Alimentary Pharmacology and Therapeutics
INTRODUCTIONEosinophilic oesophagitis (EoO) is a chronic inflammatory disorder of the oesophagus characterised by the proton pump inhibitor-refractory accumulation of eosinophils in the oesophageal epithelium [>15 intraepithelial eosinophils ⁄ high powered field (eos ⁄ hpf)] in combination with a range of symptoms including dysphagia, food impaction, chest pain, abdominal pain and vomiting. [1][2][3] The clinical manifestations of EoO vary with age. Nearly all adults complain of solid food dysphagia with many being 'slow eaters' who meticulously chew their food. More than 50% give a history of food impaction.The endoscopic features of EoO suggest a chronic disease with inflammatory features of furrows, microabscesses and plaques seen predominantly in paediatric patients and oesophageal remodelling characterised by the narrow calibre oesophagus, strictures and ring formation more commonly seen in adult EoO patients. Most likely these changes are progressive in nature, but this is a speculation yet to be defined with serial studies from childhood to adulthood. The treatments for these early inflammatory changes are anti-inflammatory medications (swallowed fluticasone, budesonide, prednisone) or restrictive and elemental diets. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] On the other hand, adult EoO patients typically show less active inflammation and more fibrotic changes due to collagen deposition in the epithelium and submucosa. Straumann et al. 19 performed a randomised, double-blind placebocontrolled trial with 36 adults and adolescents treating them with swallowed budesonide for 15 days. On followup oesophagogastroduodenoscopy, the oesophageal eosinophilia and furrowing drastically improved, but the corrugated rings persisted. Oesophageal dilation is often necessary to correct this fixed stenosis, which relieves the solid food dysphagia and alleviates the fear of food impaction, improving quality of life. Potential side effects of too aggressive dilation are concerning, but the longterm relief seems to outweigh these complications. This systematic narrative review will discuss the pathophysiology producing remodelling and strictures, review the available case series, discuss the technique of oesophageal dilation in the management of adult EoO patients and its potential complications.
PathophysiologyOesophageal remodelling in EoO patients is a major factor contributing to the clinical complaint of solid food dysphagia. The process begins with an influx of inflammatory cells, especially eosinophils into the mucosa of the oesophagus. Over time, numerous microscopic changes occur including basal cell hyperplasia, elongated rete pegs, smooth muscle hypertrophy ⁄ hyperplasia, and lamina propria ⁄ subepithelial fibrosis. 20 These histopathologic changes are evident on endoscopy as strictures, narrowing and rings and on endoscopic ultrasound as diffuse thickening of all layers of the oesophagus. 21 Most of what we know about the remodelling process in EoO is based u...