A Randomized, Double-Blind, Placebo-Controlled Trial of Fluticasone Propionate for Pediatric Eosinophilic Esophagitis

Flow diagram of study participants.

Percent of patients achieving response. Response (prespecified during study design) was defined as a peak eosinophil count of ≤1 eosinophil/HPF in both the proximal and distal esophagus. Response rates using different definitions of remissions were also calculated to determine if these influenced response rates. These included a higher peak eosinophil count (6 eosinophils/HPF), mean eosinophil count of ≤1 or ≤2, and percent reduction in peak eosinophil count from pretreatment to posttreatment (90% or 95% decrease). *P < .05.

Effect of FP therapy on esophageal eosinophil levels in the (A) proximal and (B) distal esophagus. Response to FP was nearly complete or absent; only 3 patients had intermediate eosinophil levels (between 1 and 24 eosinophils/HPF) after treatment with FP.

Effect of FP therapy on epithelial hyperplasia in the esophagus. On histologic examination, the thickness of the basal layer in relation to the entire epithelium was estimated in well-oriented sections, and epithelial hyperplasia was graded on a 4-point scale: no hyperplasia, basal layer occupying less than one third of the total epithelial thickness, basal layer occupying one third to two thirds of the total epithelial thickness, and basal layer occupying more than two thirds of the total epithelial thickness. Treatment with FP reduced epithelial hyperplasia in the proximal (not shown) and distal esophagus (A), while placebo had no effect. The reduction in epithelial hyperplasia was limited to FP responders (B). These results were confirmed by immunohistochemical analysis with MIB-1 in the (C) proximal and (D) distal esophagus. *P < .05, **P < .01.

Esophageal eosinophil levels by allergy status in the FP group before and after therapy. A and B represent the proximal and distal esophagus, respectively. Allergic patients were defined as those with any positive skin prick test result to food and/or environmental allergens. Only nonallergic patients showed a significant decrease in esophageal eosinophil levels with FP treatment. This effect was more pronounced in the proximal esophagus. *P < .05.

Effect of patient characteristics on response to FP. FP responders were significantly (A) younger, (C) shorter, and (E) lighter in weight than nonresponders. (B) Age, (D) height, and (F) weight significantly correlated with eosinophil levels in the distal esophagus after treatment with FP. *P < .05, **P < .01, ***P < .001.

Immunopathologic effects of FP on the esophagus. Treatment with FP decreased esophageal CD8⁺ T cell counts in both the proximal (not shown) and (A) distal esophagus, but this decrease was limited to FP responders. Treatment with FP also decreased esophageal mast cell counts in both the proximal (not shown) and (B) distal esophagus, but this decrease was limited to FP responders. FP responders had lower posttreatment levels of mast cells than FP nonresponders. *P < .05, **P < .01.