Clinical meaning
An esophageal stricture is a narrowing of the esophageal lumen caused by fibrotic scar tissue formation within the esophageal wall, resulting in progressive difficulty swallowing (dysphagia). The most common cause is chronic gastroesophageal reflux disease (GERD), which accounts for approximately 70-80% of benign esophageal strictures. In GERD, the lower esophageal sphincter (LES) fails to maintain adequate resting tone, allowing retrograde flow of gastric acid, pepsin, and bile salts into the distal esophagus. Under normal physiological conditions, the esophageal mucosa is lined by non-keratinized stratified squamous epithelium, which is not designed to withstand repeated exposure to the acidic gastric contents (pH 1.0-2.0). Chronic acid exposure damages the epithelial barrier through direct hydrogen ion penetration, activation of pepsin at low pH (which degrades epithelial proteins), and bile salt-mediated disruption of cell membrane integrity. The initial injury produces reflux esophagitis, characterized by superficial mucosal erosions, inflammation, and edema. When acid exposure is severe, prolonged, or repetitive over months to years, the inflammatory process extends deeper into the submucosa and muscularis propria. The tissue repair process involves activation of fibroblasts and myofibroblasts within the esophageal wall, which deposit excessive collagen and extracellular matrix proteins (primarily collagen types I and III). Transforming growth factor-beta (TGF-beta) is the key cytokine driving this fibrogenic response. Over time, the accumulating fibrotic tissue contracts and narrows the esophageal lumen, creating a stricture. Peptic strictures typically develop at the squamocolumnar junction in the distal esophagus where acid exposure is greatest. Other causes of esophageal strictures include eosinophilic esophagitis (proximal and mid-esophageal rings and strictures from eosinophilic inflammation), caustic ingestion (alkali or acid burns producing extensive fibrosis), radiation therapy to the chest or neck (radiation-induced fibrosis), prolonged nasogastric tube placement, post-surgical anastomotic strictures, and pill esophagitis from medications lodging in the esophagus (bisphosphonates, doxycycline, potassium chloride, NSAIDs). Malignant strictures from esophageal carcinoma (squamous cell carcinoma or adenocarcinoma) must always be excluded in any patient presenting with progressive dysphagia, particularly those over 50 years with alarm symptoms (weight loss, anemia, odynophagia). The practical nurse must understand that dysphagia is a progressive symptom: patients initially have difficulty swallowing solids (because the narrowed lumen can still accommodate liquids), then progress to difficulty with both solids and liquids as the stricture tightens. The esophageal lumen must be narrowed to approximately 13 mm or less before dysphagia for solids typically occurs, and to less than 9 mm before dysphagia for liquids develops.