Esophageal Subepithelial Fibrosis in Children With Eosinophilic Esophagitis

OBJECTIVES: Esophageal subepithelial fibrosis has been reported in adults with eosinophilic esophagitis (EE). Our goal was to determine the prevalence of esophageal fibrosis in children with EE, to determine whether it is specific for EE, and to correlate it with clinical and pathological features. PATIENTS AND METHODS: Twenty-one children with EE, 7 with eosinophilic gastroenteritis, 6 with gastroesophageal reflux disease, and 17 control children were studied. Distal esophageal biopsy specimens containing lamina propria were evaluated for extent of subepithelial collagen deposition by use of trichrome staining. Fibrosis was defined as abnormally increased collagen deposition, determined after the establishment of normal patterns on sections of esophagus from pediatric autopsies. Maximum numbers of intraepithelial and lamina propria eosinophils per high-power field by hematoxylin and eosin staining and mast cells per high-power field by immunohistochemical staining for tryptase were determined. Eosinophil and mast cell degranulation in epithelium and lamina propria was determined by use of immunohistochemical staining for major basic protein and tryptase, respectively. The patients' records were reviewed. RESULTS: Esophageal subepithelial fibrosis was present in 12 (57%) patients with EE, 1 with eosinophilic gastroenteritis, 0 with gastroesophageal reflux disease, and 1 control patient. Forty-two percent of those with fibrosis had dysphagia, 80% of whom had food impactions; these symptoms were present only in patients with fibrosis. Within the EE group, fibrosis was not associated with duration of symptoms or with increasing numbers of infiltrating eosinophils/mast cells, but it was associated with eosinophil degranulation. CONCLUSIONS: Esophageal subepithelial fibrosis is prevalent in EE and is specific for the disease in children. It is associated with dysphagia, and it may explain and predict future esophageal dysmotility. Fibrosis is related to the extent of esophageal eosinophil activation, as evidenced by eosinophil degranulation.