosinophils/HPF.
Most patients with eosinophilic esophagitis also respond to antiallergy medication.
For example, having patients swallow inhaled corticosteroids so the topical medication coats the esophagus quells their esophageal inflammation. When the regimen is stopped, however, the eosinophilic esophagitis returns.